netdev - [PATCH] Fix NULL pointer dereference on firmware name for early calls to 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-next>] [day] [month] [year] [list]

Date:	Fri, 30 Mar 2012 16:24:05 -0400
From:	Bill Nottingham <notting@...hat.com>
To:	inaky.perez-gonzalez@...el.com, wimax@...uxwimax.org,
	netdev@...r.kernel.org
Subject: [PATCH] Fix NULL pointer dereference on firmware name for early calls to get_drvinfo.

The driver comments show an initialization sequence of:
 * i2400m_setup()
 *   i2400m->bus_setup()
 *   i2400m_bootrom_init()
 *   register_netdev()
 *   wimax_dev_add()
 *   i2400m_dev_start()
 *     __i2400m_dev_start()
 *       i2400m_dev_bootstrap()

dev_bootstrap() is where the firmware is loaded. So, if something calls
get_drvinfo() from a register_netdevice_notifier (such as the cnic driver),
we won't have a firmware name, and strncpy will crash.

https://bugzilla.redhat.com/show_bug.cgi?id=808603

Signed-off-by: Bill Nottingham <notting@...hat.com>
---
 drivers/net/wimax/i2400m/netdev.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wimax/i2400m/netdev.c b/drivers/net/wimax/i2400m/netdev.c
index 63e4b70..e44f4e2 100644
--- a/drivers/net/wimax/i2400m/netdev.c
+++ b/drivers/net/wimax/i2400m/netdev.c
@@ -597,7 +597,8 @@ static void i2400m_get_drvinfo(struct net_device *net_dev,
 	struct i2400m *i2400m = net_dev_to_i2400m(net_dev);
 
 	strncpy(info->driver, KBUILD_MODNAME, sizeof(info->driver) - 1);
-	strncpy(info->fw_version, i2400m->fw_name, sizeof(info->fw_version) - 1);
+	if (i2400m->fw_name)
+		strncpy(info->fw_version, i2400m->fw_name, sizeof(info->fw_version) - 1);
 	if (net_dev->dev.parent)
 		strncpy(info->bus_info, dev_name(net_dev->dev.parent),
 			sizeof(info->bus_info) - 1);
-- 
1.7.9.3

--
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