[RFC] sierra: avoid trailing bytes leading to garbage parsing
From: Oliver Neukum <oneukum@suse.com>
Date: 2022-02-17 10:29:18
Also in:
linux-usb
Subsystem:
networking drivers, the rest, usb networking drivers, usb smsc75xx ethernet driver · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds, Steve Glendinning
The driver's main loop isn't ready for a device sending some trailing bytes as it tests for an exact match between package and accumulated frames. We would parse some garbage from the heap and follow its pointers. Signed-off-by: Oliver Neukum <oneukum@suse.com> --- drivers/net/usb/smsc75xx.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/net/usb/smsc75xx.c b/drivers/net/usb/smsc75xx.c
index 95de452ff4da..649e43b4df4f 100644
--- a/drivers/net/usb/smsc75xx.c
+++ b/drivers/net/usb/smsc75xx.c@@ -2183,7 +2183,8 @@ static int smsc75xx_rx_fixup(struct usbnet *dev, struct sk_buff *skb) if (skb->len < dev->net->hard_header_len) return 0; - while (skb->len > 0) { + /* at least two u32 must be left to go on */ + while (skb->len > 4 + 4) { u32 rx_cmd_a, rx_cmd_b, align_count, size; struct sk_buff *ax_skb; unsigned char *packet;
--
2.34.1