From: Mimi Zohar <zohar@xxxxxxxxxxxxx> Instead of assigning the string to a variable, which might contain a null character, redirect the output and grep for the string directly. Signed-off-by: Mimi Zohar <zohar@xxxxxxxxxxxxx> --- tools/testing/selftests/kexec/test_kexec_file_load.sh | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/kexec/test_kexec_file_load.sh b/tools/testing/selftests/kexec/test_kexec_file_load.sh index 2ff600388c30..99f6fc23ee31 100755 --- a/tools/testing/selftests/kexec/test_kexec_file_load.sh +++ b/tools/testing/selftests/kexec/test_kexec_file_load.sh @@ -97,10 +97,11 @@ check_for_imasig() check_for_modsig() { local module_sig_string="~Module signature appended~" - local sig="$(tail --bytes $((${#module_sig_string} + 1)) $KERNEL_IMAGE)" local ret=0 - if [ "$sig" == "$module_sig_string" ]; then + tail --bytes $((${#module_sig_string} + 1)) $KERNEL_IMAGE | \ + grep -q "$module_sig_string" + if [ $? -eq 0 ]; then ret=1 log_info "kexec kernel image modsig signed" else -- 2.23.0