IB/core: Removed port validity check from ib_get_cached_subnet_prefix

Removed port validity check from ib_get_cached_subnet_prefix() as this
check is not needed because "port_num" is valid.

Link: https://lore.kernel.org/r/20210616154509.1047-2-anand.a.khoje@oracle.com
Suggested-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Anand Khoje <anand.a.khoje@oracle.com>
Signed-off-by: Haakon Bugge <haakon.bugge@oracle.com>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/core: Fix incorrect print format specifier

There are some '%u' for 'int' and '%d' for 'unsigend int', they should be
fixed.

Link: https://lore.kernel.org/r/1623325232-30900-1-git-send-email-liweihang@huawei.com
Signed-off-by: Wenpeng Liang <liangwenpeng@huawei.com>
Signed-off-by: Weihang Li <liweihang@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA: Support more than 255 rdma ports

Current code uses many different types when dealing with a port of a RDMA
device: u8, unsigned int and u32. Switch to u32 to clean up the logic.

This allows us to make (at least) the core view consistent and use the
same type. Unfortunately not all places can be converted. Many uverbs
functions expect port to be u8 so keep those places in order not to break
UAPIs. HW/Spec defined values must also not be changed.

With the switch to u32 we now can support devices with more than 255
ports. U32_MAX is reserved to make control logic a bit easier to deal
with. As a device with U32_MAX ports probably isn't going to happen any
time soon this seems like a non issue.

When a device with more than 255 ports is created uverbs will report the
RDMA device as having 255 ports as this is the max currently supported.

The verbs interface is not changed yet because the IBTA spec limits the
port size in too many places to be u8 and all applications that relies in
verbs won't be able to cope with this change. At this stage, we are
extending the interfaces that are using vendor channel solely

Once the limitation is lifted mlx5 in switchdev mode will be able to have
thousands of SFs created by the device. As the only instance of an RDMA
device that reports more than 255 ports will be a representor device and
it exposes itself as a RAW Ethernet only device CM/MAD/IPoIB and other
ULPs aren't effected by this change and their sysfs/interfaces that are
exposes to userspace can remain unchanged.

While here cleanup some alignment issues and remove unneeded sanity
checks (mainly in rdmavt),

Link: https://lore.kernel.org/r/20210301070420.439400-1-leon@kernel.org
Signed-off-by: Mark Bloch <mbloch@nvidia.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/core: Ensure security pkey modify is not lost

The following modify sequence (loosely based on ipoib) will lose a pkey
modifcation:

- Modify (pkey index, port)
- Modify (new pkey index, NO port)

After the first modify, the qp_pps list will have saved the pkey and the
unit on the main list.

During the second modify, get_new_pps() will fetch the port from qp_pps
and read the new pkey index from qp_attr->pkey_index. The state will
still be zero, or IB_PORT_PKEY_NOT_VALID. Because of the invalid state,
the new values will never replace the one in the qp pps list, losing the
new pkey.

This happens because the following if statements will never correct the
state because the first term will be false. If the code had been executed,
it would incorrectly overwrite valid values.

if ((qp_attr_mask & IB_QP_PKEY_INDEX) && (qp_attr_mask & IB_QP_PORT))
new_pps->main.state = IB_PORT_PKEY_VALID;

if (!(qp_attr_mask & (IB_QP_PKEY_INDEX | IB_QP_PORT)) && qp_pps) {
new_pps->main.port_num = qp_pps->main.port_num;
new_pps->main.pkey_index = qp_pps->main.pkey_index;
if (qp_pps->main.state != IB_PORT_PKEY_NOT_VALID)
new_pps->main.state = IB_PORT_PKEY_VALID;
}

Fix by joining the two if statements with an or test to see if qp_pps is
non-NULL and in the correct state.

Fixes: 1dd017882e01 ("RDMA/core: Fix protection fault in get_pkey_idx_qp_list")
Link: https://lore.kernel.org/r/20200313124704.14982.55907.stgit@awfm-01.aw.intel.com
Reviewed-by: Kaike Wan <kaike.wan@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/core: Fix pkey and port assignment in get_new_pps

When port is part of the modify mask, then we should take it from the
qp_attr and not from the old pps. Same for PKEY. Otherwise there are
panics in some configurations:

RIP: 0010:get_pkey_idx_qp_list+0x50/0x80 [ib_core]
Code: c7 18 e8 13 04 30 ef 0f b6 43 06 48 69 c0 b8 00 00 00 48 03 85 a0 04 00 00 48 8b 50 20 48 8d 48 20 48 39 ca 74 1a 0f b7 73 04 <66> 39 72 10 75 08 eb 10 66 39 72 10 74 0a 48 8b 12 48 39 ca 75 f2
RSP: 0018:ffffafb3480932f0 EFLAGS: 00010203
RAX: ffff98059ababa10 RBX: ffff980d926e8cc0 RCX: ffff98059ababa30
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff98059ababa28
RBP: ffff98059b940000 R08: 00000000000310c0 R09: ffff97fe47c07480
R10: 0000000000000036 R11: 0000000000000200 R12: 0000000000000071
R13: ffff98059b940000 R14: ffff980d87f948a0 R15: 0000000000000000
FS: 00007f88deb31740(0000) GS:ffff98059f600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000010 CR3: 0000000853e26001 CR4: 00000000001606e0
Call Trace:
port_pkey_list_insert+0x3d/0x1b0 [ib_core]
? kmem_cache_alloc_trace+0x215/0x220
ib_security_modify_qp+0x226/0x3a0 [ib_core]
_ib_modify_qp+0xcf/0x390 [ib_core]
ipoib_init_qp+0x7f/0x200 [ib_ipoib]
? rvt_modify_port+0xd0/0xd0 [rdmavt]
? ib_find_pkey+0x99/0xf0 [ib_core]
ipoib_ib_dev_open_default+0x1a/0x200 [ib_ipoib]
ipoib_ib_dev_open+0x96/0x130 [ib_ipoib]
ipoib_open+0x44/0x130 [ib_ipoib]
__dev_open+0xd1/0x160
__dev_change_flags+0x1ab/0x1f0
dev_change_flags+0x23/0x60
do_setlink+0x328/0xe30
? __nla_validate_parse+0x54/0x900
__rtnl_newlink+0x54e/0x810
? __alloc_pages_nodemask+0x17d/0x320
? page_fault+0x30/0x50
? _cond_resched+0x15/0x30
? kmem_cache_alloc_trace+0x1c8/0x220
rtnl_newlink+0x43/0x60
rtnetlink_rcv_msg+0x28f/0x350
? kmem_cache_alloc+0x1fb/0x200
? _cond_resched+0x15/0x30
? __kmalloc_node_track_caller+0x24d/0x2d0
? rtnl_calcit.isra.31+0x120/0x120
netlink_rcv_skb+0xcb/0x100
netlink_unicast+0x1e0/0x340
netlink_sendmsg+0x317/0x480
? __check_object_size+0x48/0x1d0
sock_sendmsg+0x65/0x80
____sys_sendmsg+0x223/0x260
? copy_msghdr_from_user+0xdc/0x140
___sys_sendmsg+0x7c/0xc0
? skb_dequeue+0x57/0x70
? __inode_wait_for_writeback+0x75/0xe0
? fsnotify_grab_connector+0x45/0x80
? __dentry_kill+0x12c/0x180
__sys_sendmsg+0x58/0xa0
do_syscall_64+0x5b/0x200
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f88de467f10

Link: https://lore.kernel.org/r/20200227125728.100551-1-leon@kernel.org
Cc: <stable@vger.kernel.org>
Fixes: 1dd017882e01 ("RDMA/core: Fix protection fault in get_pkey_idx_qp_list")
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Tested-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/core: Fix use of logical OR in get_new_pps

Clang warns:

../drivers/infiniband/core/security.c:351:41: warning: converting the
enum constant to a boolean [-Wint-in-bool-context]
if (!(qp_attr_mask & (IB_QP_PKEY_INDEX || IB_QP_PORT)) && qp_pps) {
^
1 warning generated.

A bitwise OR should have been used instead.

Fixes: 1dd017882e01 ("RDMA/core: Fix protection fault in get_pkey_idx_qp_list")
Link: https://lore.kernel.org/r/20200217204318.13609-1-natechancellor@gmail.com
Link: https://github.com/ClangBuiltLinux/linux/issues/889
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/core: Fix protection fault in get_pkey_idx_qp_list

We don't need to set pkey as valid in case that user set only one of pkey
index or port number, otherwise it will be resulted in NULL pointer
dereference while accessing to uninitialized pkey list. The following
crash from Syzkaller revealed it.

kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN PTI
CPU: 1 PID: 14753 Comm: syz-executor.2 Not tainted 5.5.0-rc5 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
RIP: 0010:get_pkey_idx_qp_list+0x161/0x2d0
Code: 01 00 00 49 8b 5e 20 4c 39 e3 0f 84 b9 00 00 00 e8 e4 42 6e fe 48
8d 7b 10 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <0f> b6 04
02 84 c0 74 08 3c 01 0f 8e d0 00 00 00 48 8d 7d 04 48 b8
RSP: 0018:ffffc9000bc6f950 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffffff82c8bdec
RDX: 0000000000000002 RSI: ffffc900030a8000 RDI: 0000000000000010
RBP: ffff888112c8ce80 R08: 0000000000000004 R09: fffff5200178df1f
R10: 0000000000000001 R11: fffff5200178df1f R12: ffff888115dc4430
R13: ffff888115da8498 R14: ffff888115dc4410 R15: ffff888115da8000
FS: 00007f20777de700(0000) GS:ffff88811b100000(0000)
knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2f721000 CR3: 00000001173ca002 CR4: 0000000000360ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
port_pkey_list_insert+0xd7/0x7c0
ib_security_modify_qp+0x6fa/0xfc0
_ib_modify_qp+0x8c4/0xbf0
modify_qp+0x10da/0x16d0
ib_uverbs_modify_qp+0x9a/0x100
ib_uverbs_write+0xaa5/0xdf0
__vfs_write+0x7c/0x100
vfs_write+0x168/0x4a0
ksys_write+0xc8/0x200
do_syscall_64+0x9c/0x390
entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: d291f1a65232 ("IB/core: Enforce PKey security on QPs")
Link: https://lore.kernel.org/r/20200212080651.GB679970@unreal
Signed-off-by: Maor Gottlieb <maorg@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Message-Id: <20200212080651.GB679970@unreal>

IB/core: Fix wrong iterating on ports

rdma_for_each_port is already incrementing the iterator's value it
receives therefore, after the first iteration the iterator is increased by
2 which eventually causing wrong queries and possible traces.

Fix the above by removing the old redundant incrementation that was used
before rdma_for_each_port() macro.

Cc: <stable@vger.kernel.org>
Fixes: ea1075edcbab ("RDMA: Add and use rdma_for_each_port")
Link: https://lore.kernel.org/r/20191002122127.17571-1-leon@kernel.org
Signed-off-by: Mohamad Heib <mohamadh@mellanox.com>
Reviewed-by: Erez Alfasi <ereza@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/device: Consolidate ib_device per_port data into one place

There is no reason to have three allocations of per-port data. Combine
them together and make the lifetime for all the per-port data match the
struct ib_device.

Following patches will require more port-specific data, now there is a
good place to put it.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA: Add and use rdma_for_each_port

We have many loops iterating over all of the end port numbers on a struct
ib_device, simplify them with a for_each helper.

Reviewed-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/device: Ensure that security memory is always freed

Since this only frees memory it should be done during the release
callback. Otherwise there are possible error flows where it might not get
called if registration aborts.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/core: Don't register each MAD agent for LSM notifier

When creating many MAD agents in a short period of time, receive packet
processing can be delayed long enough to cause timeouts while new agents
are being added to the atomic notifier chain with IRQs disabled. Notifier
chain registration and unregstration is an O(n) operation. With large
numbers of MAD agents being created and destroyed simultaneously the CPUs
spend too much time with interrupts disabled.

Instead of each MAD agent registering for it's own LSM notification,
maintain a list of agents internally and register once, this registration
already existed for handling the PKeys. This list is write mostly, so a
normal spin lock is used vs a read/write lock. All MAD agents must be
checked, so a single list is used instead of breaking them down per
device.

Notifier calls are done under rcu_read_lock, so there isn't a risk of
similar packet timeouts while checking the MAD agents security settings
when notified.

Signed-off-by: Daniel Jurgens <danielj@mellanox.com>
Reviewed-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/core: Fix potential memory leak while creating MAD agents

If the MAD agents isn't allowed to manage the subnet, or fails to register
for the LSM notifier, the security context is leaked. Free the context in
these cases.

Fixes: 47a2b338fe63 ("IB/core: Enforce security on management datagrams")
Signed-off-by: Daniel Jurgens <danielj@mellanox.com>
Reviewed-by: Parav Pandit <parav@mellanox.com>
Reported-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/core: Unregister notifier before freeing MAD security

If the notifier runs after the security context is freed an access of
freed memory can occur.

Fixes: 47a2b338fe63 ("IB/core: Enforce security on management datagrams")
Signed-off-by: Daniel Jurgens <danielj@mellanox.com>
Reviewed-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA: Start use ib_device_ops

Make all the required change to start use the ib_device_ops structure.

Signed-off-by: Kamal Heib <kamalheib1@gmail.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/core: Use dev_name instead of ibdev->name

These return the same thing but dev_name is a more conventional use of the
kernel API.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Reviewed-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>

IB/core: Use CONFIG_SECURITY_INFINIBAND to compile out security code

Make security.c depends on CONFIG_SECURITY_INFINIBAND.

Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/core: Verify that QP is security enabled in create and destroy

The XRC target QP create flow sets up qp_sec only if there is an IB link with
LSM security enabled. However, several other related uAPI entry points blindly
follow the qp_sec NULL pointer, resulting in a possible oops.

Check for NULL before using qp_sec.

Cc: <stable@vger.kernel.org> # v4.12
Fixes: d291f1a65232 ("IB/core: Enforce PKey security on QPs")
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Moni Shoua <monis@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/core: Avoid exporting module internal function

ib_security_modify_qp and ib_security_pkey_access are core internal
function. So avoid exporting them.
ib_security_pkey_access is used only when secuirty hooks are enabled so
avoid defining it otherwise.

Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/core: Don't enforce PKey security on SMI MADs

Per the infiniband spec an SMI MAD can have any PKey. Checking the pkey
on SMI MADs is not necessary, and it seems that some older adapters
using the mthca driver don't follow the convention of using the default
PKey, resulting in false denials, or errors querying the PKey cache.

SMI MAD security is still enforced, only agents allowed to manage the
subnet are able to receive or send SMI MADs.

Reported-by: Chris Blake <chrisrblake93@gmail.com>
Cc: <stable@vger.kernel.org> # v4.12
Fixes: 47a2b338fe63 ("IB/core: Enforce security on management datagrams")
Signed-off-by: Daniel Jurgens <danielj@mellanox.com>
Reviewed-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/core: Only enforce security for InfiniBand

For now the only LSM security enforcement mechanism available is
specific to InfiniBand. Bypass enforcement for non-IB link types.

This fixes a regression where modify_qp fails for iWARP because
querying the PKEY returns -EINVAL.

Cc: Paul Moore <paul@paul-moore.com>
Cc: Don Dutile <ddutile@redhat.com>
Cc: stable@vger.kernel.org
Reported-by: Potnuri Bharat Teja <bharat@chelsio.com>
Fixes: d291f1a65232("IB/core: Enforce PKey security on QPs")
Fixes: 47a2b338fe63("IB/core: Enforce security on management datagrams")
Signed-off-by: Daniel Jurgens <danielj@mellanox.com>
Reviewed-by: Parav Pandit <parav@mellanox.com>
Tested-by: Potnuri Bharat Teja <bharat@chelsio.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/core: Only maintain real QPs in the security lists

When modify QP is called on a shared QP update the security context for
the real QP. When security is subsequently enforced the shared QP
handles will be checked as well.

Without this change shared QP handles get added to the port/pkey lists,
which is a bug, because not all shared QP handles will be checked for
access. Also the shared QP security context wouldn't get removed from
the port/pkey lists causing access to free memory and list corruption
when they are destroyed.

Cc: stable@vger.kernel.org
Fixes: d291f1a65232 ("IB/core: Enforce PKey security on QPs")
Signed-off-by: Daniel Jurgens <danielj@mellanox.com>
Reviewed-by: Parav Pandit <parav@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/core: Avoid unnecessary return value check

Since there is nothing done with non zero return value, such check is
avoided.

Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/core: Fix qp_sec use after free access

When security_ib_alloc_security fails, qp->qp_sec memory is freed.
However ib_destroy_qp still tries to access this memory which result
in kernel crash. So its initialized to NULL to avoid such access.

Fixes: d291f1a65232 ("IB/core: Enforce PKey security on QPs")
Signed-off-by: Parav Pandit <parav@mellanox.com>
Reviewed-by: Daniel Jurgens <danielj@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/core: Fix uninitialized variable use in check_qp_port_pkey_settings

Check the return value from get_pkey_and_subnet_prefix to prevent using
uninitialized variables.

Fixes: d291f1a65232 ("IB/core: Enforce PKey security on QPs")
Signed-off-by: Daniel Jurgens <danielj@mellanox.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>

IB/core: Enforce security on management datagrams

Allocate and free a security context when creating and destroying a MAD
agent. This context is used for controlling access to PKeys and sending
and receiving SMPs.

When sending or receiving a MAD check that the agent has permission to
access the PKey for the Subnet Prefix of the port.

During MAD and snoop agent registration for SMI QPs check that the
calling process has permission to access the manage the subnet and
register a callback with the LSM to be notified of policy changes. When
notificaiton of a policy change occurs recheck permission and set a flag
indicating sending and receiving SMPs is allowed.

When sending and receiving MADs check that the agent has access to the
SMI if it's on an SMI QP. Because security policy can change it's
possible permission was allowed when creating the agent, but no longer
is.

Signed-off-by: Daniel Jurgens <danielj@mellanox.com>
Acked-by: Doug Ledford <dledford@redhat.com>
[PM: remove the LSM hook init code]
Signed-off-by: Paul Moore <paul@paul-moore.com>

IB/core: Enforce PKey security on QPs

Add new LSM hooks to allocate and free security contexts and check for
permission to access a PKey.

Allocate and free a security context when creating and destroying a QP.
This context is used for controlling access to PKeys.

When a request is made to modify a QP that changes the port, PKey index,
or alternate path, check that the QP has permission for the PKey in the
PKey table index on the subnet prefix of the port. If the QP is shared
make sure all handles to the QP also have access.

Store which port and PKey index a QP is using. After the reset to init
transition the user can modify the port, PKey index and alternate path
independently. So port and PKey settings changes can be a merge of the
previous settings and the new ones.

In order to maintain access control if there are PKey table or subnet
prefix change keep a list of all QPs are using each PKey index on
each port. If a change occurs all QPs using that device and port must
have access enforced for the new cache settings.

These changes add a transaction to the QP modify process. Association
with the old port and PKey index must be maintained if the modify fails,
and must be removed if it succeeds. Association with the new port and
PKey index must be established prior to the modify and removed if the
modify fails.

1. When a QP is modified to a particular Port, PKey index or alternate
path insert that QP into the appropriate lists.

2. Check permission to access the new settings.

3. If step 2 grants access attempt to modify the QP.

4a. If steps 2 and 3 succeed remove any prior associations.

4b. If ether fails remove the new setting associations.

If a PKey table or subnet prefix changes walk the list of QPs and
check that they have permission. If not send the QP to the error state
and raise a fatal error event. If it's a shared QP make sure all the
QPs that share the real_qp have permission as well. If the QP that
owns a security structure is denied access the security structure is
marked as such and the QP is added to an error_list. Once the moving
the QP to error is complete the security structure mark is cleared.

Maintaining the lists correctly turns QP destroy into a transaction.
The hardware driver for the device frees the ib_qp structure, so while
the destroy is in progress the ib_qp pointer in the ib_qp_security
struct is undefined. When the destroy process begins the ib_qp_security
structure is marked as destroying. This prevents any action from being
taken on the QP pointer. After the QP is destroyed successfully it
could still listed on an error_list wait for it to be processed by that
flow before cleaning up the structure.

If the destroy fails the QPs port and PKey settings are reinserted into
the appropriate lists, the destroying flag is cleared, and access control
is enforced, in case there were any cache changes during the destroy
flow.

To keep the security changes isolated a new file is used to hold security
related functionality.

Signed-off-by: Daniel Jurgens <danielj@mellanox.com>
Acked-by: Doug Ledford <dledford@redhat.com>
[PM: merge fixup in ib_verbs.h and uverbs_cmd.c]
Signed-off-by: Paul Moore <paul@paul-moore.com>