[PATCH] lib/test_kmod: Fix a use after free in register_test_dev_kmod

[Lv Yunlong]

In register_test_dev_kmod, it calls free_test_dev_kmod() to free
test_dev. But free_test_dev_kmod() can't set the original pointer
test_dev to NULL, because the test_dev was passed by it's value
not reference.

Signed-off-by: Lv Yunlong <lyl2...@mail.ustc.edu.cn>
---
 lib/test_kmod.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/test_kmod.c b/lib/test_kmod.c
index 38c250fbace3..aa8a2a563d7e 100644
--- a/lib/test_kmod.c
+++ b/lib/test_kmod.c
@@ -1124,7 +1124,6 @@ static void free_test_dev_kmod(struct kmod_test_device 
*test_dev)
                free_test_dev_info(test_dev);
                kmod_config_free(test_dev);
                vfree(test_dev);
-               test_dev = NULL;
        }
 }
 
@@ -1149,6 +1148,7 @@ static struct kmod_test_device 
*register_test_dev_kmod(void)
        if (ret) {
                pr_err("could not register misc device: %d\n", ret);
                free_test_dev_kmod(test_dev);
+               test_dev = NULL;
                goto out;
        }
 
-- 
2.25.1