[SRU][J][PATCH 5/6] selftests/net: change shebang to bash to support "source"

[Ian Whitfield]

From: Yujie Liu <yujie.liu at intel.com>

BugLink: https://bugs.launchpad.net/bugs/2055473

The patch set [1] added a general lib.sh in net selftests, and converted
several test scripts to source the lib.sh.

unicast_extensions.sh (converted in [1]) and pmtu.sh (converted in [2])
have a /bin/sh shebang which may point to various shells in different
distributions, but "source" is only available in some of them. For
example, "source" is a built-it function in bash, but it cannot be
used in dash.

Refer to other scripts that were converted together, simply change the
shebang to bash to fix the following issues when the default /bin/sh
points to other shells.

not ok 51 selftests: net: unicast_extensions.sh # exit=1

v1 -> v2:
  - Fix pmtu.sh which has the same issue as unicast_extensions.sh,
    suggested by Hangbin
  - Change the style of the "source" line to be consistent with other
    tests, suggested by Hangbin

Link: https://lore.kernel.org/all/20231202020110.362433-1-liuhangbin@gmail.com/ [1]
Link: https://lore.kernel.org/all/20231219094856.1740079-1-liuhangbin@gmail.com/ [2]
Reported-by: kernel test robot <oliver.sang at intel.com>
Fixes: 378f082eaf37 ("selftests/net: convert pmtu.sh to run it in unique namespace")
Fixes: 0f4765d0b48d ("selftests/net: convert unicast_extensions.sh to run it in unique namespace")
Signed-off-by: Yujie Liu <yujie.liu at intel.com>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel at intel.com>
Reviewed-by: Hangbin Liu <liuhangbin at gmail.com>
Reviewed-by: Muhammad Usama Anjum <usama.anjum at collabora.com>
Link: https://lore.kernel.org/r/20231229131931.3961150-1-yujie.liu@intel.com
Signed-off-by: Jakub Kicinski <kuba at kernel.org>
(cherry picked from commit 05d92cb0e919239c29b3a26da1f76f1e18fed7d3)
Signed-off-by: Ian Whitfield <ian.whitfield at canonical.com>
---
 tools/testing/selftests/net/pmtu.sh               | 4 ++--
 tools/testing/selftests/net/unicast_extensions.sh | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/net/pmtu.sh b/tools/testing/selftests/net/pmtu.sh
index b431e9a2d2115..a1002c387fbfd 100755
--- a/tools/testing/selftests/net/pmtu.sh
+++ b/tools/testing/selftests/net/pmtu.sh
@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/bash
 # SPDX-License-Identifier: GPL-2.0
 #
 # Check that route PMTU values match expectations, and that initial device MTU
@@ -204,7 +204,7 @@
 #	addresses have multipath routes to each other, b_r1 mtu = 1500.
 #	Check that PMTU exceptions are created for both paths.
 
-source ./lib.sh
+source lib.sh
 
 PAUSE_ON_FAIL=no
 VERBOSE=0
diff --git a/tools/testing/selftests/net/unicast_extensions.sh b/tools/testing/selftests/net/unicast_extensions.sh
index b7a2cb9e74778..f52aa5f7da524 100755
--- a/tools/testing/selftests/net/unicast_extensions.sh
+++ b/tools/testing/selftests/net/unicast_extensions.sh
@@ -1,4 +1,4 @@
-#!/bin/sh
+#!/bin/bash
 # SPDX-License-Identifier: GPL-2.0
 #
 # By Seth Schoen (c) 2021, for the IPv4 Unicast Extensions Project
@@ -28,7 +28,7 @@
 # These tests provide an easy way to flip the expected result of any
 # of these behaviors for testing kernel patches that change them.
 
-source ./lib.sh
+source lib.sh
 
 # nettest can be run from PATH or from same directory as this selftest
 if ! which nettest >/dev/null; then
-- 
2.43.0