This is a note to let you know that I've just added the patch titled
io_uring: don't audit the capability check in io_uring_create()
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
io_uring-don-t-audit-the-capability-check-in-io_urin.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 4b74f1cbdf97d18a5afa9ae0bcae7b211dbc1e02
Author: Ondrej Mosnacek <omosnace@xxxxxxxxxx>
Date: Tue Jul 18 13:56:07 2023 +0200
io_uring: don't audit the capability check in io_uring_create()
[ Upstream commit 6adc2272aaaf84f34b652cf77f770c6fcc4b8336 ]
The check being unconditional may lead to unwanted denials reported by
LSMs when a process has the capability granted by DAC, but denied by an
LSM. In the case of SELinux such denials are a problem, since they can't
be effectively filtered out via the policy and when not silenced, they
produce noise that may hide a true problem or an attack.
Since not having the capability merely means that the created io_uring
context will be accounted against the current user's RLIMIT_MEMLOCK
limit, we can disable auditing of denials for this check by using
ns_capable_noaudit() instead of capable().
Fixes: 2b188cc1bb85 ("Add io_uring IO interface")
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2193317
Signed-off-by: Ondrej Mosnacek <omosnace@xxxxxxxxxx>
Reviewed-by: Jeff Moyer <jmoyer@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20230718115607.65652-1-omosnace@xxxxxxxxxx
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index d7f87157be9aa..f65c6811ede81 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -10602,7 +10602,7 @@ static int io_uring_create(unsigned entries, struct io_uring_params *p,
if (!ctx)
return -ENOMEM;
ctx->compat = in_compat_syscall();
- if (!capable(CAP_IPC_LOCK))
+ if (!ns_capable_noaudit(&init_user_ns, CAP_IPC_LOCK))
ctx->user = get_uid(current_user());
/*
