[PATCH AUTOSEL 4.19 20/25] ax88172a: fix information leak on short answers
From: Sasha Levin <sashal@kernel.org>
Date: 2019-11-22 19:53:33
Also in:
linux-usb, lkml, stable
Subsystem:
networking drivers, the rest, usb networking drivers · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Oliver Neukum <oneukum@suse.com> [ Upstream commit a9a51bd727d141a67b589f375fe69d0e54c4fe22 ] If a malicious device gives a short MAC it can elicit up to 5 bytes of leaked memory out of the driver. We need to check for ETH_ALEN instead. Reported-by: syzbot+a8d4acdad35e6bbca308@syzkaller.appspotmail.com Signed-off-by: Oliver Neukum <oneukum@suse.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org> --- drivers/net/usb/ax88172a.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/net/usb/ax88172a.c b/drivers/net/usb/ax88172a.c
index 501576f538546..914cac55a7ae7 100644
--- a/drivers/net/usb/ax88172a.c
+++ b/drivers/net/usb/ax88172a.c@@ -208,7 +208,7 @@ static int ax88172a_bind(struct usbnet *dev, struct usb_interface *intf) /* Get the MAC address */ ret = asix_read_cmd(dev, AX_CMD_READ_NODE_ID, 0, 0, ETH_ALEN, buf, 0); - if (ret < 0) { + if (ret < ETH_ALEN) { netdev_err(dev->net, "Failed to read MAC address: %d\n", ret); goto free; }
--
2.20.1