Re: [syzbot] [kernel?] KASAN: global-out-of-bounds Read in bus_uevent_store

[Edward Adam Davis <eadavis@sina.com>]

From: Edward Aadm Davis <eadavis@sina.com>

#syz test: upstream 50d05c7c76c9

diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c
index ddbc4d7482d2..25c89a36fb39 100644
--- a/lib/kobject_uevent.c
+++ b/lib/kobject_uevent.c
@@ -83,7 +83,8 @@ static int kobject_action_type(const char *buf, size_t count,
 	for (action = 0; action < ARRAY_SIZE(kobject_actions); action++) {
 		if (strncmp(kobject_actions[action], buf, count_first) != 0)
 			continue;
-		if (kobject_actions[action][count_first] != '\0')
+		if (count_first <= strlen(kobject_actions[action]) &&
+		    kobject_actions[action][count_first] != '\0')
 			continue;
 		if (args)
 			*args = args_start;