livepatch/klp-build: add grep-override function

Provide a custom grep() function to catch direct usage of the command.
Bare grep calls are generally incompatible with pipefail and
errexit behavior (where a failed match causes the script to exit).

Developers can still call grep via command grep if that behavior is
explicitly desired.

Acked-by: Song Liu <song@kernel.org>
Signed-off-by: Joe Lawrence <joe.lawrence@redhat.com>
Link: https://patch.msgid.link/20260310203751.1479229-6-joe.lawrence@redhat.com
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>

diff --git a/scripts/livepatch/klp-build b/scripts/livepatch/klp-build
index 564985a1588a224ab89c9bb24cea9c49377c94a6..cf6c2bf694aaea0fb5db8b93016ed50c3704c612 100755 (executable)
--- a/scripts/livepatch/klp-build
+++ b/scripts/livepatch/klp-build
@@ -56,6 +56,13 @@ grep0() {
        command grep "$@" || true
 }
 
+# Because pipefail is enabled, the grep0 helper should be used instead of
+# grep, otherwise a failed match can propagate to an error.
+grep() {
+       echo "error: $SCRIPT: use grep0 or 'command grep' instead of bare grep" >&2
+       exit 1
+}
+
 status() {
        echo "$*"
 }