[PATCH 1/4] ucounts: In set_cred_ucounts assume new->ucounts is non-NULL
From: Eric W. Biederman <hidden>
Date: 2021-10-18 17:55:53
Also in:
lkml
Subsystem:
credentials, the rest · Maintainers:
Paul Moore, Linus Torvalds
Any cred that is destined for use by commit_creds must have a non-NULL cred->ucounts field. Only curing credential construction is a NULL cred->ucounts valid. Only abort_creds, put_cred, and put_cred_rcu needs to deal with a cred with a NULL ucount. As set_cred_ucounts is non of those case don't confuse people by handling something that can not happen. Signed-off-by: "Eric W. Biederman" <redacted> --- kernel/cred.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)
diff --git a/kernel/cred.c b/kernel/cred.c
index 1ae0b4948a5a..473d17c431f3 100644
--- a/kernel/cred.c
+++ b/kernel/cred.c@@ -676,15 +676,14 @@ int set_cred_ucounts(struct cred *new) * This optimization is needed because alloc_ucounts() uses locks * for table lookups. */ - if (old_ucounts && old_ucounts->ns == new->user_ns && uid_eq(old_ucounts->uid, new->euid)) + if (old_ucounts->ns == new->user_ns && uid_eq(old_ucounts->uid, new->euid)) return 0; if (!(new_ucounts = alloc_ucounts(new->user_ns, new->euid))) return -EAGAIN; new->ucounts = new_ucounts; - if (old_ucounts) - put_ucounts(old_ucounts); + put_ucounts(old_ucounts); return 0; }
--
2.20.1