watch_queue: Actually free the watch
[ Upstream commit
3d8dcf278b1ee1eff1e90be848fa2237db4c07a7 ]
free_watch() does everything barring actually freeing the watch object. Fix
this by adding the missing kfree.
kmemleak produces a report something like the following. Note that as an
address can be seen in the first word, the watch would appear to have gone
through call_rcu().
BUG: memory leak
unreferenced object 0xffff88810ce4a200 (size 96):
comm "syz-executor352", pid 3605, jiffies
4294947473 (age 13.720s)
hex dump (first 32 bytes):
e0 82 48 0d 81 88 ff ff 00 00 00 00 00 00 00 00 ..H.............
80 a2 e4 0c 81 88 ff ff 00 00 00 00 00 00 00 00 ................
backtrace:
[<
ffffffff8214e6cc>] kmalloc include/linux/slab.h:581 [inline]
[<
ffffffff8214e6cc>] kzalloc include/linux/slab.h:714 [inline]
[<
ffffffff8214e6cc>] keyctl_watch_key+0xec/0x2e0 security/keys/keyctl.c:1800
[<
ffffffff8214ec84>] __do_sys_keyctl+0x3c4/0x490 security/keys/keyctl.c:2016
[<
ffffffff84493a25>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<
ffffffff84493a25>] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
[<
ffffffff84600068>] entry_SYSCALL_64_after_hwframe+0x44/0xae
Fixes:
c73be61cede5 ("pipe: Add general notification queue support")
Reported-and-tested-by: syzbot+6e2de48f06cdb2884bfc@syzkaller.appspotmail.com
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>