From: Eric Biggers <ebiggers@xxxxxxxxxx> Subject: selftests: kmod: test disabling module autoloading Test that request_module() fails with -ENOENT when /proc/sys/kernel/modprobe contains (a) a nonexistent path, and (b) an empty path. Case (b) is a regression test for the patch "kmod: make request_module() return an error when autoloading is disabled". Tested with 'kmod.sh -t 0010 && kmod.sh -t 0011', and also simply with 'kmod.sh' to run all kmod tests. Link: http://lkml.kernel.org/r/20200312202552.241885-5-ebiggers@xxxxxxxxxx Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx> Acked-by: Luis Chamberlain <mcgrof@xxxxxxxxxx> Cc: Alexei Starovoitov <ast@xxxxxxxxxx> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: Jeff Vander Stoep <jeffv@xxxxxxxxxx> Cc: Jessica Yu <jeyu@xxxxxxxxxx> Cc: Kees Cook <keescook@xxxxxxxxxxxx> Cc: NeilBrown <neilb@xxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- tools/testing/selftests/kmod/kmod.sh | 30 +++++++++++++++++++++++++ 1 file changed, 30 insertions(+) --- a/tools/testing/selftests/kmod/kmod.sh~selftests-kmod-test-disabling-module-autoloading +++ a/tools/testing/selftests/kmod/kmod.sh @@ -61,6 +61,8 @@ ALL_TESTS="$ALL_TESTS 0006:10:1" ALL_TESTS="$ALL_TESTS 0007:5:1" ALL_TESTS="$ALL_TESTS 0008:150:1" ALL_TESTS="$ALL_TESTS 0009:150:1" +ALL_TESTS="$ALL_TESTS 0010:1:1" +ALL_TESTS="$ALL_TESTS 0011:1:1" # Kselftest framework requirement - SKIP code is 4. ksft_skip=4 @@ -149,6 +151,7 @@ function load_req_mod() test_finish() { + echo "$MODPROBE" > /proc/sys/kernel/modprobe echo "Test completed" } @@ -443,6 +446,30 @@ kmod_test_0009() config_expect_result ${FUNCNAME[0]} SUCCESS } +kmod_test_0010() +{ + kmod_defaults_driver + config_num_threads 1 + echo "/KMOD_TEST_NONEXISTENT" > /proc/sys/kernel/modprobe + config_trigger ${FUNCNAME[0]} + config_expect_result ${FUNCNAME[0]} -ENOENT + echo "$MODPROBE" > /proc/sys/kernel/modprobe +} + +kmod_test_0011() +{ + kmod_defaults_driver + config_num_threads 1 + # This causes the kernel to not even try executing modprobe. The error + # code is still -ENOENT like when modprobe doesn't exist, so we can't + # easily test for the exact difference. But this still is a useful test + # since there was a bug where request_module() returned 0 in this case. + echo > /proc/sys/kernel/modprobe + config_trigger ${FUNCNAME[0]} + config_expect_result ${FUNCNAME[0]} -ENOENT + echo "$MODPROBE" > /proc/sys/kernel/modprobe +} + list_tests() { echo "Test ID list:" @@ -460,6 +487,8 @@ list_tests() echo "0007 x $(get_test_count 0007) - multithreaded tests with default setup test request_module() and get_fs_type()" echo "0008 x $(get_test_count 0008) - multithreaded - push kmod_concurrent over max_modprobes for request_module()" echo "0009 x $(get_test_count 0009) - multithreaded - push kmod_concurrent over max_modprobes for get_fs_type()" + echo "0010 x $(get_test_count 0010) - test nonexistent modprobe path" + echo "0011 x $(get_test_count 0011) - test completely disabling module autoloading" } usage() @@ -616,6 +645,7 @@ test_reqs allow_user_defaults load_req_mod +MODPROBE=$(</proc/sys/kernel/modprobe) trap "test_finish" EXIT parse_args $@ _
