llc: call sock_orphan() at release time

syzbot reported an interesting trace [1] caused by a stale sk->sk_wq
pointer in a closed llc socket.

In commit ff7b11aa481f ("net: socket: set sock->sk to NULL after
calling proto_ops::release()") Eric Biggers hinted that some protocols
are missing a sock_orphan(), we need to perform a full audit.

In net-next, I plan to clear sock->sk from sock_orphan() and
amend Eric patch to add a warning.

[1]
BUG: KASAN: slab-use-after-free in list_empty include/linux/list.h:373 [inline]
BUG: KASAN: slab-use-after-free in waitqueue_active include/linux/wait.h:127 [inline]
BUG: KASAN: slab-use-after-free in sock_def_write_space_wfree net/core/sock.c:3384 [inline]
BUG: KASAN: slab-use-after-free in sock_wfree+0x9a8/0x9d0 net/core/sock.c:2468
Read of size 8 at addr ffff88802f4fc880 by task ksoftirqd/1/27

CPU: 1 PID: 27 Comm: ksoftirqd/1 Not tainted 6.8.0-rc1-syzkaller-00049-g6098d87eaf31 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:377 [inline]
print_report+0xc4/0x620 mm/kasan/report.c:488
kasan_report+0xda/0x110 mm/kasan/report.c:601
list_empty include/linux/list.h:373 [inline]
waitqueue_active include/linux/wait.h:127 [inline]
sock_def_write_space_wfree net/core/sock.c:3384 [inline]
sock_wfree+0x9a8/0x9d0 net/core/sock.c:2468
skb_release_head_state+0xa3/0x2b0 net/core/skbuff.c:1080
skb_release_all net/core/skbuff.c:1092 [inline]
napi_consume_skb+0x119/0x2b0 net/core/skbuff.c:1404
e1000_unmap_and_free_tx_resource+0x144/0x200 drivers/net/ethernet/intel/e1000/e1000_main.c:1970
e1000_clean_tx_irq drivers/net/ethernet/intel/e1000/e1000_main.c:3860 [inline]
e1000_clean+0x4a1/0x26e0 drivers/net/ethernet/intel/e1000/e1000_main.c:3801
__napi_poll.constprop.0+0xb4/0x540 net/core/dev.c:6576
napi_poll net/core/dev.c:6645 [inline]
net_rx_action+0x956/0xe90 net/core/dev.c:6778
__do_softirq+0x21a/0x8de kernel/softirq.c:553
run_ksoftirqd kernel/softirq.c:921 [inline]
run_ksoftirqd+0x31/0x60 kernel/softirq.c:913
smpboot_thread_fn+0x660/0xa10 kernel/smpboot.c:164
kthread+0x2c6/0x3a0 kernel/kthread.c:388
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242
</TASK>

Allocated by task 5167:
kasan_save_stack+0x33/0x50 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
unpoison_slab_object mm/kasan/common.c:314 [inline]
__kasan_slab_alloc+0x81/0x90 mm/kasan/common.c:340
kasan_slab_alloc include/linux/kasan.h:201 [inline]
slab_post_alloc_hook mm/slub.c:3813 [inline]
slab_alloc_node mm/slub.c:3860 [inline]
kmem_cache_alloc_lru+0x142/0x6f0 mm/slub.c:3879
alloc_inode_sb include/linux/fs.h:3019 [inline]
sock_alloc_inode+0x25/0x1c0 net/socket.c:308
alloc_inode+0x5d/0x220 fs/inode.c:260
new_inode_pseudo+0x16/0x80 fs/inode.c:1005
sock_alloc+0x40/0x270 net/socket.c:634
__sock_create+0xbc/0x800 net/socket.c:1535
sock_create net/socket.c:1622 [inline]
__sys_socket_create net/socket.c:1659 [inline]
__sys_socket+0x14c/0x260 net/socket.c:1706
__do_sys_socket net/socket.c:1720 [inline]
__se_sys_socket net/socket.c:1718 [inline]
__x64_sys_socket+0x72/0xb0 net/socket.c:1718
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b

Freed by task 0:
kasan_save_stack+0x33/0x50 mm/kasan/common.c:47
kasan_save_track+0x14/0x30 mm/kasan/common.c:68
kasan_save_free_info+0x3f/0x60 mm/kasan/generic.c:640
poison_slab_object mm/kasan/common.c:241 [inline]
__kasan_slab_free+0x121/0x1b0 mm/kasan/common.c:257
kasan_slab_free include/linux/kasan.h:184 [inline]
slab_free_hook mm/slub.c:2121 [inline]
slab_free mm/slub.c:4299 [inline]
kmem_cache_free+0x129/0x350 mm/slub.c:4363
i_callback+0x43/0x70 fs/inode.c:249
rcu_do_batch kernel/rcu/tree.c:2158 [inline]
rcu_core+0x819/0x1680 kernel/rcu/tree.c:2433
__do_softirq+0x21a/0x8de kernel/softirq.c:553

Last potentially related work creation:
kasan_save_stack+0x33/0x50 mm/kasan/common.c:47
__kasan_record_aux_stack+0xba/0x100 mm/kasan/generic.c:586
__call_rcu_common.constprop.0+0x9a/0x7b0 kernel/rcu/tree.c:2683
destroy_inode+0x129/0x1b0 fs/inode.c:315
iput_final fs/inode.c:1739 [inline]
iput.part.0+0x560/0x7b0 fs/inode.c:1765
iput+0x5c/0x80 fs/inode.c:1755
dentry_unlink_inode+0x292/0x430 fs/dcache.c:400
__dentry_kill+0x1ca/0x5f0 fs/dcache.c:603
dput.part.0+0x4ac/0x9a0 fs/dcache.c:845
dput+0x1f/0x30 fs/dcache.c:835
__fput+0x3b9/0xb70 fs/file_table.c:384
task_work_run+0x14d/0x240 kernel/task_work.c:180
exit_task_work include/linux/task_work.h:38 [inline]
do_exit+0xa8a/0x2ad0 kernel/exit.c:871
do_group_exit+0xd4/0x2a0 kernel/exit.c:1020
__do_sys_exit_group kernel/exit.c:1031 [inline]
__se_sys_exit_group kernel/exit.c:1029 [inline]
__x64_sys_exit_group+0x3e/0x50 kernel/exit.c:1029
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b

The buggy address belongs to the object at ffff88802f4fc800
which belongs to the cache sock_inode_cache of size 1408
The buggy address is located 128 bytes inside of
freed 1408-byte region [ffff88802f4fc800, ffff88802f4fcd80)

The buggy address belongs to the physical page:
page:ffffea0000bd3e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2f4f8
head:ffffea0000bd3e00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000840 ffff888013b06b40 0000000000000000 0000000000000001
raw: 0000000000000000 0000000080150015 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Reclaimable, gfp_mask 0xd20d0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_RECLAIMABLE), pid 4956, tgid 4956 (sshd), ts 31423924727, free_ts 0
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x2d0/0x350 mm/page_alloc.c:1533
prep_new_page mm/page_alloc.c:1540 [inline]
get_page_from_freelist+0xa28/0x3780 mm/page_alloc.c:3311
__alloc_pages+0x22f/0x2440 mm/page_alloc.c:4567
__alloc_pages_node include/linux/gfp.h:238 [inline]
alloc_pages_node include/linux/gfp.h:261 [inline]
alloc_slab_page mm/slub.c:2190 [inline]
allocate_slab mm/slub.c:2354 [inline]
new_slab+0xcc/0x3a0 mm/slub.c:2407
___slab_alloc+0x4af/0x19a0 mm/slub.c:3540
__slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3625
__slab_alloc_node mm/slub.c:3678 [inline]
slab_alloc_node mm/slub.c:3850 [inline]
kmem_cache_alloc_lru+0x379/0x6f0 mm/slub.c:3879
alloc_inode_sb include/linux/fs.h:3019 [inline]
sock_alloc_inode+0x25/0x1c0 net/socket.c:308
alloc_inode+0x5d/0x220 fs/inode.c:260
new_inode_pseudo+0x16/0x80 fs/inode.c:1005
sock_alloc+0x40/0x270 net/socket.c:634
__sock_create+0xbc/0x800 net/socket.c:1535
sock_create net/socket.c:1622 [inline]
__sys_socket_create net/socket.c:1659 [inline]
__sys_socket+0x14c/0x260 net/socket.c:1706
__do_sys_socket net/socket.c:1720 [inline]
__se_sys_socket net/socket.c:1718 [inline]
__x64_sys_socket+0x72/0xb0 net/socket.c:1718
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xd3/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b
page_owner free stack trace missing

Memory state around the buggy address:
ffff88802f4fc780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88802f4fc800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88802f4fc880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88802f4fc900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88802f4fc980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

Fixes: 43815482370c ("net: sock_def_readable() and friends RCU conversion")
Reported-and-tested-by: syzbot+32b89eaa102b372ff76d@syzkaller.appspotmail.com
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Eric Biggers <ebiggers@google.com>
Cc: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20240126165532.3396702-1-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

llc: make llc_ui_sendmsg() more robust against bonding changes

syzbot was able to trick llc_ui_sendmsg(), allocating an skb with no
headroom, but subsequently trying to push 14 bytes of Ethernet header [1]

Like some others, llc_ui_sendmsg() releases the socket lock before
calling sock_alloc_send_skb().
Then it acquires it again, but does not redo all the sanity checks
that were performed.

This fix:

- Uses LL_RESERVED_SPACE() to reserve space.
- Check all conditions again after socket lock is held again.
- Do not account Ethernet header for mtu limitation.

[1]

skbuff: skb_under_panic: text:ffff800088baa334 len:1514 put:14 head:ffff0000c9c37000 data:ffff0000c9c36ff2 tail:0x5dc end:0x6c0 dev:bond0

kernel BUG at net/core/skbuff.c:193 !
Internal error: Oops - BUG: 00000000f2000800 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 6875 Comm: syz-executor.0 Not tainted 6.7.0-rc8-syzkaller-00101-g0802e17d9aca-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : skb_panic net/core/skbuff.c:189 [inline]
pc : skb_under_panic+0x13c/0x140 net/core/skbuff.c:203
lr : skb_panic net/core/skbuff.c:189 [inline]
lr : skb_under_panic+0x13c/0x140 net/core/skbuff.c:203
sp : ffff800096f97000
x29: ffff800096f97010 x28: ffff80008cc8d668 x27: dfff800000000000
x26: ffff0000cb970c90 x25: 00000000000005dc x24: ffff0000c9c36ff2
x23: ffff0000c9c37000 x22: 00000000000005ea x21: 00000000000006c0
x20: 000000000000000e x19: ffff800088baa334 x18: 1fffe000368261ce
x17: ffff80008e4ed000 x16: ffff80008a8310f8 x15: 0000000000000001
x14: 1ffff00012df2d58 x13: 0000000000000000 x12: 0000000000000000
x11: 0000000000000001 x10: 0000000000ff0100 x9 : e28a51f1087e8400
x8 : e28a51f1087e8400 x7 : ffff80008028f8d0 x6 : 0000000000000000
x5 : 0000000000000001 x4 : 0000000000000001 x3 : ffff800082b78714
x2 : 0000000000000001 x1 : 0000000100000000 x0 : 0000000000000089
Call trace:
skb_panic net/core/skbuff.c:189 [inline]
skb_under_panic+0x13c/0x140 net/core/skbuff.c:203
skb_push+0xf0/0x108 net/core/skbuff.c:2451
eth_header+0x44/0x1f8 net/ethernet/eth.c:83
dev_hard_header include/linux/netdevice.h:3188 [inline]
llc_mac_hdr_init+0x110/0x17c net/llc/llc_output.c:33
llc_sap_action_send_xid_c+0x170/0x344 net/llc/llc_s_ac.c:85
llc_exec_sap_trans_actions net/llc/llc_sap.c:153 [inline]
llc_sap_next_state net/llc/llc_sap.c:182 [inline]
llc_sap_state_process+0x1ec/0x774 net/llc/llc_sap.c:209
llc_build_and_send_xid_pkt+0x12c/0x1c0 net/llc/llc_sap.c:270
llc_ui_sendmsg+0x7bc/0xb1c net/llc/af_llc.c:997
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg net/socket.c:745 [inline]
sock_sendmsg+0x194/0x274 net/socket.c:767
splice_to_socket+0x7cc/0xd58 fs/splice.c:881
do_splice_from fs/splice.c:933 [inline]
direct_splice_actor+0xe4/0x1c0 fs/splice.c:1142
splice_direct_to_actor+0x2a0/0x7e4 fs/splice.c:1088
do_splice_direct+0x20c/0x348 fs/splice.c:1194
do_sendfile+0x4bc/0xc70 fs/read_write.c:1254
__do_sys_sendfile64 fs/read_write.c:1322 [inline]
__se_sys_sendfile64 fs/read_write.c:1308 [inline]
__arm64_sys_sendfile64+0x160/0x3b4 fs/read_write.c:1308
__invoke_syscall arch/arm64/kernel/syscall.c:37 [inline]
invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51
el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136
do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155
el0_svc+0x54/0x158 arch/arm64/kernel/entry-common.c:678
el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696
el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595
Code: aa1803e6 aa1903e7 a90023f5 94792f6a (d4210000)

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-and-tested-by: syzbot+2a7024e9502df538e8ef@syzkaller.appspotmail.com
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20240118183625.4007013-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

llc: Check netns in llc_estab_match() and llc_listener_match().

We will remove this restriction in llc_rcv() in the following patch,
which means that the protocol handler must be aware of netns.

if (!net_eq(dev_net(dev), &init_net))
goto drop;

llc_rcv() fetches llc_type_handlers[llc_pdu_type(skb) - 1] and calls it
if not NULL.

If the PDU type is LLC_DEST_CONN, llc_conn_handler() is called to pass
skb to corresponding sockets. Then, we must look up a proper socket in
the same netns with skb->dev.

llc_conn_handler() calls __llc_lookup() to look up a established or
litening socket by __llc_lookup_established() and llc_lookup_listener().

Both functions iterate on a list and call llc_estab_match() or
llc_listener_match() to check if the socket is the correct destination.
However, these functions do not check netns.

Also, bind() and connect() call llc_establish_connection(), which
finally calls __llc_lookup_established(), to check if there is a
conflicting socket.

Let's test netns in llc_estab_match() and llc_listener_match().

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>

sock: Remove ->sendpage*() in favour of sendmsg(MSG_SPLICE_PAGES)

Remove ->sendpage() and ->sendpage_locked(). sendmsg() with
MSG_SPLICE_PAGES should be used instead. This allows multiple pages and
multipage folios to be passed through.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> # for net/can
cc: Jens Axboe <axboe@kernel.dk>
cc: Matthew Wilcox <willy@infradead.org>
cc: linux-afs@lists.infradead.org
cc: mptcp@lists.linux.dev
cc: rds-devel@oss.oracle.com
cc: tipc-discussion@lists.sourceforge.net
cc: virtualization@lists.linux-foundation.org
Link: https://lore.kernel.org/r/20230623225513.2732256-16-dhowells@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: deal with most data-races in sk_wait_event()

__condition is evaluated twice in sk_wait_event() macro.

First invocation is lockless, and reads can race with writes,
as spotted by syzbot.

BUG: KCSAN: data-race in sk_stream_wait_connect / tcp_disconnect

write to 0xffff88812d83d6a0 of 4 bytes by task 9065 on cpu 1:
tcp_disconnect+0x2cd/0xdb0
inet_shutdown+0x19e/0x1f0 net/ipv4/af_inet.c:911
__sys_shutdown_sock net/socket.c:2343 [inline]
__sys_shutdown net/socket.c:2355 [inline]
__do_sys_shutdown net/socket.c:2363 [inline]
__se_sys_shutdown+0xf8/0x140 net/socket.c:2361
__x64_sys_shutdown+0x31/0x40 net/socket.c:2361
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88812d83d6a0 of 4 bytes by task 9040 on cpu 0:
sk_stream_wait_connect+0x1de/0x3a0 net/core/stream.c:75
tcp_sendmsg_locked+0x2e4/0x2120 net/ipv4/tcp.c:1266
tcp_sendmsg+0x30/0x50 net/ipv4/tcp.c:1484
inet6_sendmsg+0x63/0x80 net/ipv6/af_inet6.c:651
sock_sendmsg_nosec net/socket.c:724 [inline]
sock_sendmsg net/socket.c:747 [inline]
__sys_sendto+0x246/0x300 net/socket.c:2142
__do_sys_sendto net/socket.c:2154 [inline]
__se_sys_sendto net/socket.c:2150 [inline]
__x64_sys_sendto+0x78/0x90 net/socket.c:2150
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x00000000 -> 0x00000068

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: rename reference+tracking helpers

Netdev reference helpers have a dev_ prefix for historic
reasons. Renaming the old helpers would be too much churn
but we can rename the tracking ones which are relatively
recent and should be the default for new code.

Rename:
dev_hold_track() -> netdev_hold()
dev_put_track() -> netdev_put()
dev_replace_track() -> netdev_ref_replace()

Link: https://lore.kernel.org/r/20220608043955.919359-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

llc: only change llc->dev when bind() succeeds

My latest patch, attempting to fix the refcount leak in a minimal
way turned out to add a new bug.

Whenever the bind operation fails before we attempt to grab
a reference count on a device, we might release the device refcount
of a prior successful bind() operation.

syzbot was not happy about this [1].

Note to stable teams:

Make sure commit b37a46683739 ("netdevice: add the case if dev is NULL")
is already present in your trees.

[1]
general protection fault, probably for non-canonical address 0xdffffc0000000070: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000380-0x0000000000000387]
CPU: 1 PID: 3590 Comm: syz-executor361 Tainted: G W 5.17.0-syzkaller-04796-g169e77764adc #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:llc_ui_connect+0x400/0xcb0 net/llc/af_llc.c:500
Code: 80 3c 02 00 0f 85 fc 07 00 00 4c 8b a5 38 05 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d bc 24 80 03 00 00 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 a9 07 00 00 49 8b b4 24 80 03 00 00 4c 89 f2 48
RSP: 0018:ffffc900038cfcc0 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: ffff8880756eb600 RCX: 0000000000000000
RDX: 0000000000000070 RSI: ffffc900038cfe3e RDI: 0000000000000380
RBP: ffff888015ee5000 R08: 0000000000000001 R09: ffff888015ee5535
R10: ffffed1002bdcaa6 R11: 0000000000000000 R12: 0000000000000000
R13: ffffc900038cfe37 R14: ffffc900038cfe38 R15: ffff888015ee5012
FS: 0000555555acd300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000280 CR3: 0000000077db6000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
__sys_connect_file+0x155/0x1a0 net/socket.c:1900
__sys_connect+0x161/0x190 net/socket.c:1917
__do_sys_connect net/socket.c:1927 [inline]
__se_sys_connect net/socket.c:1924 [inline]
__x64_sys_connect+0x6f/0xb0 net/socket.c:1924
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f016acb90b9
Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd417947f8 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f016acb90b9
RDX: 0000000000000010 RSI: 0000000020000140 RDI: 0000000000000003
RBP: 00007f016ac7d0a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f016ac7d130
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:llc_ui_connect+0x400/0xcb0 net/llc/af_llc.c:500

Fixes: 764f4eb6846f ("llc: fix netdevice reference leaks in llc_ui_bind()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: 赵子轩 <beraphin@gmail.com>
Cc: Stoyan Manolov <smanolov@suse.de>
Link: https://lore.kernel.org/r/20220325035827.360418-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

llc: fix netdevice reference leaks in llc_ui_bind()

Whenever llc_ui_bind() and/or llc_ui_autobind()
took a reference on a netdevice but subsequently fail,
they must properly release their reference
or risk the infamous message from unregister_netdevice()
at device dismantle.

unregister_netdevice: waiting for eth0 to become free. Usage count = 3

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: 赵子轩 <beraphin@gmail.com>
Reported-by: Stoyan Manolov <smanolov@suse.de>
Link: https://lore.kernel.org/r/20220323004147.1990845-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

llc: add net device refcount tracker

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

net: Remove redundant if statements

The 'if (dev)' statement already move into dev_{put , hold}, so remove
redundant if statements.

Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: llc: fix skb_over_panic

Syzbot reported skb_over_panic() in llc_pdu_init_as_xid_cmd(). The
problem was in wrong LCC header manipulations.

Syzbot's reproducer tries to send XID packet. llc_ui_sendmsg() is
doing following steps:

1. skb allocation with size = len + header size
len is passed from userpace and header size
is 3 since addr->sllc_xid is set.

2. skb_reserve() for header_len = 3
3. filling all other space with memcpy_from_msg()

Ok, at this moment we have fully loaded skb, only headers needs to be
filled.

Then code comes to llc_sap_action_send_xid_c(). This function pushes 3
bytes for LLC PDU header and initializes it. Then comes
llc_pdu_init_as_xid_cmd(). It initalizes next 3 bytes *AFTER* LLC PDU
header and call skb_push(skb, 3). This looks wrong for 2 reasons:

1. Bytes rigth after LLC header are user data, so this function
was overwriting payload.

2. skb_push(skb, 3) call can cause skb_over_panic() since
all free space was filled in llc_ui_sendmsg(). (This can
happen is user passed 686 len: 686 + 14 (eth header) + 3 (LLC
header) = 703. SKB_DATA_ALIGN(703) = 704)

So, in this patch I added 2 new private constansts: LLC_PDU_TYPE_U_XID
and LLC_PDU_LEN_U_XID. LLC_PDU_LEN_U_XID is used to correctly reserve
header size to handle LLC + XID case. LLC_PDU_TYPE_U_XID is used by
llc_pdu_header_init() function to push 6 bytes instead of 3. And finally
I removed skb_push() call from llc_pdu_init_as_xid_cmd().

This changes should not affect other parts of LLC, since after
all steps we just transmit buffer.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-and-tested-by: syzbot+5e5a981ad7cc54c4b2b4@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: pass a sockptr_t into ->setsockopt

Rework the remaining setsockopt code to pass a sockptr_t instead of a
plain user pointer. This removes the last remaining set_fs(KERNEL_DS)
outside of architecture specific code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Stefan Schmidt <stefan@datenfreihafen.org> [ieee802154]
Acked-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: llc: kerneldoc fixes

Simple fixes which require no deep knowledge of the code.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

llc: make sure applications use ARPHRD_ETHER

syzbot was to trigger a bug by tricking AF_LLC with
non sensible addr->sllc_arphrd

It seems clear LLC requires an Ethernet device.

Back in commit abf9d537fea2 ("llc: add support for SO_BINDTODEVICE")
Octavian Purdila added possibility for application to use a zero
value for sllc_arphrd, convert it to ARPHRD_ETHER to not cause
regressions on existing applications.

BUG: KASAN: use-after-free in __read_once_size include/linux/compiler.h:199 [inline]
BUG: KASAN: use-after-free in list_empty include/linux/list.h:268 [inline]
BUG: KASAN: use-after-free in waitqueue_active include/linux/wait.h:126 [inline]
BUG: KASAN: use-after-free in wq_has_sleeper include/linux/wait.h:160 [inline]
BUG: KASAN: use-after-free in skwq_has_sleeper include/net/sock.h:2092 [inline]
BUG: KASAN: use-after-free in sock_def_write_space+0x642/0x670 net/core/sock.c:2813
Read of size 8 at addr ffff88801e0b4078 by task ksoftirqd/3/27

CPU: 3 PID: 27 Comm: ksoftirqd/3 Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x197/0x210 lib/dump_stack.c:118
print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374
__kasan_report.cold+0x1b/0x41 mm/kasan/report.c:506
kasan_report+0x12/0x20 mm/kasan/common.c:639
__asan_report_load8_noabort+0x14/0x20 mm/kasan/generic_report.c:135
__read_once_size include/linux/compiler.h:199 [inline]
list_empty include/linux/list.h:268 [inline]
waitqueue_active include/linux/wait.h:126 [inline]
wq_has_sleeper include/linux/wait.h:160 [inline]
skwq_has_sleeper include/net/sock.h:2092 [inline]
sock_def_write_space+0x642/0x670 net/core/sock.c:2813
sock_wfree+0x1e1/0x260 net/core/sock.c:1958
skb_release_head_state+0xeb/0x260 net/core/skbuff.c:652
skb_release_all+0x16/0x60 net/core/skbuff.c:663
__kfree_skb net/core/skbuff.c:679 [inline]
consume_skb net/core/skbuff.c:838 [inline]
consume_skb+0xfb/0x410 net/core/skbuff.c:832
__dev_kfree_skb_any+0xa4/0xd0 net/core/dev.c:2967
dev_kfree_skb_any include/linux/netdevice.h:3650 [inline]
e1000_unmap_and_free_tx_resource.isra.0+0x21b/0x3a0 drivers/net/ethernet/intel/e1000/e1000_main.c:1963
e1000_clean_tx_irq drivers/net/ethernet/intel/e1000/e1000_main.c:3854 [inline]
e1000_clean+0x4cc/0x1d10 drivers/net/ethernet/intel/e1000/e1000_main.c:3796
napi_poll net/core/dev.c:6532 [inline]
net_rx_action+0x508/0x1120 net/core/dev.c:6600
__do_softirq+0x262/0x98c kernel/softirq.c:292
run_ksoftirqd kernel/softirq.c:603 [inline]
run_ksoftirqd+0x8e/0x110 kernel/softirq.c:595
smpboot_thread_fn+0x6a3/0xa40 kernel/smpboot.c:165
kthread+0x361/0x430 kernel/kthread.c:255
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:352

Allocated by task 8247:
save_stack+0x23/0x90 mm/kasan/common.c:72
set_track mm/kasan/common.c:80 [inline]
__kasan_kmalloc mm/kasan/common.c:513 [inline]
__kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:486
kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:521
slab_post_alloc_hook mm/slab.h:584 [inline]
slab_alloc mm/slab.c:3320 [inline]
kmem_cache_alloc+0x121/0x710 mm/slab.c:3484
sock_alloc_inode+0x1c/0x1d0 net/socket.c:240
alloc_inode+0x68/0x1e0 fs/inode.c:230
new_inode_pseudo+0x19/0xf0 fs/inode.c:919
sock_alloc+0x41/0x270 net/socket.c:560
__sock_create+0xc2/0x730 net/socket.c:1384
sock_create net/socket.c:1471 [inline]
__sys_socket+0x103/0x220 net/socket.c:1513
__do_sys_socket net/socket.c:1522 [inline]
__se_sys_socket net/socket.c:1520 [inline]
__ia32_sys_socket+0x73/0xb0 net/socket.c:1520
do_syscall_32_irqs_on arch/x86/entry/common.c:337 [inline]
do_fast_syscall_32+0x27b/0xe16 arch/x86/entry/common.c:408
entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139

Freed by task 17:
save_stack+0x23/0x90 mm/kasan/common.c:72
set_track mm/kasan/common.c:80 [inline]
kasan_set_free_info mm/kasan/common.c:335 [inline]
__kasan_slab_free+0x102/0x150 mm/kasan/common.c:474
kasan_slab_free+0xe/0x10 mm/kasan/common.c:483
__cache_free mm/slab.c:3426 [inline]
kmem_cache_free+0x86/0x320 mm/slab.c:3694
sock_free_inode+0x20/0x30 net/socket.c:261
i_callback+0x44/0x80 fs/inode.c:219
__rcu_reclaim kernel/rcu/rcu.h:222 [inline]
rcu_do_batch kernel/rcu/tree.c:2183 [inline]
rcu_core+0x570/0x1540 kernel/rcu/tree.c:2408
rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2417
__do_softirq+0x262/0x98c kernel/softirq.c:292

The buggy address belongs to the object at ffff88801e0b4000
which belongs to the cache sock_inode_cache of size 1152
The buggy address is located 120 bytes inside of
1152-byte region [ffff88801e0b4000, ffff88801e0b4480)
The buggy address belongs to the page:
page:ffffea0000782d00 refcount:1 mapcount:0 mapping:ffff88807aa59c40 index:0xffff88801e0b4ffd
raw: 00fffe0000000200 ffffea00008e6c88 ffffea0000782d48 ffff88807aa59c40
raw: ffff88801e0b4ffd ffff88801e0b4000 0000000100000003 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff88801e0b3f00: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc
ffff88801e0b3f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88801e0b4000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88801e0b4080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88801e0b4100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

Fixes: abf9d537fea2 ("llc: add support for SO_BINDTODEVICE")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_llc: fix if-statement empty body warning

When debugging via dprintk() is not enabled, make the dprintk()
macro be an empty do-while loop, as is done in
<linux/sunrpc/debug.h>.

This fixes a gcc warning when -Wextra is set:
../net/llc/af_llc.c:974:51: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body]

I have verified that there is not object code change (with gcc 7.5.0).

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: netdev@vger.kernel.org
Cc: "David S. Miller" <davem@davemloft.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: silence data-races on sk_backlog.tail

sk->sk_backlog.tail might be read without holding the socket spinlock,
we need to add proper READ_ONCE()/WRITE_ONCE() to silence the warnings.

KCSAN reported :

BUG: KCSAN: data-race in tcp_add_backlog / tcp_recvmsg

write to 0xffff8881265109f8 of 8 bytes by interrupt on cpu 1:
__sk_add_backlog include/net/sock.h:907 [inline]
sk_add_backlog include/net/sock.h:938 [inline]
tcp_add_backlog+0x476/0xce0 net/ipv4/tcp_ipv4.c:1759
tcp_v4_rcv+0x1a70/0x1bd0 net/ipv4/tcp_ipv4.c:1947
ip_protocol_deliver_rcu+0x4d/0x420 net/ipv4/ip_input.c:204
ip_local_deliver_finish+0x110/0x140 net/ipv4/ip_input.c:231
NF_HOOK include/linux/netfilter.h:305 [inline]
NF_HOOK include/linux/netfilter.h:299 [inline]
ip_local_deliver+0x133/0x210 net/ipv4/ip_input.c:252
dst_input include/net/dst.h:442 [inline]
ip_rcv_finish+0x121/0x160 net/ipv4/ip_input.c:413
NF_HOOK include/linux/netfilter.h:305 [inline]
NF_HOOK include/linux/netfilter.h:299 [inline]
ip_rcv+0x18f/0x1a0 net/ipv4/ip_input.c:523
__netif_receive_skb_one_core+0xa7/0xe0 net/core/dev.c:4929
__netif_receive_skb+0x37/0xf0 net/core/dev.c:5043
netif_receive_skb_internal+0x59/0x190 net/core/dev.c:5133
napi_skb_finish net/core/dev.c:5596 [inline]
napi_gro_receive+0x28f/0x330 net/core/dev.c:5629
receive_buf+0x284/0x30b0 drivers/net/virtio_net.c:1061
virtnet_receive drivers/net/virtio_net.c:1323 [inline]
virtnet_poll+0x436/0x7d0 drivers/net/virtio_net.c:1428
napi_poll net/core/dev.c:6311 [inline]
net_rx_action+0x3ae/0xa90 net/core/dev.c:6379
__do_softirq+0x115/0x33f kernel/softirq.c:292
invoke_softirq kernel/softirq.c:373 [inline]
irq_exit+0xbb/0xe0 kernel/softirq.c:413
exiting_irq arch/x86/include/asm/apic.h:536 [inline]
do_IRQ+0xa6/0x180 arch/x86/kernel/irq.c:263
ret_from_intr+0x0/0x19
native_safe_halt+0xe/0x10 arch/x86/kernel/paravirt.c:71
arch_cpu_idle+0x1f/0x30 arch/x86/kernel/process.c:571
default_idle_call+0x1e/0x40 kernel/sched/idle.c:94
cpuidle_idle_call kernel/sched/idle.c:154 [inline]
do_idle+0x1af/0x280 kernel/sched/idle.c:263
cpu_startup_entry+0x1b/0x20 kernel/sched/idle.c:355
start_secondary+0x208/0x260 arch/x86/kernel/smpboot.c:264
secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:241

read to 0xffff8881265109f8 of 8 bytes by task 8057 on cpu 0:
tcp_recvmsg+0x46e/0x1b40 net/ipv4/tcp.c:2050
inet_recvmsg+0xbb/0x250 net/ipv4/af_inet.c:838
sock_recvmsg_nosec net/socket.c:871 [inline]
sock_recvmsg net/socket.c:889 [inline]
sock_recvmsg+0x92/0xb0 net/socket.c:885
sock_read_iter+0x15f/0x1e0 net/socket.c:967
call_read_iter include/linux/fs.h:1889 [inline]
new_sync_read+0x389/0x4f0 fs/read_write.c:414
__vfs_read+0xb1/0xc0 fs/read_write.c:427
vfs_read fs/read_write.c:461 [inline]
vfs_read+0x143/0x2c0 fs/read_write.c:446
ksys_read+0xd5/0x1b0 fs/read_write.c:587
__do_sys_read fs/read_write.c:597 [inline]
__se_sys_read fs/read_write.c:595 [inline]
__x64_sys_read+0x4c/0x60 fs/read_write.c:595
do_syscall_64+0xcc/0x370 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 8057 Comm: syz-fuzzer Not tainted 5.4.0-rc6+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: use helpers to change sk_ack_backlog

Writers are holding a lock, but many readers do not.

Following patch will add appropriate barriers in
sk_acceptq_removed() and sk_acceptq_added().

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

llc: fix another potential sk_buff leak in llc_ui_sendmsg()

All callers of llc_conn_state_process() except llc_build_and_send_pkt()
(via llc_ui_sendmsg() -> llc_ui_send_data()) assume that it always
consumes a reference to the skb. Fix this caller to do the same.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>

llc: Check address length before reading address field

KMSAN will complain if valid address length passed to bind() is shorter
than sizeof(struct sockaddr_llc) bytes.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>

llc: do not use sk_eat_skb()

syzkaller triggered a use-after-free [1], caused by a combination of
skb_get() in llc_conn_state_process() and usage of sk_eat_skb()

sk_eat_skb() is assuming the skb about to be freed is only used by
the current thread. TCP/DCCP stacks enforce this because current
thread holds the socket lock.

llc_conn_state_process() wants to make sure skb does not disappear,
and holds a reference on the skb it manipulates. But as soon as this
skb is added to socket receive queue, another thread can consume it.

This means that llc must use regular skb_unlink() and kfree_skb()
so that both producer and consumer can safely work on the same skb.

[1]
BUG: KASAN: use-after-free in atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
BUG: KASAN: use-after-free in refcount_read include/linux/refcount.h:43 [inline]
BUG: KASAN: use-after-free in skb_unref include/linux/skbuff.h:967 [inline]
BUG: KASAN: use-after-free in kfree_skb+0xb7/0x580 net/core/skbuff.c:655
Read of size 4 at addr ffff8801d1f6fba4 by task ksoftirqd/1/18

CPU: 1 PID: 18 Comm: ksoftirqd/1 Not tainted 4.19.0-rc8+ #295
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1c4/0x2b6 lib/dump_stack.c:113
print_address_description.cold.8+0x9/0x1ff mm/kasan/report.c:256
kasan_report_error mm/kasan/report.c:354 [inline]
kasan_report.cold.9+0x242/0x309 mm/kasan/report.c:412
check_memory_region_inline mm/kasan/kasan.c:260 [inline]
check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267
kasan_check_read+0x11/0x20 mm/kasan/kasan.c:272
atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
refcount_read include/linux/refcount.h:43 [inline]
skb_unref include/linux/skbuff.h:967 [inline]
kfree_skb+0xb7/0x580 net/core/skbuff.c:655
llc_sap_state_process+0x9b/0x550 net/llc/llc_sap.c:224
llc_sap_rcv+0x156/0x1f0 net/llc/llc_sap.c:297
llc_sap_handler+0x65e/0xf80 net/llc/llc_sap.c:438
llc_rcv+0x79e/0xe20 net/llc/llc_input.c:208
__netif_receive_skb_one_core+0x14d/0x200 net/core/dev.c:4913
__netif_receive_skb+0x2c/0x1e0 net/core/dev.c:5023
process_backlog+0x218/0x6f0 net/core/dev.c:5829
napi_poll net/core/dev.c:6249 [inline]
net_rx_action+0x7c5/0x1950 net/core/dev.c:6315
__do_softirq+0x30c/0xb03 kernel/softirq.c:292
run_ksoftirqd+0x94/0x100 kernel/softirq.c:653
smpboot_thread_fn+0x68b/0xa00 kernel/smpboot.c:164
kthread+0x35a/0x420 kernel/kthread.c:246
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413

Allocated by task 18:
save_stack+0x43/0xd0 mm/kasan/kasan.c:448
set_track mm/kasan/kasan.c:460 [inline]
kasan_kmalloc+0xc7/0xe0 mm/kasan/kasan.c:553
kasan_slab_alloc+0x12/0x20 mm/kasan/kasan.c:490
kmem_cache_alloc_node+0x144/0x730 mm/slab.c:3644
__alloc_skb+0x119/0x770 net/core/skbuff.c:193
alloc_skb include/linux/skbuff.h:995 [inline]
llc_alloc_frame+0xbc/0x370 net/llc/llc_sap.c:54
llc_station_ac_send_xid_r net/llc/llc_station.c:52 [inline]
llc_station_rcv+0x1dc/0x1420 net/llc/llc_station.c:111
llc_rcv+0xc32/0xe20 net/llc/llc_input.c:220
__netif_receive_skb_one_core+0x14d/0x200 net/core/dev.c:4913
__netif_receive_skb+0x2c/0x1e0 net/core/dev.c:5023
process_backlog+0x218/0x6f0 net/core/dev.c:5829
napi_poll net/core/dev.c:6249 [inline]
net_rx_action+0x7c5/0x1950 net/core/dev.c:6315
__do_softirq+0x30c/0xb03 kernel/softirq.c:292

Freed by task 16383:
save_stack+0x43/0xd0 mm/kasan/kasan.c:448
set_track mm/kasan/kasan.c:460 [inline]
__kasan_slab_free+0x102/0x150 mm/kasan/kasan.c:521
kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
__cache_free mm/slab.c:3498 [inline]
kmem_cache_free+0x83/0x290 mm/slab.c:3756
kfree_skbmem+0x154/0x230 net/core/skbuff.c:582
__kfree_skb+0x1d/0x20 net/core/skbuff.c:642
sk_eat_skb include/net/sock.h:2366 [inline]
llc_ui_recvmsg+0xec2/0x1610 net/llc/af_llc.c:882
sock_recvmsg_nosec net/socket.c:794 [inline]
sock_recvmsg+0xd0/0x110 net/socket.c:801
___sys_recvmsg+0x2b6/0x680 net/socket.c:2278
__sys_recvmmsg+0x303/0xb90 net/socket.c:2390
do_sys_recvmmsg+0x181/0x1a0 net/socket.c:2466
__do_sys_recvmmsg net/socket.c:2484 [inline]
__se_sys_recvmmsg net/socket.c:2480 [inline]
__x64_sys_recvmmsg+0xbe/0x150 net/socket.c:2480
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8801d1f6fac0
which belongs to the cache skbuff_head_cache of size 232
The buggy address is located 228 bytes inside of
232-byte region [ffff8801d1f6fac0, ffff8801d1f6fba8)
The buggy address belongs to the page:
page:ffffea000747dbc0 count:1 mapcount:0 mapping:ffff8801d9be7680 index:0xffff8801d1f6fe80
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffffea0007346e88 ffffea000705b108 ffff8801d9be7680
raw: ffff8801d1f6fe80 ffff8801d1f6f0c0 000000010000000b 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff8801d1f6fa80: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
ffff8801d1f6fb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8801d1f6fb80: fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc
^
ffff8801d1f6fc00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8801d1f6fc80: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL

The poll() changes were not well thought out, and completely
unexplained. They also caused a huge performance regression, because
"->poll()" was no longer a trivial file operation that just called down
to the underlying file operations, but instead did at least two indirect
calls.

Indirect calls are sadly slow now with the Spectre mitigation, but the
performance problem could at least be largely mitigated by changing the
"->get_poll_head()" operation to just have a per-file-descriptor pointer
to the poll head instead. That gets rid of one of the new indirections.

But that doesn't fix the new complexity that is completely unwarranted
for the regular case. The (undocumented) reason for the poll() changes
was some alleged AIO poll race fixing, but we don't make the common case
slower and more complex for some uncommon special case, so this all
really needs way more explanations and most likely a fundamental
redesign.

[ This revert is a revert of about 30 different commits, not reverted
individually because that would just be unnecessarily messy - Linus ]

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

net: convert datagram_poll users tp ->poll_mask

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

llc: better deal with too small mtu

syzbot loves to set very small mtu on devices, since it brings joy.
We must make llc_ui_sendmsg() fool proof.

usercopy: Kernel memory overwrite attempt detected to wrapped address (offset 0, size 18446612139802320068)!

kernel BUG at mm/usercopy.c:100!
invalid opcode: 0000 [#1] SMP KASAN
Dumping ftrace buffer:
(ftrace buffer empty)
Modules linked in:
CPU: 0 PID: 17464 Comm: syz-executor1 Not tainted 4.17.0-rc3+ #36
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:usercopy_abort+0xbb/0xbd mm/usercopy.c:88
RSP: 0018:ffff8801868bf800 EFLAGS: 00010282
RAX: 000000000000006c RBX: ffffffff87d2fb00 RCX: 0000000000000000
RDX: 000000000000006c RSI: ffffffff81610731 RDI: ffffed0030d17ef6
RBP: ffff8801868bf858 R08: ffff88018daa4200 R09: ffffed003b5c4fb0
R10: ffffed003b5c4fb0 R11: ffff8801dae27d87 R12: ffffffff87d2f8e0
R13: ffffffff87d2f7a0 R14: ffffffff87d2f7a0 R15: ffffffff87d2f7a0
FS: 00007f56a14ac700(0000) GS:ffff8801dae00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000001b2bc21000 CR3: 00000001abeb1000 CR4: 00000000001426f0
DR0: 0000000020000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000030602
Call Trace:
check_bogus_address mm/usercopy.c:153 [inline]
__check_object_size+0x5d9/0x5d9 mm/usercopy.c:256
check_object_size include/linux/thread_info.h:108 [inline]
check_copy_size include/linux/thread_info.h:139 [inline]
copy_from_iter_full include/linux/uio.h:121 [inline]
memcpy_from_msg include/linux/skbuff.h:3305 [inline]
llc_ui_sendmsg+0x4b1/0x1530 net/llc/af_llc.c:941
sock_sendmsg_nosec net/socket.c:629 [inline]
sock_sendmsg+0xd5/0x120 net/socket.c:639
__sys_sendto+0x3d7/0x670 net/socket.c:1789
__do_sys_sendto net/socket.c:1801 [inline]
__se_sys_sendto net/socket.c:1797 [inline]
__x64_sys_sendto+0xe1/0x1a0 net/socket.c:1797
do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x455979
RSP: 002b:00007f56a14abc68 EFLAGS: 00000246 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007f56a14ac6d4 RCX: 0000000000455979
RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000018
RBP: 000000000072bea0 R08: 00000000200012c0 R09: 0000000000000010
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000548 R14: 00000000006fbf60 R15: 0000000000000000
Code: 55 c0 e8 c0 55 bb ff ff 75 c8 48 8b 55 c0 4d 89 f9 ff 75 d0 4d 89 e8 48 89 d9 4c 89 e6 41 56 48 c7 c7 80 fa d2 87 e8 a0 0b a3 ff <0f> 0b e8 95 55 bb ff e8 c0 a8 f7 ff 8b 95 14 ff ff ff 4d 89 e8
RIP: usercopy_abort+0xbb/0xbd mm/usercopy.c:88 RSP: ffff8801868bf800

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

llc: fix NULL pointer deref for SOCK_ZAPPED

For SOCK_ZAPPED socket, we don't need to care about llc->sap,
so we should just skip these refcount functions in this case.

Fixes: f7e43672683b ("llc: hold llc_sap before release_sock()")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

llc: hold llc_sap before release_sock()

syzbot reported we still access llc->sap in llc_backlog_rcv()
after it is freed in llc_sap_remove_socket():

Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1b9/0x294 lib/dump_stack.c:113
print_address_description+0x6c/0x20b mm/kasan/report.c:256
kasan_report_error mm/kasan/report.c:354 [inline]
kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
__asan_report_load1_noabort+0x14/0x20 mm/kasan/report.c:430
llc_conn_ac_send_sabme_cmd_p_set_x+0x3a8/0x460 net/llc/llc_c_ac.c:785
llc_exec_conn_trans_actions net/llc/llc_conn.c:475 [inline]
llc_conn_service net/llc/llc_conn.c:400 [inline]
llc_conn_state_process+0x4e1/0x13a0 net/llc/llc_conn.c:75
llc_backlog_rcv+0x195/0x1e0 net/llc/llc_conn.c:891
sk_backlog_rcv include/net/sock.h:909 [inline]
__release_sock+0x12f/0x3a0 net/core/sock.c:2335
release_sock+0xa4/0x2b0 net/core/sock.c:2850
llc_ui_release+0xc8/0x220 net/llc/af_llc.c:204

llc->sap is refcount'ed and llc_sap_remove_socket() is paired
with llc_sap_add_socket(). This can be amended by holding its refcount
before llc_sap_remove_socket() and releasing it after release_sock().

Reported-by: <syzbot+6e181fc95081c2cf9051@syzkaller.appspotmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: make getname() functions return length rather than use int* parameter

Changes since v1:
Added changes in these files:
drivers/infiniband/hw/usnic/usnic_transport.c
drivers/staging/lustre/lnet/lnet/lib-socket.c
drivers/target/iscsi/iscsi_target_login.c
drivers/vhost/net.c
fs/dlm/lowcomms.c
fs/ocfs2/cluster/tcp.c
security/tomoyo/network.c

Before:
All these functions either return a negative error indicator,
or store length of sockaddr into "int *socklen" parameter
and return zero on success.

"int *socklen" parameter is awkward. For example, if caller does not
care, it still needs to provide on-stack storage for the value
it does not need.

None of the many FOO_getname() functions of various protocols
ever used old value of *socklen. They always just overwrite it.

This change drops this parameter, and makes all these functions, on success,
return length of sockaddr. It's always >= 0 and can be differentiated
from an error.

Tests in callers are changed from "if (err)" to "if (err < 0)", where needed.

rpc_sockname() lost "int buflen" parameter, since its only use was
to be passed to kernel_getsockname() as &buflen and subsequently
not used in any way.

Userspace API is not changed.

text data bss dec hex filename
30108430 2633624 873672 33615726 200ef6e vmlinux.before.o
30108109 2633612 873672 33615393 200ee21 vmlinux.o

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: David S. Miller <davem@davemloft.net>
CC: linux-kernel@vger.kernel.org
CC: netdev@vger.kernel.org
CC: linux-bluetooth@vger.kernel.org
CC: linux-decnet-user@lists.sourceforge.net
CC: linux-wireless@vger.kernel.org
CC: linux-rdma@vger.kernel.org
CC: linux-sctp@vger.kernel.org
CC: linux-nfs@vger.kernel.org
CC: linux-x25@vger.kernel.org
Signed-off-by: David S. Miller <davem@davemloft.net>

net: llc: add lock_sock in llc_ui_bind to avoid a race condition

There is a race condition in llc_ui_bind if two or more processes/threads
try to bind a same socket.

If more processes/threads bind a same socket success that will lead to
two problems, one is this action is not what we expected, another is
will lead to kernel in unstable status or oops(in my simple test case,
cause llc2.ko can't unload).

The current code is test SOCK_ZAPPED bit to avoid a process to
bind a same socket twice but that is can't avoid more processes/threads
try to bind a same socket at the same time.

So, add lock_sock in llc_ui_bind like others, such as llc_ui_connect.

Signed-off-by: Lin Zhang <xiaolou4617@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mm: Rename SLAB_DESTROY_BY_RCU to SLAB_TYPESAFE_BY_RCU

A group of Linux kernel hackers reported chasing a bug that resulted
from their assumption that SLAB_DESTROY_BY_RCU provided an existence
guarantee, that is, that no block from such a slab would be reallocated
during an RCU read-side critical section. Of course, that is not the
case. Instead, SLAB_DESTROY_BY_RCU only prevents freeing of an entire
slab of blocks.

However, there is a phrase for this, namely "type safety". This commit
therefore renames SLAB_DESTROY_BY_RCU to SLAB_TYPESAFE_BY_RCU in order
to avoid future instances of this sort of confusion.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: <linux-mm@kvack.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
[ paulmck: Add comments mentioning the old name, as requested by Eric
Dumazet, in order to help people familiar with the old name find
the new one. ]
Acked-by: David Rientjes <rientjes@google.com>

net: Work around lockdep limitation in sockets that use sockets

Lockdep issues a circular dependency warning when AFS issues an operation
through AF_RXRPC from a context in which the VFS/VM holds the mmap_sem.

The theory lockdep comes up with is as follows:

(1) If the pagefault handler decides it needs to read pages from AFS, it
calls AFS with mmap_sem held and AFS begins an AF_RXRPC call, but
creating a call requires the socket lock:

mmap_sem must be taken before sk_lock-AF_RXRPC

(2) afs_open_socket() opens an AF_RXRPC socket and binds it. rxrpc_bind()
binds the underlying UDP socket whilst holding its socket lock.
inet_bind() takes its own socket lock:

sk_lock-AF_RXRPC must be taken before sk_lock-AF_INET

(3) Reading from a TCP socket into a userspace buffer might cause a fault
and thus cause the kernel to take the mmap_sem, but the TCP socket is
locked whilst doing this:

sk_lock-AF_INET must be taken before mmap_sem

However, lockdep's theory is wrong in this instance because it deals only
with lock classes and not individual locks. The AF_INET lock in (2) isn't
really equivalent to the AF_INET lock in (3) as the former deals with a
socket entirely internal to the kernel that never sees userspace. This is
a limitation in the design of lockdep.

Fix the general case by:

(1) Double up all the locking keys used in sockets so that one set are
used if the socket is created by userspace and the other set is used
if the socket is created by the kernel.

(2) Store the kern parameter passed to sk_alloc() in a variable in the
sock struct (sk_kern_sock). This informs sock_lock_init(),
sock_init_data() and sk_clone_lock() as to the lock keys to be used.

Note that the child created by sk_clone_lock() inherits the parent's
kern setting.

(3) Add a 'kern' parameter to ->accept() that is analogous to the one
passed in to ->create() that distinguishes whether kernel_accept() or
sys_accept4() was the caller and can be passed to sk_alloc().

Note that a lot of accept functions merely dequeue an already
allocated socket. I haven't touched these as the new socket already
exists before we get the parameter.

Note also that there are a couple of places where I've made the accepted
socket unconditionally kernel-based:

irda_accept()
rds_rcp_accept_one()
tcp_accept_from_sock()

because they follow a sock_create_kern() and accept off of that.

Whilst creating this, I noticed that lustre and ocfs don't create sockets
through sock_create_kern() and thus they aren't marked as for-kernel,
though they appear to be internal. I wonder if these should do that so
that they use the new set of lock keys.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

sched/headers: Prepare to move signal wakeup & sigpending methods from <linux/sched.h> into <linux/sched/signal.h>

Fix up affected files that include this signal functionality via sched.h.

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>

net: fix sleeping for sk_wait_event()

Similar to commit 14135f30e33c ("inet: fix sleeping inside inet_wait_for_connect()"),
sk_wait_event() needs to fix too, because release_sock() is blocking,
it changes the process state back to running after sleep, which breaks
the previous prepare_to_wait().

Switch to the new wait API.

Cc: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

llc: switch type to bool as the timeout is only tested versus 0

(As asked by Dave in Februrary)

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: fix infoleak in llc

The stack object “info” has a total size of 12 bytes. Its last byte
is padding which is not initialized and leaked via “put_cmsg”.

Signed-off-by: Kangjie Lu <kjlu@gatech.edu>
Signed-off-by: David S. Miller <davem@davemloft.net>

af_llc: fix types on llc_ui_wait_for_conn

The timeout is a long, we return it truncated if it is huge. Basically
harmless as the only caller does a boolean check, but tidy it up anyway.

(64bit build tested this time. Thank you 0day)

Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

tcp: fix recv with flags MSG_WAITALL | MSG_PEEK

Currently, tcp_recvmsg enters a busy loop in sk_wait_data if called
with flags = MSG_WAITALL | MSG_PEEK.

sk_wait_data waits for sk_receive_queue not empty, but in this case,
the receive queue is not empty, but does not contain any skb that we
can use.

Add a "last skb seen on receive queue" argument to sk_wait_data, so
that it sleeps until the receive queue has new skbs.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=99461
Link: https://sourceware.org/bugzilla/show_bug.cgi?id=18493
Link: https://bugzilla.redhat.com/show_bug.cgi?id=1205258
Reported-by: Enrico Scholz <rh-bugzilla@ensc.de>
Reported-by: Dan Searle <dan@censornet.com>
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Pass kern from net_proto_family.create to sk_alloc

In preparation for changing how struct net is refcounted
on kernel sockets pass the knowledge that we are creating
a kernel socket from sock_create_kern through to sk_alloc.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Remove iocb argument from sendmsg and recvmsg

After TIPC doesn't depend on iocb argument in its internal
implementations of sendmsg() and recvmsg() hooks defined in proto
structure, no any user is using iocb argument in them at all now.
Then we can drop the redundant iocb argument completely from kinds of
implementations of both sendmsg() and recvmsg() in the entire
networking stack.

Cc: Christoph Hellwig <hch@lst.de>
Suggested-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

new helper: memcpy_from_msg()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

net: Add and use skb_copy_datagram_msg() helper.

This encapsulates all of the skb_copy_datagram_iovec() callers
with call argument signature "skb, offset, msghdr->msg_iov, length".

When we move to iov_iters in the networking, the iov_iter object will
sit in the msghdr.

Having a helper like this means there will be less places to touch
during that transformation.

Based upon descriptions and patch from Al Viro.

Signed-off-by: David S. Miller <davem@davemloft.net>

net_dma: simple removal

Per commit "77873803363c net_dma: mark broken" net_dma is no longer used
and there is no plan to fix it.

This is the mechanical removal of bits in CONFIG_NET_DMA ifdef guards.
Reverting the remainder of the net_dma induced changes is deferred to
subsequent patches.

Marked for stable due to Roman's report of a memory leak in
dma_pin_iovec_pages():

https://lkml.org/lkml/2014/9/3/177

Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: David Whipple <whipple@securedatainnovations.ch>
Cc: Alexander Duyck <alexander.h.duyck@intel.com>
Cc: <stable@vger.kernel.org>
Reported-by: Roman Gushchin <klamm@yandex-team.ru>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

net: add build-time checks for msg->msg_name size

This is a follow-up patch to f3d3342602f8bc ("net: rework recvmsg
handler msg_name and msg_namelen logic").

DECLARE_SOCKADDR validates that the structure we use for writing the
name information to is not larger than the buffer which is reserved
for msg->msg_name (which is 128 bytes). Also use DECLARE_SOCKADDR
consistently in sendmsg code paths.

Signed-off-by: Steffen Hurrle <steffen@hurrle.net>
Suggested-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: llc: fix use after free in llc_ui_recvmsg

While commit 30a584d944fb fixes datagram interface in LLC, a use
after free bug has been introduced for SOCK_STREAM sockets that do
not make use of MSG_PEEK.

The flow is as follow ...

if (!(flags & MSG_PEEK)) {
...
sk_eat_skb(sk, skb, false);
...
}
...
if (used + offset < skb->len)
continue;

... where sk_eat_skb() calls __kfree_skb(). Therefore, cache
original length and work on skb_len to check partial reads.

Fixes: 30a584d944fb ("[LLX]: SOCK_DGRAM interface fixes")
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Stephen Hemminger <stephen@networkplumber.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: rework recvmsg handler msg_name and msg_namelen logic

This patch now always passes msg->msg_namelen as 0. recvmsg handlers must
set msg_namelen to the proper size <= sizeof(struct sockaddr_storage)
to return msg_name to the user.

This prevents numerous uninitialized memory leaks we had in the
recvmsg handlers and makes it harder for new code to accidentally leak
uninitialized memory.

Optimize for the case recvfrom is called with NULL as address. We don't
need to copy the address at all, so set it to NULL before invoking the
recvmsg handler. We can do so, because all the recvmsg handlers must
cope with the case a plain read() is called on them. read() also sets
msg_name to NULL.

Also document these changes in include/linux/net.h as suggested by David
Miller.

Changes since RFC:

Set msg->msg_name = NULL if user specified a NULL in msg_name but had a
non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't
affect sendto as it would bail out earlier while trying to copy-in the
address. It also more naturally reflects the logic by the callers of
verify_iovec.

With this change in place I could remove "
if (!uaddr || msg_sys->msg_namelen == 0)
msg->msg_name = NULL
".

This change does not alter the user visible error logic as we ignore
msg_namelen as long as msg_name is NULL.

Also remove two unnecessary curly brackets in ___sys_recvmsg and change
comments to netdev style.

Cc: David Miller <davem@davemloft.net>
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

llc: Use normal etherdevice.h tests

Convert the llc_<foo> static inlines to the
equivalents from etherdevice.h and remove
the llc_<foo> static inline functions.

llc_mac_null -> is_zero_ether_addr
llc_mac_multicast -> is_multicast_ether_addr
llc_mac_match -> ether_addr_equal

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

llc: Fix missing msg_namelen update in llc_ui_recvmsg()

For stream sockets the code misses to update the msg_namelen member
to 0 and therefore makes net/socket.c leak the local, uninitialized
sockaddr_storage variable to userland -- 128 bytes of kernel stack
memory. The msg_namelen update is also missing for datagram sockets
in case the socket is shutting down during receive.

Fix both issues by setting msg_namelen to 0 early. It will be
updated later if we're going to fill the msg_name member.

Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Allow userns root to control llc, netfilter, netlink, packet, and xfrm

Allow an unpriviled user who has created a user namespace, and then
created a network namespace to effectively use the new network
namespace, by reducing capable(CAP_NET_ADMIN) and
capable(CAP_NET_RAW) calls to be ns_capable(net->user_ns,
CAP_NET_ADMIN), or capable(net->user_ns, CAP_NET_RAW) calls.

Allow creation of af_key sockets.
Allow creation of llc sockets.
Allow creation of af_packet sockets.

Allow sending xfrm netlink control messages.

Allow binding to netlink multicast groups.
Allow sending to netlink multicast groups.
Allow adding and dropping netlink multicast groups.
Allow sending to all netlink multicast groups and port ids.

Allow reading the netfilter SO_IP_SET socket option.
Allow sending netfilter netlink messages.
Allow setting and getting ip_vs netfilter socket options.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

llc: fix info leak via getsockname()

The LLC code wrongly returns 0, i.e. "success", when the socket is
zapped. Together with the uninitialized uaddrlen pointer argument from
sys_getsockname this leads to an arbitrary memory leak of up to 128
bytes kernel stack via the getsockname() syscall.

Return an error instead when the socket is zapped to prevent the info
leak. Also remove the unnecessary memset(0). We don't directly write to
the memory pointed by uaddr but memcpy() a local structure at the end of
the function that is properly initialized.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

llc2: Call llc_station_exit() on llc2_init() failure path

Otherwise the station packet handler will remain registered even though
the module is unloaded.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Fix (nearly-)kernel-doc comments for various functions

Fix incorrect start markers, wrapped summary lines, missing section
breaks, incorrect separators, and some name mismatches.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: include/net/sock.h cleanup

bool/const conversions where possible

__inline__ -> inline

space cleanups

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: delete all instances of special processing for token ring

We are going to delete the Token ring support. This removes any
special processing in the core networking for token ring, (aside
from net/tr.c itself), leaving the drivers and remaining tokenring
support present but inert.

The mass removal of the drivers and net/tr.c will be in a separate
commit, so that the history of these files that we still care
about won't have the giant deletion tied into their history.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

net: Convert net_ratelimit uses to net_<level>_ratelimited

Standardize the net core ratelimited logging functions.

Coalesce formats, align arguments.
Change a printk then vprintk sequence to use printf extension %pV.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: cleanup unsigned to unsigned int

Use of "unsigned int" is preferred to bare "unsigned" in net tree.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

llc: Fix race condition in llc_ui_recvmsg

There is a race on sk_receive_queue between llc_ui_recvmsg and
sock_queue_rcv_skb.

Our current solution is to protect skb_eat in llc_ui_recvmsg
with the queue spinlock.

Signed-off-by: Radu Iliescu <riliescu@ixiacom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

llc: llc_cmsg_rcv was getting called after sk_eat_skb.

Received non stream protocol packets were calling llc_cmsg_rcv that used a
skb after that skb was released by sk_eat_skb. This caused received STP
packets to generate kernel panics.

Signed-off-by: Alexandru Juncu <ajuncu@ixiacom.com>
Signed-off-by: Kunjan Naik <knaik@ixiacom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: RCU conversion of dev_getbyhwaddr() and arp_ioctl()

Le dimanche 05 décembre 2010 à 09:19 +0100, Eric Dumazet a écrit :

> Hmm..
>
> If somebody can explain why RTNL is held in arp_ioctl() (and therefore
> in arp_req_delete()), we might first remove RTNL use in arp_ioctl() so
> that your patch can be applied.
>
> Right now it is not good, because RTNL wont be necessarly held when you
> are going to call arp_invalidate() ?

While doing this analysis, I found a refcount bug in llc, I'll send a
patch for net-2.6

Meanwhile, here is the patch for net-next-2.6

Your patch then can be applied after mine.

Thanks

[PATCH] net: RCU conversion of dev_getbyhwaddr() and arp_ioctl()

dev_getbyhwaddr() was called under RTNL.

Rename it to dev_getbyhwaddr_rcu() and change all its caller to now use
RCU locking instead of RTNL.

Change arp_ioctl() to use RCU instead of RTNL locking.

Note: this fix a dev refcount bug in llc

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

llc: fix a device refcount imbalance

Le dimanche 05 décembre 2010 à 12:23 +0100, Eric Dumazet a écrit :
> Le dimanche 05 décembre 2010 à 09:19 +0100, Eric Dumazet a écrit :
>
> > Hmm..
> >
> > If somebody can explain why RTNL is held in arp_ioctl() (and therefore
> > in arp_req_delete()), we might first remove RTNL use in arp_ioctl() so
> > that your patch can be applied.
> >
> > Right now it is not good, because RTNL wont be necessarly held when you
> > are going to call arp_invalidate() ?
>
> While doing this analysis, I found a refcount bug in llc, I'll send a
> patch for net-2.6

Oh well, of course I must first fix the bug in net-2.6, and wait David
pull the fix in net-next-2.6 before sending this rcu conversion.

Note: this patch should be sent to stable teams (2.6.34 and up)

[PATCH net-2.6] llc: fix a device refcount imbalance

commit abf9d537fea225 (llc: add support for SO_BINDTODEVICE) added one
refcount imbalance in llc_ui_bind(), because dev_getbyhwaddr() doesnt
take a reference on device, while dev_get_by_index() does.

Fix this using RCU locking. And since an RCU conversion will be done for
2.6.38 for dev_getbyhwaddr(), put the rcu_read_lock/unlock exactly at
their final place.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: stable@kernel.org
Cc: Octavian Purdila <opurdila@ixiacom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/llc: make opt unsigned in llc_ui_setsockopt()

The members of struct llc_sock are unsigned so if we pass a negative
value for "opt" it can cause a sign bug. Also it can cause an integer
overflow when we multiply "opt * HZ".

CC: stable@kernel.org
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: sk_sleep() helper

Define a new function to return the waitqueue of a "struct sock".

static inline wait_queue_head_t *sk_sleep(struct sock *sk)
{
return sk->sk_sleep;
}

Change all read occurrences of sk_sleep by a call to this function.

Needed for a future RCU conversion. sk_sleep wont be a field directly
available.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

llc: fix SAP reference counting w.r.t. socket handling

The SAP ref counter gets decremented twice when deleting a socket,
although for all but the first socket of a SAP the SAP ref counter was
incremented only once.

Signed-off-by: Octavian Purdila <opurdila@ixiacom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

llc: convert the socket list to RCU locking

For the reclamation phase we use the SLAB_DESTROY_BY_RCU mechanism,
which require some extra checks in the lookup code:

a) If the current socket was released, reallocated & inserted in
another list it will short circuit the iteration for the current list,
thus we need to restart the lookup.

b) If the current socket was released, reallocated & inserted in the
same list we just need to recheck it matches the look-up criteria and
if not we can skip to the next element.

In this case there is no need to restart the lookup, since sockets are
inserted at the start of the list and the worst that will happen is
that we will iterate throught some of the list elements more then
once.

Note that the /proc and multicast delivery was not yet converted to
RCU, it still uses spinlocks for protection.

Signed-off-by: Octavian Purdila <opurdila@ixiacom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

llc: add support for SO_BINDTODEVICE

Using bind(MAC address) with LLC sockets has O(n) complexity, where n
is the number of interfaces. To overcome this, we add support for
SO_BINDTODEVICE which drops the complexity to O(1).

Signed-off-by: Octavian Purdila <opurdila@ixiacom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

llc: add support for LLC_OPT_PKTINFO

Signed-off-by: Octavian Purdila <opurdila@ixiacom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: use net_eq to compare nets

Generated with the following semantic patch

@@
struct net *n1;
struct net *n2;
@@
- n1 == n2
+ net_eq(n1, n2)

@@
struct net *n1;
struct net *n2;
@@
- n1 != n2
+ !net_eq(n1, n2)

applied over {include,net,drivers/net}.

Signed-off-by: Octavian Purdila <opurdila@ixiacom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: pass kern to net_proto_family create function

The generic __sock_create function has a kern argument which allows the
security system to make decisions based on if a socket is being created by
the kernel or by userspace. This patch passes that flag to the
net_proto_family specific create function, so it can do the same thing.

Signed-off-by: Eric Paris <eparis@redhat.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: mark net_proto_ops as const

All usages of structure net_proto_ops should be declared const.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: Make setsockopt() optlen be unsigned.

This provides safety against negative optlen at the type
level instead of depending upon (sometimes non-trivial)
checks against this sprinkled all over the the place, in
each and every implementation.

Based upon work done by Arjan van de Ven and feedback
from Linus Torvalds.

Signed-off-by: David S. Miller <davem@davemloft.net>

NET: llc, zero sockaddr_llc struct

sllc_arphrd member of sockaddr_llc might not be changed. Zero sllc
before copying to the above layer's structure.

Signed-off-by: Jiri Slaby <jirislaby@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: remove needless (now buggy) & from dev->dev_addr (part2)

Missed part of "&" removal.

Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

llc: fix non-const printk warning

Mark some strings as const.

Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: remove redundant argument comments

Remove redundant argument comments in files of net/*

Signed-off-by: Qinghuang Feng <qhfeng.kernel@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

llc: Use sock_graft() instead of by-hand version.

Signed-off-by: David S. Miller <davem@davemloft.net>

[LLC]: Restrict LLC sockets to root

LLC currently allows users to inject raw frames, including IP packets
encapsulated in SNAP. While Linux doesn't handle IP over SNAP, other
systems do. Restrict LLC sockets to root similar to packet sockets.

[ Modified Patrick's patch to use CAP_NEW_RAW --DaveM ]

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

net: replace remaining __FUNCTION__ occurrences

__FUNCTION__ is gcc-specific, use __func__

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Use helpers to obtain task pid in printks

The task_struct->pid member is going to be deprecated, so start
using the helpers (task_pid_nr/task_pid_vnr/task_pid_nr_ns) in
the kernel.

The first thing to start with is the pid, printed to dmesg - in
this case we may safely use task_pid_nr(). Besides, printks produce
more (much more) than a half of all the explicit pid usage.

[akpm@linux-foundation.org: git-drm went and changed lots of stuff]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

[NET]: Make the device list and device lookups per namespace.

This patch makes most of the generic device layer network
namespace safe. This patch makes dev_base_head a
network namespace variable, and then it picks up
a few associated variables. The functions:
dev_getbyhwaddr
dev_getfirsthwbytype
dev_get_by_flags
dev_get_by_name
__dev_get_by_name
dev_get_by_index
__dev_get_by_index
dev_ioctl
dev_ethtool
dev_load
wireless_process_ioctl

were modified to take a network namespace argument, and
deal with it.

vlan_ioctl_set and brioctl_set were modified so their
hooks will receive a network namespace argument.

So basically anthing in the core of the network stack that was
affected to by the change of dev_base was modified to handle
multiple network namespaces. The rest of the network stack was
simply modified to explicitly use &init_net the initial network
namespace. This can be fixed when those components of the network
stack are modified to handle multiple network namespaces.

For now the ifindex generator is left global.

Fundametally ifindex numbers are per namespace, or else
we will have corner case problems with migration when
we get that far.

At the same time there are assumptions in the network stack
that the ifindex of a network device won't change. Making
the ifindex number global seems a good compromise until
the network stack can cope with ifindex changes when
you change namespaces, and the like.

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Make socket creation namespace safe.

This patch passes in the namespace a new socket should be created in
and has the socket code do the appropriate reference counting. By
virtue of this all socket create methods are touched. In addition
the socket create methods are modified so that they will fail if
you attempt to create a socket in a non-default network namespace.

Failing if we attempt to create a socket outside of the default
network namespace ensures that as we incrementally make the network stack
network namespace aware we will not export functionality that someone
has not audited and made certain is network namespace safe.
Allowing us to partially enable network namespaces before all of the
exotic protocols are supported.

Any protocol layers I have missed will fail to compile because I now
pass an extra parameter into the socket creation code.

[ Integrated AF_IUCV build fixes from Andrew Morton... -DaveM ]

Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Fix occurrences of "the the "

Signed-off-by: Michael Opdenacker <michael@free-electrons.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>

[NET] LLC: Fix whitespace errors.

Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

[LLC]: anotations

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

[LLX]: SOCK_DGRAM interface fixes

The datagram interface of LLC is broken in a couple of ways.
These were discovered when trying to use it to build an out-of-kernel
version of STP.

First it didn't pass the source address of the received packet
in recvfrom(). It needs to copy the source address of received LLC packets
into the socket control block. At the same time fix a security issue
because there was uninitialized data leakage. Every recvfrom call
was just copying out old data.

Second, LLC should not merge multiple packets in one receive call
on datagram sockets. LLC should preserve packet boundaries on
SOCK_DGRAM.

This fix goes against the old historical comments about UNIX98 semantics
but without this fix SOCK_DGRAM is broken and useless. So either ANK's
interpretation was incorect or UNIX98 standard was wrong.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Acked-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Remove obsolete #include <linux/config.h>

Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de>
Signed-off-by: Adrian Bunk <bunk@stusta.de>

[LLC]: allow datagram recvmsg

LLC receive is broken for SOCK_DGRAM.
If an application does recv() on a datagram socket and there
is no data present, don't return "not connected". Instead, just
do normal datagram semantics.

Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

[I/OAT]: Make sk_eat_skb I/OAT aware.

Add an extra argument to sk_eat_skb, and make it move early copied
packets to the async_wait_queue instead of freeing them.

Signed-off-by: Chris Leech <christopher.leech@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[LLC]: Fix sap refcounting

Thanks to Leslie Harlley Watter <leslie@watter.org> for reporting the
problem an testing this patch.

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[LLC]: Replace __inline__ with inline

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[LLC]: Fix struct proto .name

Cut'n'paste error from ddp_proto.

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Add a dev_ioctl() fallback to sock_ioctl()

Currently all network protocols need to call dev_ioctl as the default
fallback in their ioctl implementations. This patch adds a fallback
to dev_ioctl to sock_ioctl if the protocol returned -ENOIOCTLCMD.
This way all the procotol ioctl handlers can be simplified and we don't
need to export dev_ioctl.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: move struct proto_ops to const

I noticed that some of 'struct proto_ops' used in the kernel may share
a cache line used by locks or other heavily modified data. (default
linker alignement is 32 bytes, and L1_CACHE_LINE is 64 or 128 at
least)

This patch makes sure a 'struct proto_ops' can be declared as const,
so that all cpus can share all parts of it without false sharing.

This is not mandatory : a driver can still use a read/write structure
if it needs to (and eventually a __read_mostly)

I made a global stubstitute to change all existing occurences to make
them const.

This should reduce the possibility of false sharing on SMP, and
speedup some socket system calls.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Avoid atomic xchg() for non-error case

It also looks like there were 2 places where the test on sk_err was
missing from the event wait logic (in sk_stream_wait_connect and
sk_stream_wait_memory), while the rest of the sock_error() users look
to be doing the right thing. This version of the patch fixes those,
and cleans up a few places that were testing ->sk_err directly.

Signed-off-by: Benjamin LaHaise <benjamin.c.lahaise@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[LLC]: Make core block on remote busy.

Signed-off-by: Jochen Friedrich <jochen@scram.de>
Acked-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

[LLC]: fix llc_ui_recvmsg, making it behave like tcp_recvmsg

In fact it is an exact copy of the parts that makes sense to LLC :-)

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[LLC]: Fix sparse warnings

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[LLC]: Fix for Bugzilla ticket #5157

Signed-off-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[LLC]: Fix for Bugzilla ticket #5156

Signed-off-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[LLC]: Use refcounting with struct llc_sap

Signed-off-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[LLC]: Do better struct sock accounting on skbs

Signed-off-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[LLC]: Use sk_wait_data

Signed-off-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[LLC]: Use some more likely/unlikely

Signed-off-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[LLC]: Add sysctl support for the LLC timeouts

Signed-off-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[LLC]: Use the sk_wait_event primitive

Signed-off-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[LLC]: Convert llc_ui_wait_for_ functions to use prepare_to_wait/finish_wait

And make it look more like the similar routines in the TCP/IP source code.

Signed-off-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[LLC]: Help the compiler with likely/unlikely, saving some more bytes

Signed-off-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[LLC]: Update comments for llc_ui_bind and llc_ui_autobind to match new behaviour

Signed-off-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[LLC]: Remove unneeded temp net_device variables

Signed-off-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>

[TCP]: Move the tcp sock states to net/tcp_states.h

Lots of places just needs the states, not even linux/tcp.h, where this
enum was, needs it.

This speeds up development of the refactorings as less sources are
rebuilt when things get moved from net/tcp.h.

Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

[NET]: Kill skb->list

Remove the "list" member of struct sk_buff, as it is entirely
redundant. All SKB list removal callers know which list the
SKB is on, so storing this in sk_buff does nothing other than
taking up some space.

Two tricky bits were SCTP, which I took care of, and two ATM
drivers which Francois Romieu <romieu@fr.zoreil.com> fixed
up.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>

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!