fix(finsh): validate backtrace thread address

Author: Telecaster2147

src/kservice.c

@@ -747,10 +747,64 @@ rt_uint8_t rt_thread_get_usage(rt_thread_t thread)
 #if defined(RT_USING_LIBC) && defined(RT_USING_FINSH)
 #include <stdlib.h> /* for string service */
 
-static void cmd_backtrace(int argc, char** argv)
+struct cmd_backtrace_find_ctx
 {
     rt_uintptr_t pid;
+    rt_thread_t thread;
+};
+
+static rt_err_t cmd_backtrace_match_thread(struct rt_object *object, void *data)
+{
+    struct cmd_backtrace_find_ctx *ctx = data;
+
+    if ((rt_uintptr_t)object == ctx->pid)
+    {
+        ctx->thread = (rt_thread_t)object;
+
+        return 1;
+    }
+
+    return RT_EOK;
+}
+
+static rt_bool_t cmd_backtrace_parse_pid(const char *arg, rt_uintptr_t *pid)
+{
     char *end_ptr;
+    rt_uintptr_t value;
+
+    if ((arg == RT_NULL) || (pid == RT_NULL))
+    {
+        return RT_FALSE;
+    }
+
+    value = (rt_uintptr_t)strtoul(arg, &end_ptr, 0);
+    if ((end_ptr == arg) || (*end_ptr != '\0') || (value == 0))
+    {
+        return RT_FALSE;
+    }
+
+    *pid = value;
+
+    return RT_TRUE;
+}
+
+static rt_thread_t cmd_backtrace_find_thread(rt_uintptr_t pid)
+{
+    struct cmd_backtrace_find_ctx ctx =
+    {
+        .pid = pid,
+        .thread = RT_NULL,
+    };
+
+    rt_object_for_each(RT_Object_Class_Thread, cmd_backtrace_match_thread, &ctx);
+
+    return ctx.thread;
+}
+
+static void cmd_backtrace(int argc, char** argv)
+{
+    rt_uintptr_t pid;
+    rt_thread_t target;
 
     if (argc != 2)
     {
@@ -770,21 +824,22 @@ static void cmd_backtrace(int argc, char** argv)
         }
     }
 
-    pid = strtoul(argv[1], &end_ptr, 0);
-    if (end_ptr == argv[1])
+    if (!cmd_backtrace_parse_pid(argv[1], &pid))
     {
         rt_kprintf("Invalid input: %s\n", argv[1]);
         return ;
     }
 
-    if (pid && rt_object_get_type((void *)pid) == RT_Object_Class_Thread)
+    target = cmd_backtrace_find_thread(pid);
+    if (target != RT_NULL)
     {
-        rt_thread_t target = (rt_thread_t)pid;
-        rt_kprintf("backtrace %s(0x%lx), from %s\n", target->parent.name, pid, argv[1]);
+        rt_kprintf("backtrace %s(0x%lx), from %s\n", target->parent.name, (unsigned long)pid, argv[1]);
         rt_backtrace_thread(target);
     }
     else
-        rt_kprintf("Invalid pid: %ld\n", pid);
+    {
+        rt_kprintf("Invalid pid: %lx\n", (unsigned long)pid);
+    }
 }
 MSH_CMD_EXPORT_ALIAS(cmd_backtrace, backtrace, print backtrace of a thread);