This is a note to let you know that I've just added the patch titled iscsi-target: Reject mutual authentication with reflected CHAP_C to the 3.14-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: iscsi-target-reject-mutual-authentication-with-reflected-chap_c.patch and it can be found in the queue-3.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 1d2b60a5545942b1376cb48c1d55843d71e3a08f Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx> Date: Thu, 5 Jun 2014 18:08:57 -0700 Subject: iscsi-target: Reject mutual authentication with reflected CHAP_C From: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx> commit 1d2b60a5545942b1376cb48c1d55843d71e3a08f upstream. This patch adds an explicit check in chap_server_compute_md5() to ensure the CHAP_C value received from the initiator during mutual authentication does not match the original CHAP_C provided by the target. This is in line with RFC-3720, section 8.2.1: Originators MUST NOT reuse the CHAP challenge sent by the Responder for the other direction of a bidirectional authentication. Responders MUST check for this condition and close the iSCSI TCP connection if it occurs. Reported-by: Tejas Vaykole <tejas.vaykole@xxxxxxxxxxxxxx> Signed-off-by: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/target/iscsi/iscsi_target_auth.c | 10 ++++++++++ 1 file changed, 10 insertions(+) --- a/drivers/target/iscsi/iscsi_target_auth.c +++ b/drivers/target/iscsi/iscsi_target_auth.c @@ -314,6 +314,16 @@ static int chap_server_compute_md5( goto out; } /* + * During mutual authentication, the CHAP_C generated by the + * initiator must not match the original CHAP_C generated by + * the target. + */ + if (!memcmp(challenge_binhex, chap->challenge, CHAP_CHALLENGE_LENGTH)) { + pr_err("initiator CHAP_C matches target CHAP_C, failing" + " login attempt\n"); + goto out; + } + /* * Generate CHAP_N and CHAP_R for mutual authentication. */ tfm = crypto_alloc_hash("md5", 0, CRYPTO_ALG_ASYNC); Patches currently in stable-queue which might be from nab@xxxxxxxxxxxxxxx are queue-3.14/target-fix-null-pointer-dereference-for-xcopy-in-target_put_sess_cmd.patch queue-3.14/iscsi-target-reject-mutual-authentication-with-reflected-chap_c.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html