Patch "RDMA/iw_cxgb4: Avoid touch after free error in ARP failure handlers" has been added to the 4.9-stable tree

This is a note to let you know that I've just added the patch titled

RDMA/iw_cxgb4: Avoid touch after free error in ARP failure handlers

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:
rdma-iw_cxgb4-avoid-touch-after-free-error-in-arp-failure-handlers.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 <[email protected]> know about it.

From: Raju Rangoju <[email protected]>
Date: Mon, 15 May 2017 06:40:39 +0000
Subject: RDMA/iw_cxgb4: Avoid touch after free error in ARP failure handlers

From: Raju Rangoju <[email protected]>

[ Upstream commit 1dad0ebeea1cd890b8892523f736916e245b0aef ]

The patch 761e19a504af (RDMA/iw_cxgb4: Handle return value of c4iw_ofld_send() in abort_arp_failure()) from May 6, 2016 leads to the following static checker warning:
drivers/infiniband/hw/cxgb4/cm.c:575 abort_arp_failure()
warn: passing freed memory 'skb'

Also fixes skb leak when l2t resolution fails

c4iw_ofld_send() in abort_arp_failure())

---
 drivers/infiniband/hw/cxgb4/cm.c |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

@@ -488,6 +488,7 @@ static int _put_ep_safe(struct c4iw_dev
 
 	ep = *((struct c4iw_ep **)(skb->cb + 2 * sizeof(void *)));
 	release_ep_resources(ep);
+	kfree_skb(skb);
 	return 0;
 }
 

@@ -498,6 +499,7 @@ static int _put_pass_ep_safe(struct c4iw
 	ep = *((struct c4iw_ep **)(skb->cb + 2 * sizeof(void *)));
 	c4iw_put_ep(&ep->parent_ep->com);
 	release_ep_resources(ep);
+	kfree_skb(skb);
 	return 0;
 }
 

@@ -569,11 +571,13 @@ static void abort_arp_failure(void *hand
 
 	PDBG("%s rdev %p\n", __func__, rdev);
 	req->cmd = CPL_ABORT_NO_RST;
+	skb_get(skb);
 	ret = c4iw_ofld_send(rdev, skb);
 	if (ret) {
 		__state_set(&ep->com, DEAD);
 		queue_arp_failure_cpl(ep, skb, FAKE_CPL_PUT_EP_SAFE);
-	}
+	} else
+		kfree_skb(skb);
 }
 
 static int send_flowc(struct c4iw_ep *ep)

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/rdma-iw_cxgb4-avoid-touch-after-free-error-in-arp-failure-handlers.patch