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| author | Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> | 2011-02-07 13:36:16 +0000 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-02-07 14:04:00 -0800 |
| commit | fb2b2a1d37f80cc818fd4487b510f4e11816e5e1 (patch) | |
| tree | 00a16a9440fb1d522160a404c97ed327f77a92a1 /kernel/cred.c | |
| parent | 2edeaa34a6e3f2c43b667f6c4f7b27944b811695 (diff) | |
| download | lwn-fb2b2a1d37f80cc818fd4487b510f4e11816e5e1.tar.gz lwn-fb2b2a1d37f80cc818fd4487b510f4e11816e5e1.zip | |
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: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'kernel/cred.c')
| -rw-r--r-- | kernel/cred.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/kernel/cred.c b/kernel/cred.c index fcf104bb5aa9..3a9d6dd53a6c 100644 --- a/kernel/cred.c +++ b/kernel/cred.c @@ -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; |