[PATCH] CAN: make checking in can_rcv less restrictive

From: Luotao Fu
Date: Thu Aug 06 2009 - 11:25:11 EST


From: Michael Olbrich <m.olbrich@xxxxxxxxxxxxxx>

Checking for can frame format in can_rcv() is too restrictive. BUG_ON is way too
heavy for the case that the can interface probably received a can frame with
malicious format. Further it can be used for DDOS attack since BUG_ON can lead
to kernel panic. Hence we turn this to WARN_ON instead.

Signed-off-by: Michael Olbrich <m.olbrich@xxxxxxxxxxxxxx>
Signed-off-by: Luotao Fu <l.fu@xxxxxxxxxxxxxx>
---
net/can/af_can.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/net/can/af_can.c b/net/can/af_can.c
index e733725..e6dcf4b 100644
--- a/net/can/af_can.c
+++ b/net/can/af_can.c
@@ -656,7 +656,7 @@ static int can_rcv(struct sk_buff *skb, struct net_device *dev,
return 0;
}

- BUG_ON(skb->len != sizeof(struct can_frame) || cf->can_dlc > 8);
+ WARN_ON(skb->len != sizeof(struct can_frame) || cf->can_dlc > 8);

/* update statistics */
can_stats.rx_frames++;
--
1.6.3.3

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