Commit fb2b2a1d authored by Tetsuo Handa's avatar Tetsuo Handa Committed by Linus Torvalds
Browse files

CRED: Fix memory and refcount leaks upon security_prepare_creds() failure



In prepare_kernel_cred() since 2.6.29, put_cred(new) is called without
assigning new->usage when security_prepare_creds() returned an error.  As a
result, memory for new and refcount for new->{user,group_info,tgcred} are
leaked because put_cred(new) won't call __put_cred() unless old->usage == 1.

Fix these leaks by assigning new->usage (and new->subscribers which was added
in 2.6.32) before calling security_prepare_creds().
Signed-off-by: default avatarTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: default avatarDavid Howells <dhowells@redhat.com>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 2edeaa34
......@@ -657,6 +657,8 @@ struct cred *prepare_kernel_cred(struct task_struct *daemon)
validate_creds(old);
*new = *old;
atomic_set(&new->usage, 1);
set_cred_subscribers(new, 0);
get_uid(new->user);
get_group_info(new->group_info);
......@@ -674,8 +676,6 @@ struct cred *prepare_kernel_cred(struct task_struct *daemon)
if (security_prepare_creds(new, old, GFP_KERNEL) < 0)
goto error;
atomic_set(&new->usage, 1);
set_cred_subscribers(new, 0);
put_cred(old);
validate_creds(new);
return new;
......
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