commit a2d375eda771 ("dyndbg: refine export, rename to dynamic_debug_exec_queries()")
Above commit copies a string before checking for null pointer, fix
this, and add a pr_err. Also trim comment, and add return val info.
Fixes: a2d375eda771
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Jim Cromie <jim.cromie@xxxxxxxxx>
---
lib/dynamic_debug.c | 18 ++++++++++++------
1 file changed, 12 insertions(+), 6 deletions(-)
diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index bd7b3aaa93c3..711a9def8c83 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -553,17 +553,23 @@ static int ddebug_exec_queries(char *query, const char *modname)
* @query: query-string described in admin-guide/dynamic-debug-howto
* @modname: string containing module name, usually &module.mod_name
*
- * This uses the >/proc/dynamic_debug/control reader, allowing module
- * authors to modify their dynamic-debug callsites. The modname is
- * canonically struct module.mod_name, but can also be null or a
- * module-wildcard, for example: "drm*".
+ * This uses the >control reader, allowing module authors to modify
+ * their dynamic-debug callsites. The modname is canonically struct
+ * module.mod_name, but can also be null or a module-wildcard, for
+ * example: "drm*".
+ * Returns <0 on error, >=0 for callsites changed
*/
int dynamic_debug_exec_queries(const char *query, const char *modname)
{
int rc;
- char *qry = kstrndup(query, PAGE_SIZE, GFP_KERNEL);
+ char *qry; /* writable copy of query */
- if (!query)
+ if (!query) {
+ pr_err("non-null query/command string expected\n");
+ return -EINVAL;
+ }
+ qry = kstrndup(query, PAGE_SIZE, GFP_KERNEL);
+ if (!qry)
return -ENOMEM;
rc = ddebug_exec_queries(qry, modname);
--
2.28.0
