af_packet: tone down the Tx-ring unsupported spew.

af_packet: tone down the Tx-ring unsupported spew.

[Dave Jones]

Trinity and other fuzzers can hit this WARN on far too easily,
resulting in a tainted kernel that hinders automated fuzzing.

Replace it with a rate-limited printk.

Signed-off-by: Dave Jones <davej@codemonkey.org.uk>

diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 1ecfa710ca98..f12c17f355d9 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -4151,7 +4151,7 @@ static int packet_set_ring(struct sock *sk, union tpacket_req_u *req_u,
 
 	/* Opening a Tx-ring is NOT supported in TPACKET_V3 */
 	if (!closing && tx_ring && (po->tp_version > TPACKET_V2)) {
-		WARN(1, "Tx-ring is not supported.\n");
+		net_warn_ratelimited("Tx-ring is not supported.\n");
 		goto out;
 	}
 

Re: af_packet: tone down the Tx-ring unsupported spew.

[Daniel Borkmann]

On 04/04/2016 09:11 PM, Dave Jones wrote:
> Trinity and other fuzzers can hit this WARN on far too easily,
> resulting in a tainted kernel that hinders automated fuzzing.
>
> Replace it with a rate-limited printk.
>
> Signed-off-by: Dave Jones <davej@codemonkey.org.uk>

Acked-by: Daniel Borkmann <daniel@iogearbox.net>

Re: af_packet: tone down the Tx-ring unsupported spew.

[David Miller]

From: Dave Jones <davej@codemonkey.org.uk>
Date: Mon, 4 Apr 2016 15:11:50 -0400

> Trinity and other fuzzers can hit this WARN on far too easily,
> resulting in a tainted kernel that hinders automated fuzzing.
> 
> Replace it with a rate-limited printk.
> 
> Signed-off-by: Dave Jones <davej@codemonkey.org.uk>

Looks good, thanks Dave.