From: Ondrej Mosnacek omosnace@redhat.com
[ 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@redhat.com Reviewed-by: Jeff Moyer jmoyer@redhat.com Link: https://lore.kernel.org/r/20230718115607.65652-1-omosnace@redhat.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- io_uring/io_uring.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index d6667b435dd39..685cf14a7189e 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -3859,7 +3859,7 @@ static __cold int io_uring_create(unsigned entries, struct io_uring_params *p, ctx->syscall_iopoll = 1;
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());
/*