[PATCH net-next 0/2] fix two more udp pull header issues

[PATCH net-next 0/2] fix two more udp pull header issues

[Willem de Bruijn]

From: Willem de Bruijn <willemb@google.com>

Follow up patches to the fixes to RxRPC and SunRPC. A scan of the
code showed two other interfaces that expect UDP packets to have
a udphdr when queued: read packet length with ioctl SIOCINQ and
receive payload checksum with socket option IP_CHECKSUM.

Willem de Bruijn (2):
  udp: do not expect udp headers on ioctl SIOCINQ
  udp: do not expect udp headers in recv cmsg IP_CMSG_CHECKSUM

 net/ipv4/ip_sockglue.c | 3 ++-
 net/ipv4/udp.c         | 4 +---
 2 files changed, 3 insertions(+), 4 deletions(-)

-- 
2.8.0.rc3.226.g39d4020

[PATCH net-next 1/2] udp: do not expect udp headers on ioctl SIOCINQ

[Willem de Bruijn]

From: Willem de Bruijn <willemb@google.com>

On udp sockets, ioctl SIOCINQ returns the payload size of the first
packet. Since commit e6afc8ace6dd pulled the headers, the result is
incorrect when subtracting header length. Remove that operation.

Fixes: e6afc8ace6dd ("udp: remove headers from UDP packets before queueing")

Signed-off-by: Willem de Bruijn <willemb@google.com>
---
 net/ipv4/udp.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 3563788d..d2d294b 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -1282,8 +1282,6 @@ int udp_ioctl(struct sock *sk, int cmd, unsigned long arg)
 			 * of this packet since that is all
 			 * that will be read.
 			 */
-			amount -= sizeof(struct udphdr);
-
 		return put_user(amount, (int __user *)arg);
 	}
 
-- 
2.8.0.rc3.226.g39d4020

Re: [PATCH net-next 0/2] fix two more udp pull header issues

[David Miller]

From: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
Date: Thu,  7 Apr 2016 18:12:57 -0400

> Follow up patches to the fixes to RxRPC and SunRPC. A scan of the
> code showed two other interfaces that expect UDP packets to have
> a udphdr when queued: read packet length with ioctl SIOCINQ and
> receive payload checksum with socket option IP_CHECKSUM.

As we are seeing, lots of places depend upon the old way of queueing
up UDP frames. :-/

Applied, thanks for mopping all of this up.

Re: [PATCH net-next 0/2] fix two more udp pull header issues

[Willem de Bruijn]

On Wed, Apr 13, 2016 at 10:25 PM, David Miller <davem@davemloft.net> wrote:
> From: Willem de Bruijn <willemdebruijn.kernel@gmail.com>
> Date: Thu,  7 Apr 2016 18:12:57 -0400
>
>> Follow up patches to the fixes to RxRPC and SunRPC. A scan of the
>> code showed two other interfaces that expect UDP packets to have
>> a udphdr when queued: read packet length with ioctl SIOCINQ and
>> receive payload checksum with socket option IP_CHECKSUM.
>
> As we are seeing, lots of places depend upon the old way of queueing
> up UDP frames. :-/

Yes, I greatly underestimated that. I should have done a much more
thorough scan before submitting. Hopefully we've caught them all now.

> Applied, thanks for mopping all of this up.

Apologies for breaking it in the first place!