This is a note to let you know that I've just added the patch titled kcm: fix a null pointer dereference in kcm_sendmsg() 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: kcm-fix-a-null-pointer-dereference-in-kcm_sendmsg.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 foo@baz Thu Feb 23 21:13:05 CET 2017 From: WANG Cong <xiyou.wangcong@xxxxxxxxx> Date: Mon, 13 Feb 2017 11:13:16 -0800 Subject: kcm: fix a null pointer dereference in kcm_sendmsg() From: WANG Cong <xiyou.wangcong@xxxxxxxxx> [ Upstream commit cd27b96bc13841ee7af25837a6ae86fee87273d6 ] In commit 98e3862ca2b1 ("kcm: fix 0-length case for kcm_sendmsg()") I tried to avoid skb allocation for 0-length case, but missed a check for NULL pointer in the non EOR case. Fixes: 98e3862ca2b1 ("kcm: fix 0-length case for kcm_sendmsg()") Reported-by: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: Tom Herbert <tom@xxxxxxxxxxxxxxx> Signed-off-by: Cong Wang <xiyou.wangcong@xxxxxxxxx> Acked-by: Tom Herbert <tom@xxxxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/kcm/kcmsock.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/net/kcm/kcmsock.c +++ b/net/kcm/kcmsock.c @@ -1044,8 +1044,10 @@ wait_for_memory: } else { /* Message not complete, save state */ partial_message: - kcm->seq_skb = head; - kcm_tx_msg(head)->last_skb = skb; + if (head) { + kcm->seq_skb = head; + kcm_tx_msg(head)->last_skb = skb; + } } KCM_STATS_ADD(kcm->stats.tx_bytes, copied); Patches currently in stable-queue which might be from xiyou.wangcong@xxxxxxxxx are queue-4.9/kcm-fix-0-length-case-for-kcm_sendmsg.patch queue-4.9/kcm-fix-a-null-pointer-dereference-in-kcm_sendmsg.patch