| commit | a3a8784454692dd72e5d5d34dcdab17b4420e74c | |
| author | Sasha Levin <sasha.levin@oracle.com> | |
| Mon, 29 Dec 2014 14:39:01 +0000 (29 09:39 -0500) | ||
| committer | David Howells <dhowells@redhat.com> | |
| Mon, 5 Jan 2015 15:58:01 +0000 (5 15:58 +0000) | ||
| tree | be2da54315f410323cc2fca04f63da30cbd2147d | treesnapshot (tar.gz zip) |
| parent | 693a30b8f19a964087a3762d09fb2e1cbad6b0d4 | commitdiff |
KEYS: close race between key lookup and freeing
When a key is being garbage collected, it's key->user would get put before
the ->destroy() callback is called, where the key is removed from it's
respective tracking structures.
This leaves a key hanging in a semi-invalid state which leaves a window open
for a different task to try an access key->user. An example is
find_keyring_by_name() which would dereference key->user for a key that is
in the process of being garbage collected (where key->user was freed but
->destroy() wasn't called yet - so it's still present in the linked list).
This would cause either a panic, or corrupt memory.
Fixes CVE-2014-9529.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: David Howells <dhowells@redhat.com>
When a key is being garbage collected, it's key->user would get put before
the ->destroy() callback is called, where the key is removed from it's
respective tracking structures.
This leaves a key hanging in a semi-invalid state which leaves a window open
for a different task to try an access key->user. An example is
find_keyring_by_name() which would dereference key->user for a key that is
in the process of being garbage collected (where key->user was freed but
->destroy() wasn't called yet - so it's still present in the linked list).
This would cause either a panic, or corrupt memory.
Fixes CVE-2014-9529.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: David Howells <dhowells@redhat.com>
| security/keys/gc.c | diffblobblamehistory |