[lvc-project] [PATCH net] net: qlogic/qede: fix potential out-of-bounds read in qede_tpa_cont() and qede_tpa_end()

[Pavel Zhigulin]

The loops in 'qede_tpa_cont()' and 'qede_tpa_end()', iterate
over 'cqe->len_list[]' using only a zero-length terminator as
the stopping condition. If the terminator was missing or
malformed, the loop could run past the end of the fixed-size array.

Add an explicit bound check using ARRAY_SIZE() in both loops to prevent
a potential out-of-bounds access.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: 55482edc25f0 ("qede: Add slowpath/fastpath support and enable hardware GRO")
Signed-off-by: Pavel Zhigulin <Pavel.Zhigulin at kaspersky.com>
---
 drivers/net/ethernet/qlogic/qede/qede_fp.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/qlogic/qede/qede_fp.c b/drivers/net/ethernet/qlogic/qede/qede_fp.c
index 847fa62c80df..e338bfc8b7b2 100644
--- a/drivers/net/ethernet/qlogic/qede/qede_fp.c
+++ b/drivers/net/ethernet/qlogic/qede/qede_fp.c
@@ -4,6 +4,7 @@
  * Copyright (c) 2019-2020 Marvell International Ltd.
  */

+#include <linux/array_size.h>
 #include <linux/netdevice.h>
 #include <linux/etherdevice.h>
 #include <linux/skbuff.h>
@@ -960,7 +961,7 @@ static inline void qede_tpa_cont(struct qede_dev *edev,
 {
 	int i;

-	for (i = 0; cqe->len_list[i]; i++)
+	for (i = 0; cqe->len_list[i] && i < ARRAY_SIZE(cqe->len_list); i++)
 		qede_fill_frag_skb(edev, rxq, cqe->tpa_agg_index,
 				   le16_to_cpu(cqe->len_list[i]));

@@ -985,7 +986,7 @@ static int qede_tpa_end(struct qede_dev *edev,
 		dma_unmap_page(rxq->dev, tpa_info->buffer.mapping,
 			       PAGE_SIZE, rxq->data_direction);

-	for (i = 0; cqe->len_list[i]; i++)
+	for (i = 0; cqe->len_list[i] && i < ARRAY_SIZE(cqe->len_list); i++)
 		qede_fill_frag_skb(edev, rxq, cqe->tpa_agg_index,
 				   le16_to_cpu(cqe->len_list[i]));
 	if (unlikely(i > 1))
--
2.43.0