The patch titled Subject: ucounts: fix counter leak in inc_rlimit_get_ucounts() has been added to the -mm mm-hotfixes-unstable branch. Its filename is ucounts-fix-counter-leak-in-inc_rlimit_get_ucounts.patch

This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...

This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------ From: Andrei Vagin avagin@google.com Subject: ucounts: fix counter leak in inc_rlimit_get_ucounts() Date: Fri, 1 Nov 2024 19:19:40 +0000

The inc_rlimit_get_ucounts() increments the specified rlimit counter and then checks its limit. If the value exceeds the limit, the function returns an error without decrementing the counter.

Link: https://lkml.kernel.org/r/20241101191940.3211128-1-roman.gushchin@linux.dev Fixes: 15bc01effefe ("ucounts: Fix signal ucount refcounting") Signed-off-by: Andrei Vagin avagin@google.com Co-developed-by: Roman Gushchin roman.gushchin@linux.dev Signed-off-by: Roman Gushchin roman.gushchin@linux.dev Tested-by: Roman Gushchin roman.gushchin@linux.dev Acked-by: Alexey Gladkov legion@kernel.org Cc: Kees Cook kees@kernel.org Cc: Andrei Vagin avagin@google.com Cc: "Eric W. Biederman" ebiederm@xmission.com Cc: Alexey Gladkov legion@kernel.org Cc: Oleg Nesterov oleg@redhat.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---

kernel/ucount.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)

--- a/kernel/ucount.c~ucounts-fix-counter-leak-in-inc_rlimit_get_ucounts +++ a/kernel/ucount.c @@ -318,7 +318,7 @@ long inc_rlimit_get_ucounts(struct ucoun for (iter = ucounts; iter; iter = iter->ns->ucounts) { long new = atomic_long_add_return(1, &iter->rlimit[type]); if (new < 0 || (!override_rlimit && (new > max))) - goto unwind; + goto dec_unwind; if (iter == ucounts) ret = new; max = get_userns_rlimit_max(iter->ns, type); @@ -335,7 +335,6 @@ long inc_rlimit_get_ucounts(struct ucoun dec_unwind: dec = atomic_long_sub_return(1, &iter->rlimit[type]); WARN_ON_ONCE(dec < 0); -unwind: do_dec_rlimit_put_ucounts(ucounts, iter, type); return 0; } _

Patches currently in -mm which might be from avagin@google.com are

ucounts-fix-counter-leak-in-inc_rlimit_get_ucounts.patch