[PATCH] Error during attempt to join key management session can leave semaphore pinned
authorDavid Howells <dhowells@redhat.com>
Thu, 4 Aug 2005 20:07:06 +0000 (13:07 -0700)
committerLinus Torvalds <torvalds@g5.osdl.org>
Thu, 4 Aug 2005 20:11:14 +0000 (13:11 -0700)
commitbcf945d36fa0598f41ac4ad46a9dc43135460263
tree7a2aa188442bf863f20055a001baf85143d7a5b9
parent6fb0caa42308923d9e4ed7b36ec077b97c107e24
[PATCH] Error during attempt to join key management session can leave semaphore pinned

The attached patch prevents an error during the key session joining operation
from hanging future joins in the D state [CAN-2005-2098].

The problem is that the error handling path for the KEYCTL_JOIN_SESSION_KEYRING
operation has one error path that doesn't release the session management
semaphore. Further attempts to get the semaphore will then sleep for ever in
the D state.

This can happen in four situations, all involving an attempt to allocate a new
session keyring:

 (1) ENOMEM.

 (2) The users key quota being reached.

 (3) A keyring name that is an empty string.

 (4) A keyring name that is too long.

Any user may attempt this operation, and so any user can cause the problem to
occur.

Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
security/keys/process_keys.c