From mboxrd@z Thu Jan 1 00:00:00 1970 From: tytso@mit.edu (Theodore Ts'o) Date: Sun, 29 Oct 2017 06:23:05 -0400 Subject: [PATCH v2] fscrypt: fix dereference of NULL user_key_payload In-Reply-To: <20171009194618.67494-1-ebiggers3@gmail.com> References: <20171009194618.67494-1-ebiggers3@gmail.com> Message-ID: <20171029102305.4ifapjehlrgwsqmu@thunk.org> To: linux-security-module@vger.kernel.org List-Id: linux-security-module.vger.kernel.org On Mon, Oct 09, 2017 at 12:46:18PM -0700, Eric Biggers wrote: > From: Eric Biggers > > When an fscrypt-encrypted file is opened, we request the file's master > key from the keyrings service as a logon key, then access 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: 88bd6ccdcdd6 ("ext4 crypto: add encryption key management facilities") > Reviewed-by: James Morris > Cc: [v4.1+] > Signed-off-by: Eric Biggers Applied, thanks. - Ted -- To unsubscribe from this list: send the line "unsubscribe linux-security-module" in the body of a message to majordomo at vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html