Home
last modified time | relevance | path

Searched hist:"192 cabd6" (Results 1 – 1 of 1) sorted by path

/linux/lib/
H A Ddigsig.c192cabd6 Mon Oct 09 19:43:20 GMT 2017 Eric Biggers <ebiggers@google.com> lib/digsig: fix dereference of NULL user_key_payload

digsig_verify() requests a user key, then accesses its payload.
However, a revoked key has a NULL payload, and we failed to check for
this. request_key() *does* skip revoked keys, but there is still a
window where the key can be revoked before we acquire its semaphore.

Fix it by checking for a NULL payload, treating it like a key which was
already revoked at the time it was requested.

Fixes: 051dbb918c7f ("crypto: digital signature verification support")
Reviewed-by: James Morris <james.l.morris@oracle.com>
Cc: <stable@vger.kernel.org> [v3.3+]
Cc: Dmitry Kasatkin <dmitry.kasatkin@intel.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>