[PATCH net-next v4 02/12] selftests/vsock: make wait_for_listener() work even if pipefail is on

Bobby Eshleman posted 12 patches 1 month, 1 week ago
[PATCH net-next v4 02/12] selftests/vsock: make wait_for_listener() work even if pipefail is on
Posted by Bobby Eshleman 1 month, 1 week ago
From: Bobby Eshleman <bobbyeshleman@meta.com>

Rewrite wait_for_listener()'s pattern matching to avoid tripping the
if-condition when pipefail is on.

awk doesn't gracefully handle SIGPIPE with a non-zero exit code, so grep
exiting upon finding a match causes false-positives when the pipefail
option is used (grep exits, SIGPIPE emits, and awk complains with a
non-zero exit code). Instead, move all of the pattern matching into awk
so that SIGPIPE cannot happen and the correct exit code is returned.

Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com>
---
Changes in v2:
- use awk-only tcp port lookup
- remove fixes tag because this problem is only introduced when a later
  patch enables pipefail for other reasons (not yet in tree)
---
 tools/testing/selftests/vsock/vmtest.sh | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/vsock/vmtest.sh b/tools/testing/selftests/vsock/vmtest.sh
index bc16b13cdbe3..01ce16523afb 100755
--- a/tools/testing/selftests/vsock/vmtest.sh
+++ b/tools/testing/selftests/vsock/vmtest.sh
@@ -251,9 +251,11 @@ wait_for_listener()
 
 	# for tcp protocol additionally check the socket state
 	[ "${protocol}" = "tcp" ] && pattern="${pattern}0A"
+
 	for i in $(seq "${max_intervals}"); do
-		if awk '{print $2" "$4}' /proc/net/"${protocol}"* | \
-		   grep -q "${pattern}"; then
+		if awk -v pattern="${pattern}" \
+			'BEGIN {rc=1} $2" "$4 ~ pattern {rc=0} END {exit rc}' \
+			/proc/net/"${protocol}"*; then
 			break
 		fi
 		sleep "${interval}"

-- 
2.47.3
Re: [PATCH net-next v4 02/12] selftests/vsock: make wait_for_listener() work even if pipefail is on
Posted by Stefano Garzarella 1 month ago
On Sat, Nov 08, 2025 at 08:00:53AM -0800, Bobby Eshleman wrote:
>From: Bobby Eshleman <bobbyeshleman@meta.com>
>
>Rewrite wait_for_listener()'s pattern matching to avoid tripping the
>if-condition when pipefail is on.
>
>awk doesn't gracefully handle SIGPIPE with a non-zero exit code, so grep
>exiting upon finding a match causes false-positives when the pipefail
>option is used (grep exits, SIGPIPE emits, and awk complains with a
>non-zero exit code). Instead, move all of the pattern matching into awk
>so that SIGPIPE cannot happen and the correct exit code is returned.
>
>Signed-off-by: Bobby Eshleman <bobbyeshleman@meta.com>
>---
>Changes in v2:
>- use awk-only tcp port lookup
>- remove fixes tag because this problem is only introduced when a later
>  patch enables pipefail for other reasons (not yet in tree)
>---
> tools/testing/selftests/vsock/vmtest.sh | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)

Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>

>
>diff --git a/tools/testing/selftests/vsock/vmtest.sh b/tools/testing/selftests/vsock/vmtest.sh
>index bc16b13cdbe3..01ce16523afb 100755
>--- a/tools/testing/selftests/vsock/vmtest.sh
>+++ b/tools/testing/selftests/vsock/vmtest.sh
>@@ -251,9 +251,11 @@ wait_for_listener()
>
> 	# for tcp protocol additionally check the socket state
> 	[ "${protocol}" = "tcp" ] && pattern="${pattern}0A"
>+
> 	for i in $(seq "${max_intervals}"); do
>-		if awk '{print $2" "$4}' /proc/net/"${protocol}"* | \
>-		   grep -q "${pattern}"; then
>+		if awk -v pattern="${pattern}" \
>+			'BEGIN {rc=1} $2" "$4 ~ pattern {rc=0} END {exit rc}' \
>+			/proc/net/"${protocol}"*; then
> 			break
> 		fi
> 		sleep "${interval}"
>
>-- 
>2.47.3
>