Patch "Don't leak a key reference if request_key() tries to use a revoked keyring" has been added to the 3.18-stable tree

Patch "Don't leak a key reference if request_key() tries to use a revoked keyring" has been added to the 3.18-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    Don't leak a key reference if request_key() tries to use a revoked keyring

to the 3.18-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     don-t-leak-a-key-reference-if-request_key-tries-to-use-a-revoked-keyring.patch
and it can be found in the queue-3.18 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From d0709f1e66e8066c4ac6a54620ec116aa41937c0 Mon Sep 17 00:00:00 2001
From: David Jeffery <djeffery@redhat.com>
Date: Thu, 12 Feb 2015 16:45:31 +0000
Subject: Don't leak a key reference if request_key() tries to use a revoked keyring

From: David Jeffery <djeffery@redhat.com>

commit d0709f1e66e8066c4ac6a54620ec116aa41937c0 upstream.

If a request_key() call to allocate and fill out a key attempts to insert the
key structure into a revoked keyring, the key will leak, using memory and part
of the user's key quota until the system reboots. This is from a failure of
construct_alloc_key() to decrement the key's reference count after the attempt
to insert into the requested keyring is rejected.

key_put() needs to be called in the link_prealloc_failed callpath to ensure
the unused key is released.

Signed-off-by: David Jeffery <djeffery@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 security/keys/request_key.c |    1 +
 1 file changed, 1 insertion(+)

--- a/security/keys/request_key.c
+++ b/security/keys/request_key.c
@@ -437,6 +437,7 @@ link_check_failed:
 
 link_prealloc_failed:
 	mutex_unlock(&user->cons_lock);
+	key_put(key);
 	kleave(" = %d [prelink]", ret);
 	return ret;
 


Patches currently in stable-queue which might be from djeffery@redhat.com are

queue-3.18/don-t-leak-a-key-reference-if-request_key-tries-to-use-a-revoked-keyring.patch