This is a note to let you know that I've just added the patch titled
target/iscsi: avoid NULL dereference in CHAP auth error path
to the 4.9-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:
target-iscsi-avoid-null-dereference-in-chap-auth-error-path.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From ce512d79d0466a604793addb6b769d12ee326822 Mon Sep 17 00:00:00 2001
From: David Disseldorp <ddiss@xxxxxxx>
Date: Wed, 13 Dec 2017 18:22:30 +0100
Subject: target/iscsi: avoid NULL dereference in CHAP auth error path
From: David Disseldorp <ddiss@xxxxxxx>
commit ce512d79d0466a604793addb6b769d12ee326822 upstream.
If chap_server_compute_md5() fails early, e.g. via CHAP_N mismatch, then
crypto_free_shash() is called with a NULL pointer which gets
dereferenced in crypto_shash_tfm().
Fixes: 69110e3cedbb ("iscsi-target: Use shash and ahash")
Suggested-by: Markus Elfring <elfring@xxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: David Disseldorp <ddiss@xxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # 4.6+
Signed-off-by: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/target/iscsi/iscsi_target_auth.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/target/iscsi/iscsi_target_auth.c
+++ b/drivers/target/iscsi/iscsi_target_auth.c
@@ -413,7 +413,8 @@ static int chap_server_compute_md5(
auth_ret = 0;
out:
kzfree(desc);
- crypto_free_shash(tfm);
+ if (tfm)
+ crypto_free_shash(tfm);
kfree(challenge);
kfree(challenge_binhex);
return auth_ret;
Patches currently in stable-queue which might be from ddiss@xxxxxxx are
queue-4.9/target-iscsi-avoid-null-dereference-in-chap-auth-error-path.patch