On Sun, Oct 20, 2019 at 06:17:42PM -0400, Joel Savitz wrote:
> When one attempts to create a directory in /proc with an invalid name,
> such as one in a subdirectory that doesn't exist, one with a name beyond
> 256 characters, or a reserved name such as '.' or '..', the kernel
> throws a warning message that looks like this:
>
> [ 7913.252558] name 'invalid_name'
Yes, the important part is filename:line which uniquely identifies
the issue.
> This warning message is nearly the same for all invalid cases, including
> the removal of a nonexistent directory. This patch clarifies the warning
> message and differentiates the invalid creation/removal cases so as to
> allow the user to more quickly understand their mistake.
> --- a/fs/proc/generic.c
> +++ b/fs/proc/generic.c
> @@ -173,7 +173,7 @@ static int __xlate_proc_name(const char *name, struct
> proc_dir_entry **ret,
> len = next - cp;
> de = pde_subdir_find(de, cp, len);
> if (!de) {
> - WARN(1, "name '%s'\n", name);
> + WARN(1, "invalid proc dir name '%s'\n", name);
Wrong string anyway, this is nonexistent name, directory or not.
> - WARN(1, "name len %u\n", qstr.len);
> + WARN(1, "invalid proc dir name len %u\n", qstr.len);
> return NULL;
> }
> if (qstr.len == 1 && fn[0] == '.') {
> - WARN(1, "name '.'\n");
> + WARN(1, "invalid proc dir name '.'\n");
> return NULL;
> }
> if (qstr.len == 2 && fn[0] == '.' && fn[1] == '.') {
> - WARN(1, "name '..'\n");
> + WARN(1, "invalid proc dir name '..'\n");
> return NULL;
> }
> if (*parent == &proc_root && name_to_int(&qstr) != ~0U) {
> @@ -402,7 +402,7 @@ static struct proc_dir_entry *__proc_create(struct
> proc_dir_entry **parent,
> return NULL;
> }
> if (is_empty_pde(*parent)) {
> - WARN(1, "attempt to add to permanently empty directory");
> + WARN(1, "attempt to add to permanently empty directory in
> proc");
"proc" will be spilled over all backtrace.
> @@ -670,7 +670,7 @@ void remove_proc_entry(const char *name, struct
> proc_dir_entry *parent)
> rb_erase(&de->subdir_node, &parent->subdir);
> write_unlock(&proc_subdir_lock);
> if (!de) {
> - WARN(1, "name '%s'\n", name);
> + WARN(1, "unable to remove nonexistent proc dir '%s'\n", name);
I'm not sure if such chatty strings are necessary.
