#
92383111 |
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15-Feb-2024 |
Roberto Sassu <roberto.sassu@huawei.com> |
evm: Move to LSM infrastructure As for IMA, move hardcoded EVM function calls from various places in the kernel to the LSM infrastructure, by introducing a new LSM named 'evm' (last and always enabled like 'ima'). The order in the Makefile ensures that 'evm' hooks are executed after 'ima' ones. Make EVM functions as static (except for evm_inode_init_security(), which is exported), and register them as hook implementations in init_evm_lsm(). Also move the inline functions evm_inode_remove_acl(), evm_inode_post_remove_acl(), and evm_inode_post_set_acl() from the public evm.h header to evm_main.c. Unlike before (see commit to move IMA to the LSM infrastructure), evm_inode_post_setattr(), evm_inode_post_set_acl(), evm_inode_post_remove_acl(), and evm_inode_post_removexattr() are not executed for private inodes. Finally, add the LSM_ID_EVM case in lsm_list_modules_test.c Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Reviewed-by: Casey Schaufler <casey@schaufler-ca.com> Acked-by: Christian Brauner <brauner@kernel.org> Reviewed-by: Stefan Berger <stefanb@linux.ibm.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Acked-by: Mimi Zohar <zohar@linux.ibm.com> Signed-off-by: Paul Moore <paul@paul-moore.com>
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#
2d705d80 |
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15-Feb-2024 |
Roberto Sassu <roberto.sassu@huawei.com> |
security: Introduce inode_post_remove_acl hook In preparation for moving IMA and EVM to the LSM infrastructure, introduce the inode_post_remove_acl hook. At inode_remove_acl hook, EVM verifies the file's existing HMAC value. At inode_post_remove_acl, EVM re-calculates the file's HMAC with the passed POSIX ACL removed and other file metadata. Other LSMs could similarly take some action after successful POSIX ACL removal. The new hook cannot return an error and cannot cause the operation to be reverted. Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Reviewed-by: Stefan Berger <stefanb@linux.ibm.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Acked-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Paul Moore <paul@paul-moore.com>
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#
8b9d0b82 |
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15-Feb-2024 |
Roberto Sassu <roberto.sassu@huawei.com> |
security: Introduce inode_post_set_acl hook In preparation for moving IMA and EVM to the LSM infrastructure, introduce the inode_post_set_acl hook. At inode_set_acl hook, EVM verifies the file's existing HMAC value. At inode_post_set_acl, EVM re-calculates the file's HMAC based on the modified POSIX ACL and other file metadata. Other LSMs could similarly take some action after successful POSIX ACL change. The new hook cannot return an error and cannot cause the operation to be reverted. Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Reviewed-by: Stefan Berger <stefanb@linux.ibm.com> Acked-by: Casey Schaufler <casey@schaufler-ca.com> Reviewed-by: Mimi Zohar <zohar@linux.ibm.com> Acked-by: Christian Brauner <brauner@kernel.org> Signed-off-by: Paul Moore <paul@paul-moore.com>
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#
a69ce85e |
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31-Jan-2024 |
Jeff Layton <jlayton@kernel.org> |
filelock: split common fields into struct file_lock_core In a future patch, we're going to split file leases into their own structure. Since a lot of the underlying machinery uses the same fields move those into a new file_lock_core, and embed that inside struct file_lock. For now, add some macros to ensure that we can continue to build while the conversion is in progress. Signed-off-by: Jeff Layton <jlayton@kernel.org> Link: https://lore.kernel.org/r/20240131-flsplit-v3-17-c6129007ee8d@kernel.org Reviewed-by: NeilBrown <neilb@suse.de> Signed-off-by: Christian Brauner <brauner@kernel.org>
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#
376870aa |
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15-Dec-2023 |
Alexander Mikhalitsyn <alexander@mihalicyn.com> |
fs: fix doc comment typo fs tree wide Do the replacement: s/simply passs @nop_mnt_idmap/simply pass @nop_mnt_idmap/ in the fs/ tree. Found by chance while working on support for idmapped mounts in fuse. Cc: Jan Kara <jack@suse.cz> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Christian Brauner <brauner@kernel.org> Cc: <linux-fsdevel@vger.kernel.org> Cc: <linux-kernel@vger.kernel.org> Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com> Link: https://lore.kernel.org/r/20231215130927.136917-1-aleksandr.mikhalitsyn@canonical.com Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
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#
2276e5ba |
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05-Jul-2023 |
Jeff Layton <jlayton@kernel.org> |
fs: convert to ctime accessor functions In later patches, we're going to change how the inode's ctime field is used. Switch to using accessor functions instead of raw accesses of inode->i_ctime. Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Jeff Layton <jlayton@kernel.org> Message-Id: <20230705190309.579783-23-jlayton@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
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#
e499214c |
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01-Feb-2023 |
Christian Brauner <brauner@kernel.org> |
acl: don't depend on IOP_XATTR All codepaths that don't want to implement POSIX ACLs should simply not implement the associated inode operations instead of relying on IOP_XATTR. That's the case for all filesystems today. For vfs_listxattr() all filesystems that explicitly turn of xattrs for a given inode all set inode->i_op to a dedicated set of inode operations that doesn't implement ->listxattr(). We can remove the dependency of vfs_listxattr() on IOP_XATTR. Removing this dependency will allow us to decouple POSIX ACLs from IOP_XATTR and they can still be listed even if no other xattr handlers are implemented. Otherwise we would have to implement elaborate schemes to raise IOP_XATTR even if sb->s_xattr is set to NULL. Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
d549b741 |
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01-Feb-2023 |
Christian Brauner <brauner@kernel.org> |
fs: rename generic posix acl handlers Reflect in their naming and document that they are kept around for legacy reasons and shouldn't be used anymore by new code. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
f2620f16 |
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01-Feb-2023 |
Christian Brauner <brauner@kernel.org> |
xattr: simplify listxattr helpers The generic_listxattr() and simple_xattr_list() helpers list xattrs and contain duplicated code. Add two helpers that both generic_listxattr() and simple_xattr_list() can use. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
4d7ca409 |
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12-Jan-2023 |
Christian Brauner <brauner@kernel.org> |
fs: port vfs{g,u}id helpers to mnt_idmap Convert to struct mnt_idmap. Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conversion to struct mnt_idmap. Currently we still pass around the plain namespace that was attached to a mount. This is in general pretty convenient but it makes it easy to conflate namespaces that are relevant on the filesystem with namespaces that are relevent on the mount level. Especially for non-vfs developers without detailed knowledge in this area this can be a potential source for bugs. Once the conversion to struct mnt_idmap is done all helpers down to the really low-level helpers will take a struct mnt_idmap argument instead of two namespace arguments. This way it becomes impossible to conflate the two eliminating the possibility of any bugs. All of the vfs and all filesystems only operate on struct mnt_idmap. Acked-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
e67fe633 |
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12-Jan-2023 |
Christian Brauner <brauner@kernel.org> |
fs: port i_{g,u}id_into_vfs{g,u}id() to mnt_idmap Convert to struct mnt_idmap. Remove legacy file_mnt_user_ns() and mnt_user_ns(). Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conversion to struct mnt_idmap. Currently we still pass around the plain namespace that was attached to a mount. This is in general pretty convenient but it makes it easy to conflate namespaces that are relevant on the filesystem with namespaces that are relevent on the mount level. Especially for non-vfs developers without detailed knowledge in this area this can be a potential source for bugs. Once the conversion to struct mnt_idmap is done all helpers down to the really low-level helpers will take a struct mnt_idmap argument instead of two namespace arguments. This way it becomes impossible to conflate the two eliminating the possibility of any bugs. All of the vfs and all filesystems only operate on struct mnt_idmap. Acked-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
9452e93e |
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12-Jan-2023 |
Christian Brauner <brauner@kernel.org> |
fs: port privilege checking helpers to mnt_idmap Convert to struct mnt_idmap. Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conversion to struct mnt_idmap. Currently we still pass around the plain namespace that was attached to a mount. This is in general pretty convenient but it makes it easy to conflate namespaces that are relevant on the filesystem with namespaces that are relevent on the mount level. Especially for non-vfs developers without detailed knowledge in this area this can be a potential source for bugs. Once the conversion to struct mnt_idmap is done all helpers down to the really low-level helpers will take a struct mnt_idmap argument instead of two namespace arguments. This way it becomes impossible to conflate the two eliminating the possibility of any bugs. All of the vfs and all filesystems only operate on struct mnt_idmap. Acked-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
01beba79 |
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12-Jan-2023 |
Christian Brauner <brauner@kernel.org> |
fs: port inode_owner_or_capable() to mnt_idmap Convert to struct mnt_idmap. Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conversion to struct mnt_idmap. Currently we still pass around the plain namespace that was attached to a mount. This is in general pretty convenient but it makes it easy to conflate namespaces that are relevant on the filesystem with namespaces that are relevent on the mount level. Especially for non-vfs developers without detailed knowledge in this area this can be a potential source for bugs. Once the conversion to struct mnt_idmap is done all helpers down to the really low-level helpers will take a struct mnt_idmap argument instead of two namespace arguments. This way it becomes impossible to conflate the two eliminating the possibility of any bugs. All of the vfs and all filesystems only operate on struct mnt_idmap. Acked-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
700b7940 |
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12-Jan-2023 |
Christian Brauner <brauner@kernel.org> |
fs: port acl to mnt_idmap Convert to struct mnt_idmap. Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conversion to struct mnt_idmap. Currently we still pass around the plain namespace that was attached to a mount. This is in general pretty convenient but it makes it easy to conflate namespaces that are relevant on the filesystem with namespaces that are relevent on the mount level. Especially for non-vfs developers without detailed knowledge in this area this can be a potential source for bugs. Once the conversion to struct mnt_idmap is done all helpers down to the really low-level helpers will take a struct mnt_idmap argument instead of two namespace arguments. This way it becomes impossible to conflate the two eliminating the possibility of any bugs. All of the vfs and all filesystems only operate on struct mnt_idmap. Acked-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
4609e1f1 |
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12-Jan-2023 |
Christian Brauner <brauner@kernel.org> |
fs: port ->permission() to pass mnt_idmap Convert to struct mnt_idmap. Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conversion to struct mnt_idmap. Currently we still pass around the plain namespace that was attached to a mount. This is in general pretty convenient but it makes it easy to conflate namespaces that are relevant on the filesystem with namespaces that are relevent on the mount level. Especially for non-vfs developers without detailed knowledge in this area this can be a potential source for bugs. Once the conversion to struct mnt_idmap is done all helpers down to the really low-level helpers will take a struct mnt_idmap argument instead of two namespace arguments. This way it becomes impossible to conflate the two eliminating the possibility of any bugs. All of the vfs and all filesystems only operate on struct mnt_idmap. Acked-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
13e83a49 |
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12-Jan-2023 |
Christian Brauner <brauner@kernel.org> |
fs: port ->set_acl() to pass mnt_idmap Convert to struct mnt_idmap. Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conversion to struct mnt_idmap. Currently we still pass around the plain namespace that was attached to a mount. This is in general pretty convenient but it makes it easy to conflate namespaces that are relevant on the filesystem with namespaces that are relevent on the mount level. Especially for non-vfs developers without detailed knowledge in this area this can be a potential source for bugs. Once the conversion to struct mnt_idmap is done all helpers down to the really low-level helpers will take a struct mnt_idmap argument instead of two namespace arguments. This way it becomes impossible to conflate the two eliminating the possibility of any bugs. All of the vfs and all filesystems only operate on struct mnt_idmap. Acked-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
77435322 |
|
12-Jan-2023 |
Christian Brauner <brauner@kernel.org> |
fs: port ->get_acl() to pass mnt_idmap Convert to struct mnt_idmap. Last cycle we merged the necessary infrastructure in 256c8aed2b42 ("fs: introduce dedicated idmap type for mounts"). This is just the conversion to struct mnt_idmap. Currently we still pass around the plain namespace that was attached to a mount. This is in general pretty convenient but it makes it easy to conflate namespaces that are relevant on the filesystem with namespaces that are relevent on the mount level. Especially for non-vfs developers without detailed knowledge in this area this can be a potential source for bugs. Once the conversion to struct mnt_idmap is done all helpers down to the really low-level helpers will take a struct mnt_idmap argument instead of two namespace arguments. This way it becomes impossible to conflate the two eliminating the possibility of any bugs. All of the vfs and all filesystems only operate on struct mnt_idmap. Acked-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
5970e15d |
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20-Nov-2022 |
Jeff Layton <jlayton@kernel.org> |
filelock: move file locking definitions to separate header file The file locking definitions have lived in fs.h since the dawn of time, but they are only used by a small subset of the source files that include it. Move the file locking definitions to a new header file, and add the appropriate #include directives to the source files that need them. By doing this we trim down fs.h a bit and limit the amount of rebuilding that has to be done when we make changes to the file locking APIs. Reviewed-by: Xiubo Li <xiubli@redhat.com> Reviewed-by: Christian Brauner (Microsoft) <brauner@kernel.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: David Howells <dhowells@redhat.com> Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Acked-by: Chuck Lever <chuck.lever@oracle.com> Acked-by: Joseph Qi <joseph.qi@linux.alibaba.com> Acked-by: Steve French <stfrench@microsoft.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Acked-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Jeff Layton <jlayton@kernel.org>
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#
4e1da8fe |
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21-Dec-2022 |
Uros Bizjak <ubizjak@gmail.com> |
posix_acl: Use try_cmpxchg in get_acl Use try_cmpxchg instead of cmpxchg (*ptr, old, new) == old in get_acl. x86 CMPXCHG instruction returns success in ZF flag, so this change saves a compare after cmpxchg (and related move instruction in front of cmpxchg). No functional change intended. Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
d6fdf29f |
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01-Dec-2022 |
Uros Bizjak <ubizjak@gmail.com> |
posix_acl: Fix the type of sentinel in get_acl The type should be struct posix_acl * instead of void *. Cc: Christian Brauner <brauner@kernel.org> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
5a6f52d2 |
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28-Oct-2022 |
Christian Brauner <brauner@kernel.org> |
acl: conver higher-level helpers to rely on mnt_idmap Convert an initial portion to rely on struct mnt_idmap by converting the high level xattr helpers. Reviewed-by: Seth Forshee (DigitalOcean) <sforshee@kernel.org> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
a351b1f4 |
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28-Oct-2022 |
Christian Brauner <brauner@kernel.org> |
acl: make vfs_posix_acl_to_xattr() static After reworking posix acls this helper isn't used anywhere outside the core posix acl paths. Make it static. Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
0a26bde2 |
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22-Sep-2022 |
Christian Brauner <brauner@kernel.org> |
acl: remove a slew of now unused helpers Now that the posix acl api is active we can remove all the hacky helpers we had to keep around for all these years and also remove the set and get posix acl xattr handler methods as they aren't needed anymore. Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
318e6685 |
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22-Sep-2022 |
Christian Brauner <brauner@kernel.org> |
xattr: use posix acl api In previous patches we built a new posix api solely around get and set inode operations. Now that we have all the pieces in place we can switch the system calls and the vfs over to only rely on this api when interacting with posix acls. This finally removes all type unsafety and type conversion issues explained in detail in [1] that we aim to get rid of. With the new posix acl api we immediately translate into an appropriate kernel internal struct posix_acl format both when getting and setting posix acls. This is a stark contrast to before were we hacked unsafe raw values into the uapi struct that was stored in a void pointer relying and having filesystems and security modules hack around in the uapi struct as well. Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1] Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
aeb7f005 |
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22-Sep-2022 |
Christian Brauner <brauner@kernel.org> |
acl: add vfs_remove_acl() In previous patches we implemented get and set inode operations for all non-stacking filesystems that support posix acls but didn't yet implement get and/or set acl inode operations. This specifically affected cifs and 9p. Now we can build a posix acl api based solely on get and set inode operations. We add a new vfs_remove_acl() api that can be used to set posix acls. This finally removes all type unsafety and type conversion issues explained in detail in [1] that we aim to get rid of. After we finished building the vfs api we can switch stacking filesystems to rely on the new posix api and then finally switch the xattr system calls themselves to rely on the posix acl api. Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1] Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
4f353ba4 |
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22-Sep-2022 |
Christian Brauner <brauner@kernel.org> |
acl: add vfs_get_acl() In previous patches we implemented get and set inode operations for all non-stacking filesystems that support posix acls but didn't yet implement get and/or set acl inode operations. This specifically affected cifs and 9p. Now we can build a posix acl api based solely on get and set inode operations. We add a new vfs_get_acl() api that can be used to get posix acls. This finally removes all type unsafety and type conversion issues explained in detail in [1] that we aim to get rid of. After we finished building the vfs api we can switch stacking filesystems to rely on the new posix api and then finally switch the xattr system calls themselves to rely on the posix acl api. Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1] Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
e4cc9163 |
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22-Sep-2022 |
Christian Brauner <brauner@kernel.org> |
acl: add vfs_set_acl() In previous patches we implemented get and set inode operations for all non-stacking filesystems that support posix acls but didn't yet implement get and/or set acl inode operations. This specifically affected cifs and 9p. Now we can build a posix acl api based solely on get and set inode operations. We add a new vfs_set_acl() api that can be used to set posix acls. This finally removes all type unsafety and type conversion issues explained in detail in [1] that we aim to get rid of. After we finished building the vfs api we can switch stacking filesystems to rely on the new posix api and then finally switch the xattr system calls themselves to rely on the posix acl api. Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1] Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
cac2f8b8 |
|
22-Sep-2022 |
Christian Brauner <brauner@kernel.org> |
fs: rename current get acl method The current way of setting and getting posix acls through the generic xattr interface is error prone and type unsafe. The vfs needs to interpret and fixup posix acls before storing or reporting it to userspace. Various hacks exist to make this work. The code is hard to understand and difficult to maintain in it's current form. Instead of making this work by hacking posix acls through xattr handlers we are building a dedicated posix acl api around the get and set inode operations. This removes a lot of hackiness and makes the codepaths easier to maintain. A lot of background can be found in [1]. The current inode operation for getting posix acls takes an inode argument but various filesystems (e.g., 9p, cifs, overlayfs) need access to the dentry. In contrast to the ->set_acl() inode operation we cannot simply extend ->get_acl() to take a dentry argument. The ->get_acl() inode operation is called from: acl_permission_check() -> check_acl() -> get_acl() which is part of generic_permission() which in turn is part of inode_permission(). Both generic_permission() and inode_permission() are called in the ->permission() handler of various filesystems (e.g., overlayfs). So simply passing a dentry argument to ->get_acl() would amount to also having to pass a dentry argument to ->permission(). We should avoid this unnecessary change. So instead of extending the existing inode operation rename it from ->get_acl() to ->get_inode_acl() and add a ->get_acl() method later that passes a dentry argument and which filesystems that need access to the dentry can implement instead of ->get_inode_acl(). Filesystems like cifs which allow setting and getting posix acls but not using them for permission checking during lookup can simply not implement ->get_inode_acl(). This is intended to be a non-functional change. Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1] Suggested-by/Inspired-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
138060ba |
|
23-Sep-2022 |
Christian Brauner <brauner@kernel.org> |
fs: pass dentry to set acl method The current way of setting and getting posix acls through the generic xattr interface is error prone and type unsafe. The vfs needs to interpret and fixup posix acls before storing or reporting it to userspace. Various hacks exist to make this work. The code is hard to understand and difficult to maintain in it's current form. Instead of making this work by hacking posix acls through xattr handlers we are building a dedicated posix acl api around the get and set inode operations. This removes a lot of hackiness and makes the codepaths easier to maintain. A lot of background can be found in [1]. Since some filesystem rely on the dentry being available to them when setting posix acls (e.g., 9p and cifs) they cannot rely on set acl inode operation. But since ->set_acl() is required in order to use the generic posix acl xattr handlers filesystems that do not implement this inode operation cannot use the handler and need to implement their own dedicated posix acl handlers. Update the ->set_acl() inode method to take a dentry argument. This allows all filesystems to rely on ->set_acl(). As far as I can tell all codepaths can be switched to rely on the dentry instead of just the inode. Note that the original motivation for passing the dentry separate from the inode instead of just the dentry in the xattr handlers was because of security modules that call security_d_instantiate(). This hook is called during d_instantiate_new(), d_add(), __d_instantiate_anon(), and d_splice_alias() to initialize the inode's security context and possibly to set security.* xattrs. Since this only affects security.* xattrs this is completely irrelevant for posix acls. Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1] Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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#
36f05cab |
|
09-Sep-2022 |
Jeff Layton <jlayton@kernel.org> |
tmpfs: add support for an i_version counter NFSv4 mandates a change attribute to avoid problems with timestamp granularity, which Linux implements using the i_version counter. This is particularly important when the underlying filesystem is fast. Give tmpfs an i_version counter. Since it doesn't have to be persistent, we can just turn on SB_I_VERSION and sprinkle some inode_inc_iversion calls in the right places. Also, while there is no formal spec for xattrs, most implementations update the ctime on setxattr. Fix shmem_xattr_handler_set to update the ctime and bump the i_version appropriately. Link: https://lkml.kernel.org/r/20220909130031.15477-1-jlayton@kernel.org Signed-off-by: Jeff Layton <jlayton@kernel.org> Cc: Chuck Lever <chuck.lever@oracle.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Hugh Dickins <hughd@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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0978c7c4 |
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14-Sep-2022 |
Deming Wang <wangdeming@inspur.com> |
acl: fix the comments of posix_acl_xattr_set remove the double world of 'in'. Signed-off-by: Deming Wang <wangdeming@inspur.com> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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52edb408 |
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29-Aug-2022 |
Christian Brauner <brauner@kernel.org> |
acl: move idmapping handling into posix_acl_xattr_set() The uapi POSIX ACL struct passed through the value argument during setxattr() contains {g,u}id values encoded via ACL_{GROUP,USER} entries that should actually be stored in the form of k{g,u}id_t (See [1] for a long explanation of the issue.). In 0c5fd887d2bb ("acl: move idmapped mount fixup into vfs_{g,s}etxattr()") we took the mount's idmapping into account in order to let overlayfs handle POSIX ACLs on idmapped layers correctly. The fixup is currently performed directly in vfs_setxattr() which piles on top of the earlier hackiness by handling the mount's idmapping and stuff the vfs{g,u}id_t values into the uapi struct as well. While that is all correct and works fine it's just ugly. Now that we have introduced vfs_make_posix_acl() earlier move handling idmapped mounts out of vfs_setxattr() and into the POSIX ACL handler where it belongs. Note that we also need to call vfs_make_posix_acl() for EVM which interpretes POSIX ACLs during security_inode_setxattr(). Leave them a longer comment for future reference. All filesystems that support idmapped mounts via FS_ALLOW_IDMAP use the standard POSIX ACL xattr handlers and are covered by this change. This includes overlayfs which simply calls vfs_{g,s}etxattr(). The following filesystems use custom POSIX ACL xattr handlers: 9p, cifs, ecryptfs, and ntfs3 (and overlayfs but we've covered that in the paragraph above) and none of them support idmapped mounts yet. Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org/ [1] Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org> Reviewed-by: Seth Forshee (DigitalOcean) <sforshee@kernel.org>
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6b70fe06 |
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29-Aug-2022 |
Christian Brauner <brauner@kernel.org> |
acl: add vfs_set_acl_prepare() Various filesystems store POSIX ACLs on the backing store in their uapi format. Such filesystems need to translate from the uapi POSIX ACL format into the VFS format during i_op->get_acl(). The VFS provides the posix_acl_from_xattr() helper for this task. But the usage of posix_acl_from_xattr() is currently ambiguous. It is intended to transform from a uapi POSIX ACL to the VFS represenation. For example, when retrieving POSIX ACLs for permission checking during lookup or when calling getxattr() to retrieve system.posix_acl_{access,default}. Calling posix_acl_from_xattr() during i_op->get_acl() will map the raw {g,u}id values stored as ACL_{GROUP,USER} entries in the uapi POSIX ACL format into k{g,u}id_t in the filesystem's idmapping and return a struct posix_acl ready to be returned to the VFS for caching and to perform permission checks on. However, posix_acl_from_xattr() is also called during setxattr() for all filesystems that rely on VFS provides posix_acl_{access,default}_xattr_handler. The posix_acl_xattr_set() handler which is used for the ->set() method of posix_acl_{access,default}_xattr_handler uses posix_acl_from_xattr() to translate from the uapi POSIX ACL format to the VFS format so that it can be passed to the i_op->set_acl() handler of the filesystem or for direct caching in case no i_op->set_acl() handler is defined. During setxattr() the {g,u}id values stored as ACL_{GROUP,USER} entries in the uapi POSIX ACL format aren't raw {g,u}id values that need to be mapped according to the filesystem's idmapping. Instead they are {g,u}id values in the caller's idmapping which have been generated during posix_acl_fix_xattr_from_user(). In other words, they are k{g,u}id_t which are passed as raw {g,u}id values abusing the uapi POSIX ACL format (Please note that this type safety violation has existed since the introduction of k{g,u}id_t. Please see [1] for more details.). So when posix_acl_from_xattr() is called in posix_acl_xattr_set() the filesystem idmapping is completely irrelevant. Instead, we abuse the initial idmapping to recover the k{g,u}id_t base on the value stored in raw {g,u}id as ACL_{GROUP,USER} in the uapi POSIX ACL format. We need to clearly distinguish betweeen these two operations as it is really easy to confuse for filesystems as can be seen in ntfs3. In order to do this we factor out make_posix_acl() which takes callbacks allowing callers to pass dedicated methods to generate the correct k{g,u}id_t. This is just an internal static helper which is not exposed to any filesystems but it neatly encapsulates the basic logic of walking through a uapi POSIX ACL and returning an allocated VFS POSIX ACL with the correct k{g,u}id_t values. The posix_acl_from_xattr() helper can then be implemented as a simple call to make_posix_acl() with callbacks that generate the correct k{g,u}id_t from the raw {g,u}id values in ACL_{GROUP,USER} entries in the uapi POSIX ACL format as read from the backing store. For setxattr() we add a new helper vfs_set_acl_prepare() which has callbacks to map the POSIX ACLs from the uapi format with the k{g,u}id_t values stored in raw {g,u}id format in ACL_{GROUP,USER} entries into the correct k{g,u}id_t values in the filesystem idmapping. In contrast to posix_acl_from_xattr() the vfs_set_acl_prepare() helper needs to take the mount idmapping into account. The differences are explained in more detail in the kernel doc for the new functions. In follow up patches we will remove all abuses of posix_acl_from_xattr() for setxattr() operations and replace it with calls to vfs_set_acl_prepare(). The new vfs_set_acl_prepare() helper allows us to deal with the ambiguity in how the POSI ACL uapi struct stores {g,u}id values depending on whether this is a getxattr() or setxattr() operation. This also allows us to remove the posix_acl_setxattr_idmapped_mnt() helper reducing the abuse of the POSIX ACL uapi format to pass values that should be distinct types in {g,u}id values stored as ACL_{GROUP,USER} entries. The removal of posix_acl_setxattr_idmapped_mnt() in turn allows us to re-constify the value parameter of vfs_setxattr() which in turn allows us to avoid the nasty cast from a const void pointer to a non-const void pointer on ovl_do_setxattr(). Ultimately, the plan is to get rid of the type violations completely and never pass the values from k{g,u}id_t as raw {g,u}id in ACL_{GROUP,USER} entries in uapi POSIX ACL format. But that's a longer way to go and this is a preparatory step. Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1] Co-Developed-by: Seth Forshee <sforshee@digitalocean.com> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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985a6d0b |
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29-Aug-2022 |
Christian Brauner <brauner@kernel.org> |
acl: return EOPNOTSUPP in posix_acl_fix_xattr_common() Return EOPNOTSUPP when the POSIX ACL version doesn't match and zero if there are no entries. This will allow us to reuse the helper in posix_acl_from_xattr(). This change will have no user visible effects. Fixes: 0c5fd887d2bb ("acl: move idmapped mount fixup into vfs_{g,s}etxattr()") Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org> Reviewed-by: Seth Forshee (DigitalOcean) <sforshee@kernel.org>>
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abfcf55d |
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16-Aug-2022 |
Christian Brauner <brauner@kernel.org> |
acl: handle idmapped mounts for idmapped filesystems Ensure that POSIX ACLs checking, getting, and setting works correctly for filesystems mountable with a filesystem idmapping ("fs_idmapping") that want to support idmapped mounts ("mnt_idmapping"). Note that no filesystems mountable with an fs_idmapping do yet support idmapped mounts. This is required infrastructure work to unblock this. As we explained in detail in [1] the fs_idmapping is irrelevant for getxattr() and setxattr() when mapping the ACL_{GROUP,USER} {g,u}ids stored in the uapi struct posix_acl_xattr_entry in posix_acl_fix_xattr_{from,to}_user(). But for acl_permission_check() and posix_acl_{g,s}etxattr_idmapped_mnt() the fs_idmapping matters. acl_permission_check(): During lookup POSIX ACLs are retrieved directly via i_op->get_acl() and are returned via the kernel internal struct posix_acl which contains e_{g,u}id members of type k{g,u}id_t that already take the fs_idmapping into acccount. For example, a POSIX ACL stored with u4 on the backing store is mapped to k10000004 in the fs_idmapping. The mnt_idmapping remaps the POSIX ACL to k20000004. In order to do that the fs_idmapping needs to be taken into account but that doesn't happen yet (Again, this is a counterfactual currently as fuse doesn't support idmapped mounts currently. It's just used as a convenient example.): fs_idmapping: u0:k10000000:r65536 mnt_idmapping: u0:v20000000:r65536 ACL_USER: k10000004 acl_permission_check() -> check_acl() -> get_acl() -> i_op->get_acl() == fuse_get_acl() -> posix_acl_from_xattr(u0:k10000000:r65536 /* fs_idmapping */, ...) { k10000004 = make_kuid(u0:k10000000:r65536 /* fs_idmapping */, u4 /* ACL_USER */); } -> posix_acl_permission() { -1 = make_vfsuid(u0:v20000000:r65536 /* mnt_idmapping */, &init_user_ns, k10000004); vfsuid_eq_kuid(-1, k10000004 /* caller_fsuid */) } In order to correctly map from the fs_idmapping into mnt_idmapping we require the relevant fs_idmaping to be passed: acl_permission_check() -> check_acl() -> get_acl() -> i_op->get_acl() == fuse_get_acl() -> posix_acl_from_xattr(u0:k10000000:r65536 /* fs_idmapping */, ...) { k10000004 = make_kuid(u0:k10000000:r65536 /* fs_idmapping */, u4 /* ACL_USER */); } -> posix_acl_permission() { v20000004 = make_vfsuid(u0:v20000000:r65536 /* mnt_idmapping */, u0:k10000000:r65536 /* fs_idmapping */, k10000004); vfsuid_eq_kuid(v20000004, k10000004 /* caller_fsuid */) } The initial_idmapping is only correct for the current situation because all filesystems that currently support idmapped mounts do not support being mounted with an fs_idmapping. Note that ovl_get_acl() is used to retrieve the POSIX ACLs from the relevant lower layer and the lower layer's mnt_idmapping needs to be taken into account and so does the fs_idmapping. See 0c5fd887d2bb ("acl: move idmapped mount fixup into vfs_{g,s}etxattr()") for more details. For posix_acl_{g,s}etxattr_idmapped_mnt() it is not as obvious why the fs_idmapping matters as it is for acl_permission_check(). Especially because it doesn't matter for posix_acl_fix_xattr_{from,to}_user() (See [1] for more context.). Because posix_acl_{g,s}etxattr_idmapped_mnt() operate on the uapi struct posix_acl_xattr_entry which contains {g,u}id_t values and thus give the impression that the fs_idmapping is irrelevant as at this point appropriate {g,u}id_t values have seemlingly been generated. As we've stated multiple times this assumption is wrong and in fact the uapi struct posix_acl_xattr_entry is taking idmappings into account depending at what place it is operated on. posix_acl_getxattr_idmapped_mnt() When posix_acl_getxattr_idmapped_mnt() is called the values stored in the uapi struct posix_acl_xattr_entry are mapped according to the fs_idmapping. This happened when they were read from the backing store and then translated from struct posix_acl into the uapi struct posix_acl_xattr_entry during posix_acl_to_xattr(). In other words, the fs_idmapping matters as the values stored as {g,u}id_t in the uapi struct posix_acl_xattr_entry have been generated by it. So we need to take the fs_idmapping into account during make_vfsuid() in posix_acl_getxattr_idmapped_mnt(). posix_acl_setxattr_idmapped_mnt() When posix_acl_setxattr_idmapped_mnt() is called the values stored as {g,u}id_t in uapi struct posix_acl_xattr_entry are intended to be the values that ultimately get turned back into a k{g,u}id_t in posix_acl_from_xattr() (which turns the uapi struct posix_acl_xattr_entry into the kernel internal struct posix_acl). In other words, the fs_idmapping matters as the values stored as {g,u}id_t in the uapi struct posix_acl_xattr_entry are intended to be the values that will be undone in the fs_idmapping when writing to the backing store. So we need to take the fs_idmapping into account during from_vfsuid() in posix_acl_setxattr_idmapped_mnt(). Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1] Fixes: 0c5fd887d2bb ("acl: move idmapped mount fixup into vfs_{g,s}etxattr()") Cc: Seth Forshee <sforshee@digitalocean.com> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org> Reviewed-by: Seth Forshee <sforshee@digitalocean.com> Link: https://lore.kernel.org/r/20220816113514.43304-1-brauner@kernel.org
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8043bffd |
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06-Jul-2022 |
Christian Brauner <brauner@kernel.org> |
acl: make posix_acl_clone() available to overlayfs The ovl_get_acl() function needs to alter the POSIX ACLs retrieved from the lower filesystem. Instead of hand-rolling a overlayfs specific posix_acl_clone() variant allow export it. It's not special and it's not deeply internal anyway. Link: https://lore.kernel.org/r/20220708090134.385160-3-brauner@kernel.org Cc: Seth Forshee <sforshee@digitalocean.com> Cc: Amir Goldstein <amir73il@gmail.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Aleksa Sarai <cyphar@cyphar.com> Cc: Miklos Szeredi <mszeredi@redhat.com> Cc: linux-unionfs@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Seth Forshee <sforshee@digitalocean.com> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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e933c15f |
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08-Jul-2022 |
Christian Brauner <brauner@kernel.org> |
acl: port to vfs{g,u}id_t Port the few remaining pieces to vfs{g,u}id_t and associated type safe helpers. Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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0c5fd887 |
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06-Jul-2022 |
Christian Brauner <brauner@kernel.org> |
acl: move idmapped mount fixup into vfs_{g,s}etxattr() This cycle we added support for mounting overlayfs on top of idmapped mounts. Recently I've started looking into potential corner cases when trying to add additional tests and I noticed that reporting for POSIX ACLs is currently wrong when using idmapped layers with overlayfs mounted on top of it. I'm going to give a rather detailed explanation to both the origin of the problem and the solution. Let's assume the user creates the following directory layout and they have a rootfs /var/lib/lxc/c1/rootfs. The files in this rootfs are owned as you would expect files on your host system to be owned. For example, ~/.bashrc for your regular user would be owned by 1000:1000 and /root/.bashrc would be owned by 0:0. IOW, this is just regular boring filesystem tree on an ext4 or xfs filesystem. The user chooses to set POSIX ACLs using the setfacl binary granting the user with uid 4 read, write, and execute permissions for their .bashrc file: setfacl -m u:4:rwx /var/lib/lxc/c2/rootfs/home/ubuntu/.bashrc Now they to expose the whole rootfs to a container using an idmapped mount. So they first create: mkdir -pv /vol/contpool/{ctrover,merge,lowermap,overmap} mkdir -pv /vol/contpool/ctrover/{over,work} chown 10000000:10000000 /vol/contpool/ctrover/{over,work} The user now creates an idmapped mount for the rootfs: mount-idmapped/mount-idmapped --map-mount=b:0:10000000:65536 \ /var/lib/lxc/c2/rootfs \ /vol/contpool/lowermap This for example makes it so that /var/lib/lxc/c2/rootfs/home/ubuntu/.bashrc which is owned by uid and gid 1000 as being owned by uid and gid 10001000 at /vol/contpool/lowermap/home/ubuntu/.bashrc. Assume the user wants to expose these idmapped mounts through an overlayfs mount to a container. mount -t overlay overlay \ -o lowerdir=/vol/contpool/lowermap, \ upperdir=/vol/contpool/overmap/over, \ workdir=/vol/contpool/overmap/work \ /vol/contpool/merge The user can do this in two ways: (1) Mount overlayfs in the initial user namespace and expose it to the container. (2) Mount overlayfs on top of the idmapped mounts inside of the container's user namespace. Let's assume the user chooses the (1) option and mounts overlayfs on the host and then changes into a container which uses the idmapping 0:10000000:65536 which is the same used for the two idmapped mounts. Now the user tries to retrieve the POSIX ACLs using the getfacl command getfacl -n /vol/contpool/lowermap/home/ubuntu/.bashrc and to their surprise they see: # file: vol/contpool/merge/home/ubuntu/.bashrc # owner: 1000 # group: 1000 user::rw- user:4294967295:rwx group::r-- mask::rwx other::r-- indicating the the uid wasn't correctly translated according to the idmapped mount. The problem is how we currently translate POSIX ACLs. Let's inspect the callchain in this example: idmapped mount /vol/contpool/merge: 0:10000000:65536 caller's idmapping: 0:10000000:65536 overlayfs idmapping (ofs->creator_cred): 0:0:4k /* initial idmapping */ sys_getxattr() -> path_getxattr() -> getxattr() -> do_getxattr() |> vfs_getxattr() | -> __vfs_getxattr() | -> handler->get == ovl_posix_acl_xattr_get() | -> ovl_xattr_get() | -> vfs_getxattr() | -> __vfs_getxattr() | -> handler->get() /* lower filesystem callback */ |> posix_acl_fix_xattr_to_user() { 4 = make_kuid(&init_user_ns, 4); 4 = mapped_kuid_fs(&init_user_ns /* no idmapped mount */, 4); /* FAILURE */ -1 = from_kuid(0:10000000:65536 /* caller's idmapping */, 4); } If the user chooses to use option (2) and mounts overlayfs on top of idmapped mounts inside the container things don't look that much better: idmapped mount /vol/contpool/merge: 0:10000000:65536 caller's idmapping: 0:10000000:65536 overlayfs idmapping (ofs->creator_cred): 0:10000000:65536 sys_getxattr() -> path_getxattr() -> getxattr() -> do_getxattr() |> vfs_getxattr() | -> __vfs_getxattr() | -> handler->get == ovl_posix_acl_xattr_get() | -> ovl_xattr_get() | -> vfs_getxattr() | -> __vfs_getxattr() | -> handler->get() /* lower filesystem callback */ |> posix_acl_fix_xattr_to_user() { 4 = make_kuid(&init_user_ns, 4); 4 = mapped_kuid_fs(&init_user_ns, 4); /* FAILURE */ -1 = from_kuid(0:10000000:65536 /* caller's idmapping */, 4); } As is easily seen the problem arises because the idmapping of the lower mount isn't taken into account as all of this happens in do_gexattr(). But do_getxattr() is always called on an overlayfs mount and inode and thus cannot possible take the idmapping of the lower layers into account. This problem is similar for fscaps but there the translation happens as part of vfs_getxattr() already. Let's walk through an fscaps overlayfs callchain: setcap 'cap_net_raw+ep' /var/lib/lxc/c2/rootfs/home/ubuntu/.bashrc The expected outcome here is that we'll receive the cap_net_raw capability as we are able to map the uid associated with the fscap to 0 within our container. IOW, we want to see 0 as the result of the idmapping translations. If the user chooses option (1) we get the following callchain for fscaps: idmapped mount /vol/contpool/merge: 0:10000000:65536 caller's idmapping: 0:10000000:65536 overlayfs idmapping (ofs->creator_cred): 0:0:4k /* initial idmapping */ sys_getxattr() -> path_getxattr() -> getxattr() -> do_getxattr() -> vfs_getxattr() -> xattr_getsecurity() -> security_inode_getsecurity() ________________________________ -> cap_inode_getsecurity() | | { V | 10000000 = make_kuid(0:0:4k /* overlayfs idmapping */, 10000000); | 10000000 = mapped_kuid_fs(0:0:4k /* no idmapped mount */, 10000000); | /* Expected result is 0 and thus that we own the fscap. */ | 0 = from_kuid(0:10000000:65536 /* caller's idmapping */, 10000000); | } | -> vfs_getxattr_alloc() | -> handler->get == ovl_other_xattr_get() | -> vfs_getxattr() | -> xattr_getsecurity() | -> security_inode_getsecurity() | -> cap_inode_getsecurity() | { | 0 = make_kuid(0:0:4k /* lower s_user_ns */, 0); | 10000000 = mapped_kuid_fs(0:10000000:65536 /* idmapped mount */, 0); | 10000000 = from_kuid(0:0:4k /* overlayfs idmapping */, 10000000); | |____________________________________________________________________| } -> vfs_getxattr_alloc() -> handler->get == /* lower filesystem callback */ And if the user chooses option (2) we get: idmapped mount /vol/contpool/merge: 0:10000000:65536 caller's idmapping: 0:10000000:65536 overlayfs idmapping (ofs->creator_cred): 0:10000000:65536 sys_getxattr() -> path_getxattr() -> getxattr() -> do_getxattr() -> vfs_getxattr() -> xattr_getsecurity() -> security_inode_getsecurity() _______________________________ -> cap_inode_getsecurity() | | { V | 10000000 = make_kuid(0:10000000:65536 /* overlayfs idmapping */, 0); | 10000000 = mapped_kuid_fs(0:0:4k /* no idmapped mount */, 10000000); | /* Expected result is 0 and thus that we own the fscap. */ | 0 = from_kuid(0:10000000:65536 /* caller's idmapping */, 10000000); | } | -> vfs_getxattr_alloc() | -> handler->get == ovl_other_xattr_get() | |-> vfs_getxattr() | -> xattr_getsecurity() | -> security_inode_getsecurity() | -> cap_inode_getsecurity() | { | 0 = make_kuid(0:0:4k /* lower s_user_ns */, 0); | 10000000 = mapped_kuid_fs(0:10000000:65536 /* idmapped mount */, 0); | 0 = from_kuid(0:10000000:65536 /* overlayfs idmapping */, 10000000); | |____________________________________________________________________| } -> vfs_getxattr_alloc() -> handler->get == /* lower filesystem callback */ We can see how the translation happens correctly in those cases as the conversion happens within the vfs_getxattr() helper. For POSIX ACLs we need to do something similar. However, in contrast to fscaps we cannot apply the fix directly to the kernel internal posix acl data structure as this would alter the cached values and would also require a rework of how we currently deal with POSIX ACLs in general which almost never take the filesystem idmapping into account (the noteable exception being FUSE but even there the implementation is special) and instead retrieve the raw values based on the initial idmapping. The correct values are then generated right before returning to userspace. The fix for this is to move taking the mount's idmapping into account directly in vfs_getxattr() instead of having it be part of posix_acl_fix_xattr_to_user(). To this end we split out two small and unexported helpers posix_acl_getxattr_idmapped_mnt() and posix_acl_setxattr_idmapped_mnt(). The former to be called in vfs_getxattr() and the latter to be called in vfs_setxattr(). Let's go back to the original example. Assume the user chose option (1) and mounted overlayfs on top of idmapped mounts on the host: idmapped mount /vol/contpool/merge: 0:10000000:65536 caller's idmapping: 0:10000000:65536 overlayfs idmapping (ofs->creator_cred): 0:0:4k /* initial idmapping */ sys_getxattr() -> path_getxattr() -> getxattr() -> do_getxattr() |> vfs_getxattr() | |> __vfs_getxattr() | | -> handler->get == ovl_posix_acl_xattr_get() | | -> ovl_xattr_get() | | -> vfs_getxattr() | | |> __vfs_getxattr() | | | -> handler->get() /* lower filesystem callback */ | | |> posix_acl_getxattr_idmapped_mnt() | | { | | 4 = make_kuid(&init_user_ns, 4); | | 10000004 = mapped_kuid_fs(0:10000000:65536 /* lower idmapped mount */, 4); | | 10000004 = from_kuid(&init_user_ns, 10000004); | | |_______________________ | | } | | | | | |> posix_acl_getxattr_idmapped_mnt() | | { | | V | 10000004 = make_kuid(&init_user_ns, 10000004); | 10000004 = mapped_kuid_fs(&init_user_ns /* no idmapped mount */, 10000004); | 10000004 = from_kuid(&init_user_ns, 10000004); | } |_________________________________________________ | | | | |> posix_acl_fix_xattr_to_user() | { V 10000004 = make_kuid(0:0:4k /* init_user_ns */, 10000004); /* SUCCESS */ 4 = from_kuid(0:10000000:65536 /* caller's idmapping */, 10000004); } And similarly if the user chooses option (1) and mounted overayfs on top of idmapped mounts inside the container: idmapped mount /vol/contpool/merge: 0:10000000:65536 caller's idmapping: 0:10000000:65536 overlayfs idmapping (ofs->creator_cred): 0:10000000:65536 sys_getxattr() -> path_getxattr() -> getxattr() -> do_getxattr() |> vfs_getxattr() | |> __vfs_getxattr() | | -> handler->get == ovl_posix_acl_xattr_get() | | -> ovl_xattr_get() | | -> vfs_getxattr() | | |> __vfs_getxattr() | | | -> handler->get() /* lower filesystem callback */ | | |> posix_acl_getxattr_idmapped_mnt() | | { | | 4 = make_kuid(&init_user_ns, 4); | | 10000004 = mapped_kuid_fs(0:10000000:65536 /* lower idmapped mount */, 4); | | 10000004 = from_kuid(&init_user_ns, 10000004); | | |_______________________ | | } | | | | | |> posix_acl_getxattr_idmapped_mnt() | | { V | 10000004 = make_kuid(&init_user_ns, 10000004); | 10000004 = mapped_kuid_fs(&init_user_ns /* no idmapped mount */, 10000004); | 10000004 = from_kuid(0(&init_user_ns, 10000004); | |_________________________________________________ | } | | | |> posix_acl_fix_xattr_to_user() | { V 10000004 = make_kuid(0:0:4k /* init_user_ns */, 10000004); /* SUCCESS */ 4 = from_kuid(0:10000000:65536 /* caller's idmappings */, 10000004); } The last remaining problem we need to fix here is ovl_get_acl(). During ovl_permission() overlayfs will call: ovl_permission() -> generic_permission() -> acl_permission_check() -> check_acl() -> get_acl() -> inode->i_op->get_acl() == ovl_get_acl() > get_acl() /* on the underlying filesystem) ->inode->i_op->get_acl() == /*lower filesystem callback */ -> posix_acl_permission() passing through the get_acl request to the underlying filesystem. This will retrieve the acls stored in the lower filesystem without taking the idmapping of the underlying mount into account as this would mean altering the cached values for the lower filesystem. So we block using ACLs for now until we decided on a nice way to fix this. Note this limitation both in the documentation and in the code. The most straightforward solution would be to have ovl_get_acl() simply duplicate the ACLs, update the values according to the idmapped mount and return it to acl_permission_check() so it can be used in posix_acl_permission() forgetting them afterwards. This is a bit heavy handed but fairly straightforward otherwise. Link: https://github.com/brauner/mount-idmapped/issues/9 Link: https://lore.kernel.org/r/20220708090134.385160-2-brauner@kernel.org Cc: Seth Forshee <sforshee@digitalocean.com> Cc: Amir Goldstein <amir73il@gmail.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Aleksa Sarai <cyphar@cyphar.com> Cc: Miklos Szeredi <mszeredi@redhat.com> Cc: linux-unionfs@vger.kernel.org Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Seth Forshee <sforshee@digitalocean.com> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
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705191b0 |
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19-Apr-2022 |
Christian Brauner <brauner@kernel.org> |
fs: fix acl translation Last cycle we extended the idmapped mounts infrastructure to support idmapped mounts of idmapped filesystems (No such filesystem yet exist.). Since then, the meaning of an idmapped mount is a mount whose idmapping is different from the filesystems idmapping. While doing that work we missed to adapt the acl translation helpers. They still assume that checking for the identity mapping is enough. But they need to use the no_idmapping() helper instead. Note, POSIX ACLs are always translated right at the userspace-kernel boundary using the caller's current idmapping and the initial idmapping. The order depends on whether we're coming from or going to userspace. The filesystem's idmapping doesn't matter at the border. Consequently, if a non-idmapped mount is passed we need to make sure to always pass the initial idmapping as the mount's idmapping and not the filesystem idmapping. Since it's irrelevant here it would yield invalid ids and prevent setting acls for filesystems that are mountable in a userns and support posix acls (tmpfs and fuse). I verified the regression reported in [1] and verified that this patch fixes it. A regression test will be added to xfstests in parallel. Link: https://bugzilla.kernel.org/show_bug.cgi?id=215849 [1] Fixes: bd303368b776 ("fs: support mapped mounts of mapped filesystems") Cc: Seth Forshee <sforshee@digitalocean.com> Cc: Christoph Hellwig <hch@lst.de> Cc: <stable@vger.kernel.org> # 5.17 Cc: <regressions@lists.linux.dev> Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
bd303368 |
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02-Dec-2021 |
Christian Brauner <christian.brauner@ubuntu.com> |
fs: support mapped mounts of mapped filesystems In previous patches we added new and modified existing helpers to handle idmapped mounts of filesystems mounted with an idmapping. In this final patch we convert all relevant places in the vfs to actually pass the filesystem's idmapping into these helpers. With this the vfs is in shape to handle idmapped mounts of filesystems mounted with an idmapping. Note that this is just the generic infrastructure. Actually adding support for idmapped mounts to a filesystem mountable with an idmapping is follow-up work. In this patch we extend the definition of an idmapped mount from a mount that that has the initial idmapping attached to it to a mount that has an idmapping attached to it which is not the same as the idmapping the filesystem was mounted with. As before we do not allow the initial idmapping to be attached to a mount. In addition this patch prevents that the idmapping the filesystem was mounted with can be attached to a mount created based on this filesystem. This has multiple reasons and advantages. First, attaching the initial idmapping or the filesystem's idmapping doesn't make much sense as in both cases the values of the i_{g,u}id and other places where k{g,u}ids are used do not change. Second, a user that really wants to do this for whatever reason can just create a separate dedicated identical idmapping to attach to the mount. Third, we can continue to use the initial idmapping as an indicator that a mount is not idmapped allowing us to continue to keep passing the initial idmapping into the mapping helpers to tell them that something isn't an idmapped mount even if the filesystem is mounted with an idmapping. Link: https://lore.kernel.org/r/20211123114227.3124056-11-brauner@kernel.org (v1) Link: https://lore.kernel.org/r/20211130121032.3753852-11-brauner@kernel.org (v2) Link: https://lore.kernel.org/r/20211203111707.3901969-11-brauner@kernel.org Cc: Seth Forshee <sforshee@digitalocean.com> Cc: Amir Goldstein <amir73il@gmail.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> CC: linux-fsdevel@vger.kernel.org Reviewed-by: Seth Forshee <sforshee@digitalocean.com> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
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44720713 |
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02-Dec-2021 |
Christian Brauner <christian.brauner@ubuntu.com> |
fs: use low-level mapping helpers In a few places the vfs needs to interact with bare k{g,u}ids directly instead of struct inode. These are just a few. In previous patches we introduced low-level mapping helpers that are able to support filesystems mounted an idmapping. This patch simply converts the places to use these new helpers. Link: https://lore.kernel.org/r/20211123114227.3124056-7-brauner@kernel.org (v1) Link: https://lore.kernel.org/r/20211130121032.3753852-7-brauner@kernel.org (v2) Link: https://lore.kernel.org/r/20211203111707.3901969-7-brauner@kernel.org Cc: Seth Forshee <sforshee@digitalocean.com> Cc: Amir Goldstein <amir73il@gmail.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> CC: linux-fsdevel@vger.kernel.org Reviewed-by: Seth Forshee <sforshee@digitalocean.com> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
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a793d79e |
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02-Dec-2021 |
Christian Brauner <christian.brauner@ubuntu.com> |
fs: move mapping helpers The low-level mapping helpers were so far crammed into fs.h. They are out of place there. The fs.h header should just contain the higher-level mapping helpers that interact directly with vfs objects such as struct super_block or struct inode and not the bare mapping helpers. Similarly, only vfs and specific fs code shall interact with low-level mapping helpers. And so they won't be made accessible automatically through regular {g,u}id helpers. Link: https://lore.kernel.org/r/20211123114227.3124056-3-brauner@kernel.org (v1) Link: https://lore.kernel.org/r/20211130121032.3753852-3-brauner@kernel.org (v2) Link: https://lore.kernel.org/r/20211203111707.3901969-3-brauner@kernel.org Cc: Seth Forshee <sforshee@digitalocean.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> CC: linux-fsdevel@vger.kernel.org Reviewed-by: Amir Goldstein <amir73il@gmail.com> Reviewed-by: Seth Forshee <sforshee@digitalocean.com> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
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d1cef29a |
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05-Nov-2021 |
Arnd Bergmann <arnd@arndb.de> |
fs/posix_acl.c: avoid -Wempty-body warning The fallthrough comment for an ignored cmpxchg() return value produces a harmless warning with 'make W=1': fs/posix_acl.c: In function 'get_acl': fs/posix_acl.c:127:36: error: suggest braces around empty body in an 'if' statement [-Werror=empty-body] 127 | /* fall through */ ; | ^ Simplify it as a step towards a clean W=1 build. As all architectures define cmpxchg() as a statement expression these days, it is no longer necessary to evaluate its return code, and the if() can just be droped. Link: https://lkml.kernel.org/r/20210927102410.1863853-1-arnd@kernel.org Link: https://lore.kernel.org/all/20210322132103.qiun2rjilnlgztxe@wittgenstein/ Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: James Morris <jamorris@linux.microsoft.com> Cc: Serge Hallyn <serge@hallyn.com> Cc: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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332f606b |
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18-Aug-2021 |
Miklos Szeredi <mszeredi@redhat.com> |
ovl: enable RCU'd ->get_acl() Overlayfs does not cache ACL's (to avoid double caching). Instead it just calls the underlying filesystem's i_op->get_acl(), which will return the cached value, if possible. In rcu path walk, however, get_cached_acl_rcu() is employed to get the value from the cache, which will fail on overlayfs resulting in dropping out of rcu walk mode. This can result in a big performance hit in certain situations. Fix by calling ->get_acl() with rcu=true in case of ACL_DONT_CACHE (which indicates pass-through) Reported-by: garyhuang <zjh.20052005@163.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
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0cad6246 |
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18-Aug-2021 |
Miklos Szeredi <mszeredi@redhat.com> |
vfs: add rcu argument to ->get_acl() callback Add a rcu argument to the ->get_acl() callback to allow get_cached_acl_rcu() to call the ->get_acl() method in the next patch. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
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549c7297 |
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21-Jan-2021 |
Christian Brauner <christian.brauner@ubuntu.com> |
fs: make helpers idmap mount aware Extend some inode methods with an additional user namespace argument. A filesystem that is aware of idmapped mounts will receive the user namespace the mount has been marked with. This can be used for additional permission checking and also to enable filesystems to translate between uids and gids if they need to. We have implemented all relevant helpers in earlier patches. As requested we simply extend the exisiting inode method instead of introducing new ones. This is a little more code churn but it's mostly mechanical and doesnt't leave us with additional inode methods. Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com Cc: Christoph Hellwig <hch@lst.de> Cc: David Howells <dhowells@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
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e65ce2a5 |
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21-Jan-2021 |
Christian Brauner <christian.brauner@ubuntu.com> |
acl: handle idmapped mounts The posix acl permission checking helpers determine whether a caller is privileged over an inode according to the acls associated with the inode. Add helpers that make it possible to handle acls on idmapped mounts. The vfs and the filesystems targeted by this first iteration make use of posix_acl_fix_xattr_from_user() and posix_acl_fix_xattr_to_user() to translate basic posix access and default permissions such as the ACL_USER and ACL_GROUP type according to the initial user namespace (or the superblock's user namespace) to and from the caller's current user namespace. Adapt these two helpers to handle idmapped mounts whereby we either map from or into the mount's user namespace depending on in which direction we're translating. Similarly, cap_convert_nscap() is used by the vfs to translate user namespace and non-user namespace aware filesystem capabilities from the superblock's user namespace to the caller's user namespace. Enable it to handle idmapped mounts by accounting for the mount's user namespace. In addition the fileystems targeted in the first iteration of this patch series make use of the posix_acl_chmod() and, posix_acl_update_mode() helpers. Both helpers perform permission checks on the target inode. Let them handle idmapped mounts. These two helpers are called when posix acls are set by the respective filesystems to handle this case we extend the ->set() method to take an additional user namespace argument to pass the mount's user namespace down. Link: https://lore.kernel.org/r/20210121131959.646623-9-christian.brauner@ubuntu.com Cc: Christoph Hellwig <hch@lst.de> Cc: David Howells <dhowells@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
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21cb47be |
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21-Jan-2021 |
Christian Brauner <christian.brauner@ubuntu.com> |
inode: make init and permission helpers idmapped mount aware The inode_owner_or_capable() helper determines whether the caller is the owner of the inode or is capable with respect to that inode. Allow it to handle idmapped mounts. If the inode is accessed through an idmapped mount it according to the mount's user namespace. Afterwards the checks are identical to non-idmapped mounts. If the initial user namespace is passed nothing changes so non-idmapped mounts will see identical behavior as before. Similarly, allow the inode_init_owner() helper to handle idmapped mounts. It initializes a new inode on idmapped mounts by mapping the fsuid and fsgid of the caller from the mount's user namespace. If the initial user namespace is passed nothing changes so non-idmapped mounts will see identical behavior as before. Link: https://lore.kernel.org/r/20210121131959.646623-7-christian.brauner@ubuntu.com Cc: Christoph Hellwig <hch@lst.de> Cc: David Howells <dhowells@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: James Morris <jamorris@linux.microsoft.com> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
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47291baa |
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21-Jan-2021 |
Christian Brauner <christian.brauner@ubuntu.com> |
namei: make permission helpers idmapped mount aware The two helpers inode_permission() and generic_permission() are used by the vfs to perform basic permission checking by verifying that the caller is privileged over an inode. In order to handle idmapped mounts we extend the two helpers with an additional user namespace argument. On idmapped mounts the two helpers will make sure to map the inode according to the mount's user namespace and then peform identical permission checks to inode_permission() and generic_permission(). If the initial user namespace is passed nothing changes so non-idmapped mounts will see identical behavior as before. Link: https://lore.kernel.org/r/20210121131959.646623-6-christian.brauner@ubuntu.com Cc: Christoph Hellwig <hch@lst.de> Cc: David Howells <dhowells@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: James Morris <jamorris@linux.microsoft.com> Acked-by: Serge Hallyn <serge@hallyn.com> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
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0558c1bf |
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21-Jan-2021 |
Christian Brauner <christian.brauner@ubuntu.com> |
capability: handle idmapped mounts In order to determine whether a caller holds privilege over a given inode the capability framework exposes the two helpers privileged_wrt_inode_uidgid() and capable_wrt_inode_uidgid(). The former verifies that the inode has a mapping in the caller's user namespace and the latter additionally verifies that the caller has the requested capability in their current user namespace. If the inode is accessed through an idmapped mount map it into the mount's user namespace. Afterwards the checks are identical to non-idmapped inodes. If the initial user namespace is passed all operations are a nop so non-idmapped mounts will not see a change in behavior. Link: https://lore.kernel.org/r/20210121131959.646623-5-christian.brauner@ubuntu.com Cc: Christoph Hellwig <hch@lst.de> Cc: David Howells <dhowells@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: James Morris <jamorris@linux.microsoft.com> Acked-by: Serge Hallyn <serge@hallyn.com> Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
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63d72b93 |
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07-Jun-2020 |
Linus Torvalds <torvalds@linux-foundation.org> |
vfs: clean up posix_acl_permission() logic aroudn MAY_NOT_BLOCK posix_acl_permission() does not care about MAY_NOT_BLOCK, and in fact the permission logic internally must not check that bit (it's only for upper layers to decide whether they can block to do IO to look up the acl information or not). But the way the code was written, it _looked_ like it cared, since the function explicitly did not mask that bit off. But it has exactly two callers: one for when that bit is set, which first clears the bit before calling posix_acl_permission(), and the other call site when that bit was clear. So stop the silly games "saving" the MAY_NOT_BLOCK bit that must not be used for the actual permission test, and that currently is pointlessly cleared by the callers when the function itself should just not care. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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e39e773a |
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04-Jan-2020 |
Randy Dunlap <rdunlap@infradead.org> |
fs/posix_acl.c: fix kernel-doc warnings Fix kernel-doc warnings in fs/posix_acl.c. Also fix one typo (setgit -> setgid). fs/posix_acl.c:647: warning: Function parameter or member 'inode' not described in 'posix_acl_update_mode' fs/posix_acl.c:647: warning: Function parameter or member 'mode_p' not described in 'posix_acl_update_mode' fs/posix_acl.c:647: warning: Function parameter or member 'acl' not described in 'posix_acl_update_mode' Link: http://lkml.kernel.org/r/29b0dc46-1f28-a4e5-b1d0-ba2b65629779@infradead.org Fixes: 073931017b49d ("posix_acl: Clear SGID bit when setting file permissions") Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Acked-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: Jan Kara <jack@suse.cz> Cc: Jan Kara <jack@suse.cz> Cc: Andreas Gruenbacher <agruenba@redhat.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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457c8996 |
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19-May-2019 |
Thomas Gleixner <tglx@linutronix.de> |
treewide: Add SPDX license identifier for missed files Add SPDX license identifiers to all files which: - Have no license information of any form - Have EXPORT_.*_SYMBOL_GPL inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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66717260 |
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29-Nov-2017 |
Elena Reshetova <elena.reshetova@intel.com> |
posix_acl: convert posix_acl.a_refcount from atomic_t to refcount_t atomic_t variables are currently used to implement reference counters with the following properties: - counter is initialized to 1 using atomic_set() - a resource is freed upon counter reaching zero - once counter reaches zero, its further increments aren't allowed - counter schema uses basic atomic operations (set, inc, inc_not_zero, dec_and_test, etc.) Such atomic variables should be converted to a newly provided refcount_t type and API that prevents accidental counter overflows and underflows. This is important since overflows and underflows can lead to use-after-free situation and be exploitable. The variable posix_acl.a_refcount is used as pure reference counter. Convert it to refcount_t and fix up the operations. **Important note for maintainers: Some functions from refcount_t API defined in lib/refcount.c have different memory ordering guarantees than their atomic counterparts. The full comparison can be seen in https://lkml.org/lkml/2017/11/15/57 and it is hopefully soon in state to be merged to the documentation tree. Normally the differences should not matter since refcount_t provides enough guarantees to satisfy the refcounting use cases, but in some rare cases it might matter. Please double check that you don't have some undocumented memory guarantees for this variable usage. For the posix_acl.a_refcount it might make a difference in following places: - get_cached_acl(): increment in refcount_inc_not_zero() only guarantees control dependency on success vs. fully ordered atomic counterpart. However this operation is performed under rcu_read_lock(), so this should be fine. - posix_acl_release(): decrement in refcount_dec_and_test() only provides RELEASE ordering and control dependency on success vs. fully ordered atomic counterpart Suggested-by: Kees Cook <keescook@chromium.org> Reviewed-by: David Windsor <dwindsor@gmail.com> Reviewed-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
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5b825c3a |
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02-Feb-2017 |
Ingo Molnar <mingo@kernel.org> |
sched/headers: Prepare to remove <linux/cred.h> inclusion from <linux/sched.h> Add #include <linux/cred.h> dependencies to all .c files rely on sched.h doing that for them. Note that even if the count where we need to add extra headers seems high, it's still a net win, because <linux/sched.h> is included in over 2,200 files ... Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
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497de07d |
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08-Jan-2017 |
Gu Zheng <guzheng1@huawei.com> |
tmpfs: clear S_ISGID when setting posix ACLs This change was missed the tmpfs modification in In CVE-2016-7097 commit 073931017b49 ("posix_acl: Clear SGID bit when setting file permissions") It can test by xfstest generic/375, which failed to clear setgid bit in the following test case on tmpfs: touch $testfile chown 100:100 $testfile chmod 2755 $testfile _runas -u 100 -g 101 -- setfacl -m u::rwx,g::rwx,o::rwx $testfile Signed-off-by: Gu Zheng <guzheng1@huawei.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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2211d5ba |
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27-Sep-2016 |
Andreas Gruenbacher <agruenba@redhat.com> |
posix_acl: xattr representation cleanups Remove the unnecessary typedefs and the zero-length a_entries array in struct posix_acl_xattr_header. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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078cd827 |
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14-Sep-2016 |
Deepa Dinamani <deepa.kernel@gmail.com> |
fs: Replace CURRENT_TIME with current_time() for inode timestamps CURRENT_TIME macro is not appropriate for filesystems as it doesn't use the right granularity for filesystem timestamps. Use current_time() instead. CURRENT_TIME is also not y2038 safe. This is also in preparation for the patch that transitions vfs timestamps to use 64 bit time and hence make them y2038 safe. As part of the effort current_time() will be extended to do range checks. Hence, it is necessary for all file system timestamps to use current_time(). Also, current_time() will be transitioned along with vfs to be y2038 safe. Note that whenever a single call to current_time() is used to change timestamps in different inodes, it is because they share the same time granularity. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Felipe Balbi <balbi@kernel.org> Acked-by: Steven Whitehouse <swhiteho@redhat.com> Acked-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Acked-by: David Sterba <dsterba@suse.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
#
07393101 |
|
19-Sep-2016 |
Jan Kara <jack@suse.cz> |
posix_acl: Clear SGID bit when setting file permissions When file permissions are modified via chmod(2) and the user is not in the owning group or capable of CAP_FSETID, the setgid bit is cleared in inode_change_ok(). Setting a POSIX ACL via setxattr(2) sets the file permissions as well as the new ACL, but doesn't clear the setgid bit in a similar way; this allows to bypass the check in chmod(2). Fix that. References: CVE-2016-7097 Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
|
#
beaf226b |
|
15-Sep-2016 |
Miklos Szeredi <mszeredi@redhat.com> |
posix_acl: don't ignore return value of posix_acl_create_masq() Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Cc: Andreas Gruenbacher <agruenba@redhat.com>
|
#
0d4d717f |
|
27-Jun-2016 |
Eric W. Biederman <ebiederm@xmission.com> |
vfs: Verify acls are valid within superblock's s_user_ns. Update posix_acl_valid to verify that an acl is within a user namespace. Update the callers of posix_acl_valid to pass in an appropriate user namespace. For posix_acl_xattr_set and v9fs_xattr_set_acl pass in inode->i_sb->s_user_ns to posix_acl_valid. For md_unpack_acl pass in &init_user_ns as no inode or superblock is in sight. Acked-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
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#
485e71e8 |
|
22-Jun-2016 |
Andreas Gruenbacher <agruenba@redhat.com> |
posix_acl: Add set_posix_acl Factor out part of posix_acl_xattr_set into a common function that takes a posix_acl, which nfsd can also call. The prototype already exists in include/linux/posix_acl.h. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Cc: stable@vger.kernel.org Cc: Christoph Hellwig <hch@infradead.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
|
#
59301226 |
|
27-May-2016 |
Al Viro <viro@zeniv.linux.org.uk> |
switch xattr_handler->set() to passing dentry and inode separately preparation for similar switch in ->setxattr() (see the next commit for rationale). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
#
b296821a |
|
10-Apr-2016 |
Al Viro <viro@zeniv.linux.org.uk> |
xattr_handler: pass dentry and inode as separate arguments of ->get() ... and do not assume they are already attached to each other Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
#
04c57f45 |
|
24-Mar-2016 |
Andreas Gruenbacher <agruenba@redhat.com> |
posix_acl: Unexport acl_by_type and make it static acl_by_type(inode, type) returns a pointer to either inode->i_acl or inode->i_default_acl depending on type. This is useful in fs/posix_acl.c, but should never have been visible outside that file. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
#
b8a7a3a6 |
|
24-Mar-2016 |
Andreas Gruenbacher <agruenba@redhat.com> |
posix_acl: Inode acl caching fixes When get_acl() is called for an inode whose ACL is not cached yet, the get_acl inode operation is called to fetch the ACL from the filesystem. The inode operation is responsible for updating the cached acl with set_cached_acl(). This is done without locking at the VFS level, so another task can call set_cached_acl() or forget_cached_acl() before the get_acl inode operation gets to calling set_cached_acl(), and then get_acl's call to set_cached_acl() results in caching an outdate ACL. Prevent this from happening by setting the cached ACL pointer to a task-specific sentinel value before calling the get_acl inode operation. Move the responsibility for updating the cached ACL from the get_acl inode operations to get_acl(). There, only set the cached ACL if the sentinel value hasn't changed. The sentinel values are chosen to have odd values. Likewise, the value of ACL_NOT_CACHED is odd. In contrast, ACL object pointers always have an even value (ACLs are aligned in memory). This allows to distinguish uncached ACLs values from ACL objects. In addition, switch from guarding inode->i_acl and inode->i_default_acl upates by the inode->i_lock spinlock to using xchg() and cmpxchg(). Filesystems that do not want ACLs returned from their get_acl inode operations to be cached must call forget_cached_acl() to prevent the VFS from doing so. (Patch written by Al Viro and Andreas Gruenbacher.) Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
764a5c6b |
|
02-Dec-2015 |
Andreas Gruenbacher <agruenba@redhat.com> |
xattr handlers: Simplify list operation Change the list operation to only return whether or not an attribute should be listed. Copying the attribute names into the buffer is moved to the callers. Since the result only depends on the dentry and not on the attribute name, we do not pass the attribute name to list operations. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
#
98e9cb57 |
|
02-Dec-2015 |
Andreas Gruenbacher <agruenba@redhat.com> |
vfs: Distinguish between full xattr names and proper prefixes Add an additional "name" field to struct xattr_handler. When the name is set, the handler matches attributes with exactly that name. When the prefix is set instead, the handler matches attributes with the given prefix and with a non-empty suffix. This patch should avoid bugs like the one fixed in commit c361016a in the future. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: James Morris <james.l.morris@oracle.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
97d79299 |
|
02-Dec-2015 |
Andreas Gruenbacher <agruenba@redhat.com> |
posix acls: Remove duplicate xattr name definitions Remove POSIX_ACL_XATTR_{ACCESS,DEFAULT} and GFS2_POSIX_ACL_{ACCESS,DEFAULT} and replace them with the definitions in <include/uapi/linux/xattr.h>. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: James Morris <james.l.morris@oracle.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
d9a82a04 |
|
04-Oct-2015 |
Andreas Gruenbacher <agruenba@redhat.com> |
xattr handlers: Pass handler to operations instead of flags The xattr_handler operations are currently all passed a file system specific flags value which the operations can use to disambiguate between different handlers; some file systems use that to distinguish the xattr namespace, for example. In some oprations, it would be useful to also have access to the handler prefix. To allow that, pass a pointer to the handler to operations instead of the flags value alone. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
#
dae5f57a |
|
03-Nov-2015 |
Andreas Gruenbacher <agruenba@redhat.com> |
vfs: Fix the posix_acl_xattr_list return value When a filesystem that contains POSIX ACLs is mounted without ACL support (-o noacl), the appropriate behavior is not to list any existing POSIX ACL xattrs. The return value for list xattr handlers in this case is 0, not an error code: several filesystems that use the POSIX ACL xattr handlers do not expect the list operation to fail. Symlinks cannot have ACLs, so posix_acl_xattr_list will never be called for symlinks in the first place. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
c361016a |
|
03-Nov-2015 |
Andreas Gruenbacher <agruenba@redhat.com> |
vfs: Check attribute names in posix acl xattr handers The get and set operations of the POSIX ACL xattr handlers failed to check the attribute names, so all names with "system.posix_acl_access" or "system.posix_acl_default" as a prefix were accepted. Reject invalid names from now on. Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
c0c3a718 |
|
18-Jun-2015 |
Dan Carpenter <dan.carpenter@oracle.com> |
fs/posix_acl.c: make posix_acl_create() safer and cleaner If posix_acl_create() returns an error code then "*acl" and "*default_acl" can be uninitialized or point to freed memory. This is a dangerous thing to do. For example, it causes a problem in ocfs2_reflink(): fs/ocfs2/refcounttree.c:4327 ocfs2_reflink() error: potentially using uninitialized 'default_acl'. I've re-written this so we set the pointers to NULL at the start. I've added a temporary "clone" variable to hold the value of "*acl" until end. Setting them to NULL means means we don't need the "no_acl" label. We may as well remove the "apply_umask" stuff forward and remove that label as well. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Joel Becker <jlbec@evilplan.org> Cc: Mark Fasheh <mfasheh@suse.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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#
bb668734 |
|
17-Mar-2015 |
David Howells <dhowells@redhat.com> |
VFS: assorted d_backing_inode() annotations Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
e36cb0b8 |
|
28-Jan-2015 |
David Howells <dhowells@redhat.com> |
VFS: (Scripted) Convert S_ISLNK/DIR/REG(dentry->d_inode) to d_is_*(dentry) Convert the following where appropriate: (1) S_ISLNK(dentry->d_inode) to d_is_symlink(dentry). (2) S_ISREG(dentry->d_inode) to d_is_reg(dentry). (3) S_ISDIR(dentry->d_inode) to d_is_dir(dentry). This is actually more complicated than it appears as some calls should be converted to d_can_lookup() instead. The difference is whether the directory in question is a real dir with a ->lookup op or whether it's a fake dir with a ->d_automount op. In some circumstances, we can subsume checks for dentry->d_inode not being NULL into this, provided we the code isn't in a filesystem that expects d_inode to be NULL if the dirent really *is* negative (ie. if we're going to use d_inode() rather than d_backing_inode() to get the inode pointer). Note that the dentry type field may be set to something other than DCACHE_MISS_TYPE when d_inode is NULL in the case of unionmount, where the VFS manages the fall-through from a negative dentry to a lower layer. In such a case, the dentry type of the negative union dentry is set to the same as the type of the lower dentry. However, if you know d_inode is not NULL at the call site, then you can use the d_is_xxx() functions even in a filesystem. There is one further complication: a 0,0 chardev dentry may be labelled DCACHE_WHITEOUT_TYPE rather than DCACHE_SPECIAL_TYPE. Strictly, this was intended for special directory entry types that don't have attached inodes. The following perl+coccinelle script was used: use strict; my @callers; open($fd, 'git grep -l \'S_IS[A-Z].*->d_inode\' |') || die "Can't grep for S_ISDIR and co. callers"; @callers = <$fd>; close($fd); unless (@callers) { print "No matches\n"; exit(0); } my @cocci = ( '@@', 'expression E;', '@@', '', '- S_ISLNK(E->d_inode->i_mode)', '+ d_is_symlink(E)', '', '@@', 'expression E;', '@@', '', '- S_ISDIR(E->d_inode->i_mode)', '+ d_is_dir(E)', '', '@@', 'expression E;', '@@', '', '- S_ISREG(E->d_inode->i_mode)', '+ d_is_reg(E)' ); my $coccifile = "tmp.sp.cocci"; open($fd, ">$coccifile") || die $coccifile; print($fd "$_\n") || die $coccifile foreach (@cocci); close($fd); foreach my $file (@callers) { chomp $file; print "Processing ", $file, "\n"; system("spatch", "--sp-file", $coccifile, $file, "--in-place", "--no-show-diff") == 0 || die "spatch failed"; } [AV: overlayfs parts skipped] Signed-off-by: David Howells <dhowells@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
fed0b588 |
|
08-Feb-2015 |
Omar Sandoval <osandov@osandov.com> |
posix_acl: fix reference leaks in posix_acl_create get_acl gets a reference which we must release in the error cases. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Omar Sandoval <osandov@osandov.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
50c6e282 |
|
04-May-2014 |
Christoph Hellwig <hch@lst.de> |
posix_acl: handle NULL ACL in posix_acl_equiv_mode Various filesystems don't bother checking for a NULL ACL in posix_acl_equiv_mode, and thus can dereference a NULL pointer when it gets passed one. This usually happens from the NFS server, as the ACL tools never pass a NULL ACL, but instead of one representing the mode bits. Instead of adding boilerplat to all filesystems put this check into one place, which will allow us to remove the check from other filesystems as well later on. Signed-off-by: Christoph Hellwig <hch@lst.de> Reported-by: Ben Greear <greearb@candelatech.com> Reported-by: Marco Munderloh <munderl@tnt.uni-hannover.de>, Cc: Chuck Lever <chuck.lever@oracle.com> Cc: stable@vger.kernel.org Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
47ba9734 |
|
13-Feb-2014 |
Dan Carpenter <dan.carpenter@oracle.com> |
fs: NULL dereference in posix_acl_to_xattr() This patch moves the dereference of "buffer" after the check for NULL. The only place which passes a NULL parameter is gfs2_set_acl(). Cc: stable <stable@vger.kernel.org> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
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#
789b663a |
|
31-Jan-2014 |
Trond Myklebust <trond.myklebust@primarydata.com> |
fs: get_acl() must be allowed to return EOPNOTSUPP posix_acl_xattr_get requires get_acl() to return EOPNOTSUPP if the filesystem cannot support acls. This is needed for NFS, which can't know whether or not the server supports acls until it tries to get/set one. This patch converts posix_acl_chmod and posix_acl_create to deal with EOPNOTSUPP return values from get_acl(). Reported-by: Russell King <linux@arm.linux.org.uk> Link: http://lkml.kernel.org/r/20140130140834.GW15937@n2100.arm.linux.org.uk Cc: Al Viro viro@zeniv.linux.org.uk> Reviewed-by: Christoph Hellwig <hch@lst.de> Tested-by: Takashi Iwai <tiwai@suse.de> Signed-off-by: Trond Myklebust <trond.myklebust@primarydata.com>
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#
feda821e |
|
20-Dec-2013 |
Christoph Hellwig <hch@infradead.org> |
fs: remove generic_acl And instead convert tmpfs to use the new generic ACL code, with two stub methods provided for in-memory filesystems. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
37bc1539 |
|
20-Dec-2013 |
Christoph Hellwig <hch@infradead.org> |
fs: make posix_acl_create more useful Rename the current posix_acl_created to __posix_acl_create and add a fully featured helper to set up the ACLs on file creation that uses get_acl(). Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
5bf3258f |
|
20-Dec-2013 |
Christoph Hellwig <hch@infradead.org> |
fs: make posix_acl_chmod more useful Rename the current posix_acl_chmod to __posix_acl_chmod and add a fully featured ACL chmod helper that uses the ->set_acl inode operation. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
2aeccbe9 |
|
20-Dec-2013 |
Christoph Hellwig <hch@infradead.org> |
fs: add generic xattr_acl handlers With the ->set_acl inode operation we can implement the Posix ACL xattr handlers in generic code instead of duplicating them all over the tree. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
2982baa2 |
|
20-Dec-2013 |
Christoph Hellwig <hch@infradead.org> |
fs: add get_acl helper Factor out the code to get an ACL either from the inode or disk from check_acl, so that it can be used elsewhere later on. Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
5c8ebd57 |
|
20-Dec-2013 |
Christoph Hellwig <hch@infradead.org> |
fs: merge xattr_acl.c into posix_acl.c Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
949b9c3d |
|
23-Jan-2014 |
Andreas Gruenbacher <agruen@linbit.com> |
userns: relax the posix_acl_valid() checks So far, POSIX ACLs are using a canonical representation that keeps all ACL entries in a strict order; the ACL_USER and ACL_GROUP entries for specific users and groups are ordered by user and group identifier, respectively. The user-space code provides ACL entries in this order; the kernel verifies that the ACL entry order is correct in posix_acl_valid(). User namespaces allow to arbitrary map user and group identifiers which can cause the ACL_USER and ACL_GROUP entry order to differ between user space and the kernel; posix_acl_valid() would then fail. Work around this by allowing ACL_USER and ACL_GROUP entries to be in any order in the kernel. The effect is only minor: file permission checks will pick the first matching ACL_USER entry, and check all matching ACL_GROUP entries. (The libacl user-space library and getfacl / setfacl tools will not create ACLs with duplicate user or group idenfifiers; they will handle ACLs with entries in an arbitrary order correctly.) Signed-off-by: Andreas Gruenbacher <agruen@linbit.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Theodore Tso <tytso@mit.edu> Cc: Christoph Hellwig <hch@infradead.org> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Jan Kara <jack@suse.cz> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
0afaa120 |
|
21-Jan-2014 |
Andrew Morton <akpm@linux-foundation.org> |
posix_acl: uninlining Uninline vast tracts of nested inline functions in include/linux/posix_acl.h. This reduces the text+data+bss size of x86_64 allyesconfig vmlinux by 8026 bytes. The patch also regularises the positioning of the EXPORT_SYMBOLs in posix_acl.c. Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: J. Bruce Fields <bfields@fieldses.org> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Tested-by: Benny Halevy <bhalevy@primarydata.com> Cc: Benny Halevy <bhalevy@panasas.com> Cc: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
2f6f0654 |
|
07-Feb-2012 |
Eric W. Biederman <ebiederm@xmission.com> |
userns: Convert vfs posix_acl support to use kuids and kgids - In setxattr if we are setting a posix acl convert uids and gids from the current user namespace into the initial user namespace, before the xattrs are passed to the underlying filesystem. Untranslatable uids and gids are represented as -1 which posix_acl_from_xattr will represent as INVALID_UID or INVALID_GID. posix_acl_valid will fail if an acl from userspace has any INVALID_UID or INVALID_GID values. In net this guarantees that untranslatable posix acls will not be stored by filesystems. - In getxattr if we are reading a posix acl convert uids and gids from the initial user namespace into the current user namespace. Uids and gids that can not be tranlsated into the current user namespace will be represented as -1. - Replace e_id in struct posix_acl_entry with an anymouns union of e_uid and e_gid. For the short term retain the e_id field until all of the users are converted. - Don't set struct posix_acl.e_id in the cases where the acl type does not use e_id. Greatly reducing the use of ACL_UNDEFINED_ID. - Rework the ordering checks in posix_acl_valid so that I use kuid_t and kgid_t types throughout the code, and so that I don't need arithmetic on uid and gid types. Cc: Theodore Tso <tytso@mit.edu> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andreas Dilger <adilger.kernel@dilger.ca> Cc: Jan Kara <jack@suse.cz> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
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#
630d9c47 |
|
16-Nov-2011 |
Paul Gortmaker <paul.gortmaker@windriver.com> |
fs: reduce the use of module.h wherever possible For files only using THIS_MODULE and/or EXPORT_SYMBOL, map them onto including export.h -- or if the file isn't even using those, then just delete the include. Fix up any implicit include dependencies that were being masked by module.h along the way. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
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#
d124b60a |
|
23-Oct-2011 |
Andreas Gruenbacher <agruen@kernel.org> |
vfs: pass all mask flags check_acl and posix_acl_permission Acked-by: J. Bruce Fields <bfields@redhat.com> Acked-by: David Howells <dhowells@redhat.com> Signed-off-by: Andreas Gruenbacher <agruen@kernel.org> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Christoph Hellwig <hch@lst.de>
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#
86bc704d |
|
23-Jul-2011 |
Al Viro <viro@zeniv.linux.org.uk> |
switch posix_acl_chmod() to umode_t again, that's what all callers pass to it Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
3a5fba19 |
|
23-Jul-2011 |
Al Viro <viro@zeniv.linux.org.uk> |
switch posix_acl_from_mode() to umode_t ... seeing that this is what all callers pass to it anyway. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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#
d6952123 |
|
23-Jul-2011 |
Al Viro <viro@zeniv.linux.org.uk> |
switch posix_acl_equiv_mode() to umode_t * ... so that &inode->i_mode could be passed to it Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
#
d3fb6120 |
|
23-Jul-2011 |
Al Viro <viro@zeniv.linux.org.uk> |
switch posix_acl_create() to umode_t * so we can pass &inode->i_mode to it Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
|
#
60063497 |
|
26-Jul-2011 |
Arun Sharma <asharma@fb.com> |
atomic: use <linux/atomic.h> This allows us to move duplicated code in <asm/atomic.h> (atomic_inc_not_zero() for now) to <linux/atomic.h> Signed-off-by: Arun Sharma <asharma@fb.com> Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: David Miller <davem@davemloft.net> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: Mike Frysinger <vapier@gentoo.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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#
4e34e719 |
|
23-Jul-2011 |
Christoph Hellwig <hch@lst.de> |
fs: take the ACL checks to common code Replace the ->check_acl method with a ->get_acl method that simply reads an ACL from disk after having a cache miss. This means we can replace the ACL checking boilerplate code with a single implementation in namei.c. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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edde854e |
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23-Jul-2011 |
Al Viro <viro@zeniv.linux.org.uk> |
bury posix_acl_..._masq() variants made static; no callers left outside of posix_acl.c. posix_acl_clone() also has lost all external callers and became static... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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826cae2f |
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23-Jul-2011 |
Al Viro <viro@zeniv.linux.org.uk> |
kill boilerplates around posix_acl_create_masq() new helper: posix_acl_create(&acl, gfp, mode_p). Replaces acl with modified clone, on failure releases acl and replaces with NULL. Returns 0 or -ve on error. All callers of posix_acl_create_masq() switched. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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bc26ab5f |
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22-Jul-2011 |
Al Viro <viro@zeniv.linux.org.uk> |
kill boilerplate around posix_acl_chmod_masq() new helper: posix_acl_chmod(&acl, gfp, mode). Replaces acl with modified clone or with NULL if that has failed; returns 0 or -ve on error. All callers of posix_acl_chmod_masq() switched to that - they'd been doing exactly the same thing. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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f61f6da0 |
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20-Jan-2011 |
Chuck Lever <chuck.lever@oracle.com> |
NFS: Prevent memory allocation failure in nfsacl_encode() nfsacl_encode() allocates memory in certain cases. This of course is not guaranteed to work. Since commit 9f06c719 "SUNRPC: New xdr_streams XDR encoder API", the kernel's XDR encoders can't return a result indicating possibly a failure, so a memory allocation failure in nfsacl_encode() has become fatal (ie, the XDR code Oopses) in some cases. However, the allocated memory is a tiny fixed amount, on the order of 40-50 bytes. We can easily use a stack-allocated buffer for this, with only a wee bit of nose-holding. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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da9592ed |
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13-Nov-2008 |
David Howells <dhowells@redhat.com> |
CRED: Wrap task credential accesses in the filesystem subsystem Wrap access to task credentials so that they can be separated more easily from the task_struct during the introduction of COW creds. Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id(). Change some task->e?[ug]id to task_e?[ug]id(). In some places it makes more sense to use RCU directly rather than a convenient wrapper; these will be addressed by later patches. Signed-off-by: David Howells <dhowells@redhat.com> Reviewed-by: James Morris <jmorris@namei.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: James Morris <jmorris@namei.org>
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52978be6 |
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01-Oct-2006 |
Alexey Dobriyan <adobriyan@gmail.com> |
[PATCH] kmemdup: some users Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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dd0fc66f |
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07-Oct-2005 |
Al Viro <viro@ftp.linux.org.uk> |
[PATCH] gfp flags annotations - part 1 - added typedef unsigned int __nocast gfp_t; - replaced __nocast uses for gfp flags with gfp_t - it gives exactly the same warnings as far as sparse is concerned, doesn't change generated code (from gcc point of view we replaced unsigned int with typedef) and documents what's going on far better. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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1da177e4 |
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16-Apr-2005 |
Linus Torvalds <torvalds@ppc970.osdl.org> |
Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
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