[PATCH AUTOSEL 6.17-5.10] selftests: traceroute: Use require_command()

[Sasha Levin <sashal@kernel.org>]

From: Ido Schimmel <idosch@nvidia.com>

[ Upstream commit 47efbac9b768553331b9459743a29861e0acd797 ]

Use require_command() so that the test will return SKIP (4) when a
required command is not present.

Before:

 # ./traceroute.sh
 SKIP: Could not run IPV6 test without traceroute6
 SKIP: Could not run IPV4 test without traceroute
 $ echo $?
 0

After:

 # ./traceroute.sh
 TEST: traceroute6 not installed                                    [SKIP]
 $ echo $?
 4

Reviewed-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/20250908073238.119240-6-idosch@nvidia.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

LLM Generated explanations, may be completely bogus:

YES

- Fixes a real bug in selftests reporting: when traceroute binaries are
  missing, the script previously exited 0 (PASS) after printing a manual
  “SKIP” message, which hides missing test coverage from harnesses and
  CI. The change standardizes behavior to return the kselftest skip code
  (4), matching framework expectations.
- Small, contained change limited to selftests; no kernel code touched,
  no ABI or API impact, no architectural changes.

Specifics in the code:
- The script sources the common helpers, so `require_command()` is
  available: tools/testing/selftests/net/traceroute.sh:7.
- Inline, ad hoc checks are removed from the test bodies:
  - run_traceroute6(): drops the `command -v traceroute6` guard and
    manual “SKIP” echo shown in the diff.
  - run_traceroute(): drops the `command -v traceroute` guard and manual
    “SKIP” echo shown in the diff.
  This eliminates duplicate logic and prevents returning success on
missing deps.
- Centralized, framework-compliant dependency checks are added before
  running tests:
  - tools/testing/selftests/net/traceroute.sh:463 `require_command
    traceroute6`
  - tools/testing/selftests/net/traceroute.sh:464 `require_command
    traceroute`
- The helper `require_command()` is defined in the shared library:
  - tools/testing/selftests/net/lib.sh:537 `require_command()` calls
    `check_command`, which logs a SKIP via `log_test_skip` and then
    exits with `EXIT_STATUS`.
  - The kselftest constants define skip as 4:
    tools/testing/selftests/net/lib.sh:22 `ksft_skip=4`.
  Consequently, when the command is missing, the script prints “TEST:
<cmd> not installed [SKIP]” and exits 4, exactly as described in the
commit message.

Risk and compatibility:
- Effect is limited to how the test reports missing prerequisites. This
  aligns traceroute.sh with many other selftests already using
  `require_command` (e.g.,
  tools/testing/selftests/net/rtnetlink_notification.sh:108), improving
  consistency across the selftests suite.
- One behavioral change: if either `traceroute6` or `traceroute` is
  missing, the entire script will SKIP early rather than partially
  running the remaining tests. This is a reasonable and common selftests
  convention, and it avoids false PASS outcomes. It does not affect
  kernel behavior.

Stable backport criteria:
- Addresses test correctness and CI signal integrity (important for
  users running selftests).
- Minimal, localized change with very low regression risk.
- No features or architectural shifts; purely a selftest reliability
  fix.
- Consistent with established kselftest patterns and constants.

Given these points, this is a safe and beneficial selftest fix
appropriate for stable trees.

 tools/testing/selftests/net/traceroute.sh | 13 +++----------
 1 file changed, 3 insertions(+), 10 deletions(-)

diff --git a/tools/testing/selftests/net/traceroute.sh b/tools/testing/selftests/net/traceroute.sh
index 282f14760940d..b50e52afa4f49 100755
--- a/tools/testing/selftests/net/traceroute.sh
+++ b/tools/testing/selftests/net/traceroute.sh
@@ -203,11 +203,6 @@ setup_traceroute6()
 
 run_traceroute6()
 {
-	if [ ! -x "$(command -v traceroute6)" ]; then
-		echo "SKIP: Could not run IPV6 test without traceroute6"
-		return
-	fi
-
 	setup_traceroute6
 
 	# traceroute6 host-2 from host-1 (expects 2000:102::2)
@@ -268,11 +263,6 @@ setup_traceroute()
 
 run_traceroute()
 {
-	if [ ! -x "$(command -v traceroute)" ]; then
-		echo "SKIP: Could not run IPV4 test without traceroute"
-		return
-	fi
-
 	setup_traceroute
 
 	# traceroute host-2 from host-1 (expects 1.0.1.1). Takes a while.
@@ -306,6 +296,9 @@ do
 	esac
 done
 
+require_command traceroute6
+require_command traceroute
+
 run_tests
 
 printf "\nTests passed: %3d\n" ${nsuccess}
-- 
2.51.0