[PATCH net-next] selftests: psock_tpacket: fix status check

[PATCH net-next] selftests: psock_tpacket: fix status check

[Daniel Borkmann]

Testing like this for TP_STATUS_AVAILABLE clearly is a stupid bug
since it always returns true. Fix this by only checking for flags
where the kernel owns the packet and negate this result, since we
also could run into the non-zero status TP_STATUS_WRONG_FORMAT
and need to reclaim frames.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
---
 This is only for net-next, since net does not contain networking
 selftests yet.

 tools/testing/selftests/net/psock_tpacket.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/net/psock_tpacket.c b/tools/testing/selftests/net/psock_tpacket.c
index a8d7ffa..c41b586 100644
--- a/tools/testing/selftests/net/psock_tpacket.c
+++ b/tools/testing/selftests/net/psock_tpacket.c
@@ -300,7 +300,7 @@ static void walk_v1_v2_rx(int sock, struct ring *ring)
 
 static inline int __v1_tx_kernel_ready(struct tpacket_hdr *hdr)
 {
-	return ((hdr->tp_status & TP_STATUS_AVAILABLE) == TP_STATUS_AVAILABLE);
+	return !(hdr->tp_status & (TP_STATUS_SEND_REQUEST | TP_STATUS_SENDING));
 }
 
 static inline void __v1_tx_user_ready(struct tpacket_hdr *hdr)
@@ -311,7 +311,7 @@ static inline void __v1_tx_user_ready(struct tpacket_hdr *hdr)
 
 static inline int __v2_tx_kernel_ready(struct tpacket2_hdr *hdr)
 {
-	return ((hdr->tp_status & TP_STATUS_AVAILABLE) == TP_STATUS_AVAILABLE);
+	return !(hdr->tp_status & (TP_STATUS_SEND_REQUEST | TP_STATUS_SENDING));
 }
 
 static inline void __v2_tx_user_ready(struct tpacket2_hdr *hdr)
-- 
1.7.11.7

Re: [PATCH net-next] selftests: psock_tpacket: fix status check

[David Miller]

From: Daniel Borkmann <dborkman@redhat.com>
Date: Thu, 25 Apr 2013 11:08:00 +0200

> Testing like this for TP_STATUS_AVAILABLE clearly is a stupid bug
> since it always returns true. Fix this by only checking for flags
> where the kernel owns the packet and negate this result, since we
> also could run into the non-zero status TP_STATUS_WRONG_FORMAT
> and need to reclaim frames.
> 
> Signed-off-by: Daniel Borkmann <dborkman@redhat.com>

Applied, thanks.