From: Eric W. Biederman <ebiederm@xxxxxxxxxxxx> commit 34dc2fd6e6908499b669c7b45320cddf38b332e1 upstream. Instead of leaking the ucounts in new if alloc_ucounts fails, store the result of alloc_ucounts into a temporary variable, which is later assigned to new->ucounts. Cc: stable@xxxxxxxxxxxxxxx Fixes: 905ae01c4ae2 ("Add a reference to ucounts for each cred") Link: https://lkml.kernel.org/r/87pms2s0v8.fsf_-_@disp2133 Tested-by: Yu Zhao <yuzhao@xxxxxxxxxx> Reviewed-by: Alexey Gladkov <legion@xxxxxxxxxx> Signed-off-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- kernel/cred.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/kernel/cred.c +++ b/kernel/cred.c @@ -667,7 +667,7 @@ int set_cred_ucounts(struct cred *new) { struct task_struct *task = current; const struct cred *old = task->real_cred; - struct ucounts *old_ucounts = new->ucounts; + struct ucounts *new_ucounts, *old_ucounts = new->ucounts; if (new->user == old->user && new->user_ns == old->user_ns) return 0; @@ -679,9 +679,10 @@ int set_cred_ucounts(struct cred *new) if (old_ucounts && 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))) + if (!(new_ucounts = alloc_ucounts(new->user_ns, new->euid))) return -EAGAIN; + new->ucounts = new_ucounts; if (old_ucounts) put_ucounts(old_ucounts);