From: Michael Chan <michael.chan@broadcom.com>
Date: Fri, 13 Oct 2017 21:09:33 -0400
Subject: bnxt_en: Fix possible corrupted NVRAM parameters from firmware
 response.
Patch-mainline: v4.14-rc6
Git-commit: cc72f3b1feb4fd38d33ab7a013d5ab95041cb8ba
References: bsc#1050242 FATE#322914

In bnxt_find_nvram_item(), it is copying firmware response data after
releasing the mutex.  This can cause the firmware response data
to be corrupted if the next firmware response overwrites the response
buffer.  The rare problem shows up when running ethtool -i repeatedly.

Fix it by calling the new variant _hwrm_send_message_silent() that requires
the caller to take the mutex and to release it after the response data has
been copied.

Fixes: 3ebf6f0a09a2 ("bnxt_en: Add installed-package version reporting via Ethtool GDRVINFO")
Reported-by: Sarveswara Rao Mygapula <sarveswararao.mygapula@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt.c         |    6 ++++++
 drivers/net/ethernet/broadcom/bnxt/bnxt.h         |    1 +
 drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c |    4 +++-
 3 files changed, 10 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c
@@ -3466,6 +3466,12 @@ int _hwrm_send_message(struct bnxt *bp,
 	return bnxt_hwrm_do_send_msg(bp, msg, msg_len, timeout, false);
 }
 
+int _hwrm_send_message_silent(struct bnxt *bp, void *msg, u32 msg_len,
+			      int timeout)
+{
+	return bnxt_hwrm_do_send_msg(bp, msg, msg_len, timeout, true);
+}
+
 int hwrm_send_message(struct bnxt *bp, void *msg, u32 msg_len, int timeout)
 {
 	int rc;
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h
@@ -1362,6 +1362,7 @@ void bnxt_set_ring_params(struct bnxt *)
 int bnxt_set_rx_skb_mode(struct bnxt *bp, bool page_mode);
 void bnxt_hwrm_cmd_hdr_init(struct bnxt *, void *, u16, u16, u16);
 int _hwrm_send_message(struct bnxt *, void *, u32, int);
+int _hwrm_send_message_silent(struct bnxt *bp, void *msg, u32 len, int timeout);
 int hwrm_send_message(struct bnxt *, void *, u32, int);
 int hwrm_send_message_silent(struct bnxt *, void *, u32, int);
 int bnxt_hwrm_func_rgtr_async_events(struct bnxt *bp, unsigned long *bmap,
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
@@ -1809,7 +1809,8 @@ static int bnxt_find_nvram_item(struct n
 	req.dir_ordinal = cpu_to_le16(ordinal);
 	req.dir_ext = cpu_to_le16(ext);
 	req.opt_ordinal = NVM_FIND_DIR_ENTRY_REQ_OPT_ORDINAL_EQ;
-	rc = hwrm_send_message_silent(bp, &req, sizeof(req), HWRM_CMD_TIMEOUT);
+	mutex_lock(&bp->hwrm_cmd_lock);
+	rc = _hwrm_send_message_silent(bp, &req, sizeof(req), HWRM_CMD_TIMEOUT);
 	if (rc == 0) {
 		if (index)
 			*index = le16_to_cpu(output->dir_idx);
@@ -1818,6 +1819,7 @@ static int bnxt_find_nvram_item(struct n
 		if (data_length)
 			*data_length = le32_to_cpu(output->dir_data_length);
 	}
+	mutex_unlock(&bp->hwrm_cmd_lock);
 	return rc;
 }