Patch "bnxt_en: Fix NULL pointer dereference in reopen failure path" has been added to the 4.4-stable tree

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

bnxt_en: Fix NULL pointer dereference in reopen failure path

to the 4.4-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:
bnxt_en-fix-null-pointer-dereference-in-reopen-failure-path.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Sankar Patchineelam <[email protected]>
Date: Tue, 28 Mar 2017 19:47:29 -0400
Subject: bnxt_en: Fix NULL pointer dereference in reopen failure path

From: Sankar Patchineelam <[email protected]>

[ Upstream commit 2247925f0942dc4e7c09b1cde45ca18461d94c5f ]

Net device reset can fail when the h/w or f/w is in a bad state. Subsequent netdevice open fails in bnxt_hwrm_stat_ctx_alloc(). The cleanup invokes bnxt_hwrm_resource_free() which inturn calls bnxt_disable_int(). In this routine, the code segment

if (ring->fw_ring_id != INVALID_HW_RING_ID)
BNXT_CP_DB(cpr->cp_doorbell, cpr->cp_raw_cons);

results in NULL pointer dereference as cpr->cp_doorbell is not yet initialized, and fw_ring_id is zero.

The fix is to initialize cpr fw_ring_id to INVALID_HW_RING_ID before bnxt_init_chip() is invoked.

---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c |   13 +++++++++++++
 1 file changed, 13 insertions(+)

@@ -2014,6 +2014,18 @@ static int bnxt_init_one_rx_ring(struct
 	return 0;
 }
 
+static void bnxt_init_cp_rings(struct bnxt *bp)
+{
+	int i;
+
+	for (i = 0; i < bp->cp_nr_rings; i++) {
+		struct bnxt_cp_ring_info *cpr = &bp->bnapi[i]->cp_ring;
+		struct bnxt_ring_struct *ring = &cpr->cp_ring_struct;
+
+		ring->fw_ring_id = INVALID_HW_RING_ID;
+	}
+}
+
 static int bnxt_init_rx_rings(struct bnxt *bp)
 {
 	int i, rc = 0;

@@ -3977,6 +3989,7 @@ static int bnxt_shutdown_nic(struct bnxt
 
 static int bnxt_init_nic(struct bnxt *bp, bool irq_re_init)
 {
+	bnxt_init_cp_rings(bp);
 	bnxt_init_rx_rings(bp);
 	bnxt_init_tx_rings(bp);
 	bnxt_init_ring_grps(bp, irq_re_init);

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

queue-4.4/bnxt_en-fix-null-pointer-dereference-in-reopen-failure-path.patch