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.
Fixes: 15bc01effefe ("ucounts: Fix signal ucount refcounting")
Tested-by: Roman Gushchin <roman.gushchin@xxxxxxxxx>
Co-debugged-by: Roman Gushchin <roman.gushchin@xxxxxxxxx>
Cc: Kees Cook <kees@xxxxxxxxxx>
Cc: Andrei Vagin <avagin@xxxxxxxxxx>
Cc: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
Cc: Alexey Gladkov <legion@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Andrei Vagin <avagin@xxxxxxxxxx>
---
kernel/ucount.c | 5 ++---
1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/kernel/ucount.c b/kernel/ucount.c
index 8c07714ff27d..16c0ea1cb432 100644
--- a/kernel/ucount.c
+++ b/kernel/ucount.c
@@ -328,13 +328,12 @@ long inc_rlimit_get_ucounts(struct ucounts *ucounts, enum rlimit_type type)
if (new != 1)
continue;
if (!get_ucounts(iter))
- goto dec_unwind;
+ goto unwind;
}
return ret;
-dec_unwind:
+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;
}
--
2.47.0.163.g1226f6d8fa-goog
