[dpdk-stable] patch 'net: fix underflow for checksum of invalid IPv4 packets' has been queued to LTS release 18.11.1

[Kevin Traynor]

Hi,

FYI, your patch has been queued to LTS release 18.11.1

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 01/11/19. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the
patch applied to the branch. This will indicate if there was any rebasing
needed to apply to the stable branch. If there were code changes for rebasing
(ie: not only metadata diffs), please double check that the rebase was
correctly done.

Thanks.

Kevin Traynor

---
>From d9d904fabe373e75ac360c4450bbcdf0bd41c365 Mon Sep 17 00:00:00 2001
From: Bruce Richardson <bruce.richardson at intel.com>
Date: Mon, 17 Dec 2018 15:50:04 +0000
Subject: [PATCH] net: fix underflow for checksum of invalid IPv4 packets

[ upstream commit 8743d499a59c3d6a7c743861fd3baf06ed5fe763 ]

If we receive a packet with an invalid IP header, where the total packet
length is reported as less than the IP header length, we would end up
getting an underflow in the length subtraction.

This could cause us to checksum e.g. 4GB of data in the case where the
result of the subtraction was -1.

We fix this by having the function return 0 - an invalid sum - when
the length is less than the header length.

Fixes: af75078fece3 ("first public release")
Fixes: 6006818cfb26 ("net: new checksum functions")

Signed-off-by: Bruce Richardson <bruce.richardson at intel.com>
Acked-by: Hemant Agrawal <hemant.agrawal at nxp.com>
---
 lib/librte_net/rte_ip.h | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/lib/librte_net/rte_ip.h b/lib/librte_net/rte_ip.h
index f2a8904a2..f9b909090 100644
--- a/lib/librte_net/rte_ip.h
+++ b/lib/librte_net/rte_ip.h
@@ -311,5 +311,6 @@ rte_ipv4_phdr_cksum(const struct ipv4_hdr *ipv4_hdr, uint64_t ol_flags)
  *   The pointer to the beginning of the L4 header.
  * @return
- *   The complemented checksum to set in the IP packet.
+ *   The complemented checksum to set in the IP packet
+ *   or 0 on error
  */
 static inline uint16_t
@@ -317,8 +318,11 @@ rte_ipv4_udptcp_cksum(const struct ipv4_hdr *ipv4_hdr, const void *l4_hdr)
 {
 	uint32_t cksum;
-	uint32_t l4_len;
+	uint32_t l3_len, l4_len;
 
-	l4_len = (uint32_t)(rte_be_to_cpu_16(ipv4_hdr->total_length) -
-		sizeof(struct ipv4_hdr));
+	l3_len = rte_be_to_cpu_16(ipv4_hdr->total_length);
+	if (l3_len < sizeof(struct ipv4_hdr))
+		return 0;
+
+	l4_len = l3_len - sizeof(struct ipv4_hdr);
 
 	cksum = rte_raw_cksum(l4_hdr, l4_len);
-- 
2.19.0

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2019-01-04 13:23:08.958542188 +0000
+++ 0062-net-fix-underflow-for-checksum-of-invalid-IPv4-packe.patch	2019-01-04 13:23:07.000000000 +0000
@@ -1,8 +1,10 @@
-From 8743d499a59c3d6a7c743861fd3baf06ed5fe763 Mon Sep 17 00:00:00 2001
+From d9d904fabe373e75ac360c4450bbcdf0bd41c365 Mon Sep 17 00:00:00 2001
 From: Bruce Richardson <bruce.richardson at intel.com>
 Date: Mon, 17 Dec 2018 15:50:04 +0000
 Subject: [PATCH] net: fix underflow for checksum of invalid IPv4 packets
 
+[ upstream commit 8743d499a59c3d6a7c743861fd3baf06ed5fe763 ]
+
 If we receive a packet with an invalid IP header, where the total packet
 length is reported as less than the IP header length, we would end up
 getting an underflow in the length subtraction.
@@ -15,7 +17,6 @@
 
 Fixes: af75078fece3 ("first public release")
 Fixes: 6006818cfb26 ("net: new checksum functions")
-Cc: stable at dpdk.org
 
 Signed-off-by: Bruce Richardson <bruce.richardson at intel.com>
 Acked-by: Hemant Agrawal <hemant.agrawal at nxp.com>