selftests: firmware: remove use of non-standard diff -Z option

"diff -Z" is used to trim the trailing whitespace when comparing the
loaded firmware file with the source firmware file. However, per the
comment in the source code, -Z should not be necessary. In testing, the
input and output files are identical.

Additionally, -Z is not a standard option and is not available in
environments such as busybox. When -Z is not supported, diff fails with
a usage error, which is suppressed, but then causes read_firmwares() to
exit with a false failure message.

Signed-off-by: Dan Rue <dan.rue@linaro.org>
Acked-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Shuah Khan <shuah@kernel.org>

diff --git a/tools/testing/selftests/firmware/fw_filesystem.sh b/tools/testing/selftests/firmware/fw_filesystem.sh
index a4320c4..466cf2f 100755 (executable)
--- a/tools/testing/selftests/firmware/fw_filesystem.sh
+++ b/tools/testing/selftests/firmware/fw_filesystem.sh
@@ -155,11 +155,8 @@ read_firmwares()
 {
        for i in $(seq 0 3); do
                config_set_read_fw_idx $i
-               # Verify the contents are what we expect.
-               # -Z required for now -- check for yourself, md5sum
-               # on $FW and DIR/read_firmware will yield the same. Even
-               # cmp agrees, so something is off.
-               if ! diff -q -Z "$FW" $DIR/read_firmware 2>/dev/null ; then
+               # Verify the contents match
+               if ! diff -q "$FW" $DIR/read_firmware 2>/dev/null ; then
                        echo "request #$i: firmware was not loaded" >&2
                        exit 1
                fi
@@ -171,7 +168,7 @@ read_firmwares_expect_nofile()
        for i in $(seq 0 3); do
                config_set_read_fw_idx $i
                # Ensures contents differ
-               if diff -q -Z "$FW" $DIR/read_firmware 2>/dev/null ; then
+               if diff -q "$FW" $DIR/read_firmware 2>/dev/null ; then
                        echo "request $i: file was not expected to match" >&2
                        exit 1
                fi