From: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx> Subject: lib/test_lockup.c: fix return value of test_lockup_init() Since filp_open() returns an error pointer, we should use IS_ERR() to check the return value and then return PTR_ERR() if failed to get the actual return value instead of always -EINVAL. E.g. without this patch: [root@localhost loongson]# ls no_such_file ls: cannot access no_such_file: No such file or directory [root@localhost loongson]# modprobe test_lockup file_path=no_such_file lock_sb_umount time_secs=60 state=S modprobe: ERROR: could not insert 'test_lockup': Invalid argument [root@localhost loongson]# dmesg | tail -1 [ 126.100596] test_lockup: cannot find file_path With this patch: [root@localhost loongson]# ls no_such_file ls: cannot access no_such_file: No such file or directory [root@localhost loongson]# modprobe test_lockup file_path=no_such_file lock_sb_umount time_secs=60 state=S modprobe: ERROR: could not insert 'test_lockup': Unknown symbol in module, or unknown parameter (see dmesg) [root@localhost loongson]# dmesg | tail -1 [ 95.134362] test_lockup: failed to open no_such_file: -2 Link: http://lkml.kernel.org/r/1595555407-29875-2-git-send-email-yangtiezhu@xxxxxxxxxxx Fixes: aecd42df6d39 ("lib/test_lockup.c: add parameters for locking generic vfs locks") Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx> Reviewed-by: Guenter Roeck <linux@xxxxxxxxxxxx> Cc: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx> Cc: Kees Cook <keescook@xxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- lib/test_lockup.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/lib/test_lockup.c~lib-test_lockupc-fix-return-value-of-test_lockup_init +++ a/lib/test_lockup.c @@ -512,8 +512,8 @@ static int __init test_lockup_init(void) if (test_file_path[0]) { test_file = filp_open(test_file_path, O_RDONLY, 0); if (IS_ERR(test_file)) { - pr_err("cannot find file_path\n"); - return -EINVAL; + pr_err("failed to open %s: %ld\n", test_file_path, PTR_ERR(test_file)); + return PTR_ERR(test_file); } test_inode = file_inode(test_file); } else if (test_lock_inode || _
