netdev - [PATCH] rps: fix insufficient bounds checking in store_rps_dev_flow_table

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <1324493459-19764-1-git-send-email-xi.wang@gmail.com>
Date:	Wed, 21 Dec 2011 13:50:59 -0500
From:	Xi Wang <xi.wang@...il.com>
To:	Tom Herbert <therbert@...gle.com>,
	"David S. Miller" <davem@...emloft.net>
Cc:	netdev@...r.kernel.org, Xi Wang <xi.wang@...il.com>
Subject: [PATCH] rps: fix insufficient bounds checking in store_rps_dev_flow_table_cnt()

Setting a large rps_flow_cnt like 1073741824 (1 << 30) on 32-bit
platform will cause a kernel oops due to insufficient bounds checking.

	if (count > 1<<30) {
		/* Enforce a limit to prevent overflow */
		return -EINVAL;
	}
	count = roundup_pow_of_two(count);
	table = vmalloc(RPS_DEV_FLOW_TABLE_SIZE(count));

Note that the macro RPS_DEV_FLOW_TABLE_SIZE(count) is defined as:

	... + (count * sizeof(struct rps_dev_flow))

where sizeof(struct rps_dev_flow) is 8.  (1 << 30) * 8 will overflow
32 bits.  This patch changes the upper bound to (1 << 28).

Signed-off-by: Xi Wang <xi.wang@...il.com>
---
 net/core/net-sysfs.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index c71c434..f53a947 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -665,7 +665,7 @@ static ssize_t store_rps_dev_flow_table_cnt(struct netdev_rx_queue *queue,
 	if (count) {
 		int i;
 
-		if (count > 1<<30) {
+		if (count > 1<<28) {
 			/* Enforce a limit to prevent overflow */
 			return -EINVAL;
 		}
-- 
1.7.5.4

--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html