linux-kernel - [PATCH 3.16 082/202] skge: potential memory corruption in skge_get

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

Message-ID: <lsq.1556377989.399779912@decadent.org.uk>
Date:   Sat, 27 Apr 2019 16:13:09 +0100
From:   Ben Hutchings <ben@...adent.org.uk>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
CC:     akpm@...ux-foundation.org, Denis Kirjanov <kda@...ux-powerpc.org>,
        "Dan Carpenter" <dan.carpenter@...cle.com>,
        "David S. Miller" <davem@...emloft.net>
Subject: [PATCH 3.16 082/202] skge: potential memory corruption in
 skge_get_regs()

3.16.66-rc1 review patch.  If anyone has any objections, please let me know.

------------------

From: Dan Carpenter <dan.carpenter@...cle.com>

commit 294c149a209c6196c2de85f512b52ef50f519949 upstream.

The "p" buffer is 0x4000 bytes long.  B3_RI_WTO_R1 is 0x190.  The value
of "regs->len" is in the 1-0x4000 range.  The bug here is that
"regs->len - B3_RI_WTO_R1" can be a negative value which would lead to
memory corruption and an abrupt crash.

Fixes: c3f8be961808 ("[PATCH] skge: expand ethtool debug register dump")
Signed-off-by: Dan Carpenter <dan.carpenter@...cle.com>
Signed-off-by: David S. Miller <davem@...emloft.net>
Signed-off-by: Ben Hutchings <ben@...adent.org.uk>
---
 drivers/net/ethernet/marvell/skge.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

--- a/drivers/net/ethernet/marvell/skge.c
+++ b/drivers/net/ethernet/marvell/skge.c
@@ -152,8 +152,10 @@ static void skge_get_regs(struct net_dev
 	memset(p, 0, regs->len);
 	memcpy_fromio(p, io, B3_RAM_ADDR);
 
-	memcpy_fromio(p + B3_RI_WTO_R1, io + B3_RI_WTO_R1,
-		      regs->len - B3_RI_WTO_R1);
+	if (regs->len > B3_RI_WTO_R1) {
+		memcpy_fromio(p + B3_RI_WTO_R1, io + B3_RI_WTO_R1,
+			      regs->len - B3_RI_WTO_R1);
+	}
 }
 
 /* Wake on Lan only supported on Yukon chips with rev 1 or above */