WSL2-Linux-Kernel/ipc
Cong Wang f991af3daa mqueue: fix a use-after-free in sys_mq_notify()
The retry logic for netlink_attachskb() inside sys_mq_notify()
is nasty and vulnerable:

1) The sock refcnt is already released when retry is needed
2) The fd is controllable by user-space because we already
   release the file refcnt

so we when retry but the fd has been just closed by user-space
during this small window, we end up calling netlink_detachskb()
on the error path which releases the sock again, later when
the user-space closes this socket a use-after-free could be
triggered.

Setting 'sock' to NULL here should be sufficient to fix it.

Reported-by: GeneBlue <geneblue.mail@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-07-09 14:37:19 -07:00
..
Makefile mqueue: move compat syscalls to native ones 2017-07-04 13:13:49 -04:00
compat.c
ipc_sysctl.c
mq_sysctl.c
mqueue.c mqueue: fix a use-after-free in sys_mq_notify() 2017-07-09 14:37:19 -07:00
msg.c
msgutil.c
namespace.c
sem.c
shm.c fs: remove call_fsync helper function 2017-07-05 18:44:23 -04:00
syscall.c
util.c mm: introduce kv[mz]alloc helpers 2017-05-08 17:15:12 -07:00
util.h ipc: Remove unused declaration of recompute_msgmni 2017-04-17 21:53:07 -05:00