selftests/livepatch: fix mem leaks in test-klp-shadow-vars

In some cases, when an error occurs during testing and the main test
routine returns, a memory leak occurs via leaving previously registered
shadow variables allocated in the kernel as well as shadow_ptr list
elements. From now on, in case of error, remove all allocated shadow
variables and shadow_ptr struct elements.

Signed-off-by: Yannick Cote <ycote@redhat.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20200603182058.109470-5-ycote@redhat.com

diff --git a/lib/livepatch/test_klp_shadow_vars.c b/lib/livepatch/test_klp_shadow_vars.c
index a49265e56917fb6dbd6f411f53daa16f7e320919..b991164908587e4f1ae3e59fc6599d0f9ad3e96c 100644 (file)
--- a/lib/livepatch/test_klp_shadow_vars.c
+++ b/lib/livepatch/test_klp_shadow_vars.c
@@ -170,6 +170,7 @@ static int test_klp_shadow_vars_init(void)
        char *pndup[NUM_OBJS];
        int nfields2[NUM_OBJS], *pnfields2[NUM_OBJS], **sv2[NUM_OBJS];
        void **sv;
+       int ret;
        int i;
 
        ptr_id(NULL);
@@ -196,31 +197,39 @@ static int test_klp_shadow_vars_init(void)
                                        sizeof(pnfields1[i]), GFP_KERNEL,
                                        shadow_ctor, &pnfields1[i]);
                }
-               if (!sv1[i])
-                       return -ENOMEM;
+               if (!sv1[i]) {
+                       ret = -ENOMEM;
+                       goto out;
+               }
 
                pnfields2[i] = &nfields2[i];
                ptr_id(pnfields2[i]);
                sv2[i] = shadow_alloc(&objs[i], SV_ID2, sizeof(pnfields2[i]),
                                        GFP_KERNEL, shadow_ctor, &pnfields2[i]);
-               if (!sv2[i])
-                       return -ENOMEM;
+               if (!sv2[i]) {
+                       ret = -ENOMEM;
+                       goto out;
+               }
        }
 
        /* pass 2: verify we find allocated svars and where they point to */
        for (i = 0; i < NUM_OBJS; i++) {
                /* check the "char" svar for all objects */
                sv = shadow_get(&objs[i], SV_ID1);
-               if (!sv)
-                       return -EINVAL;
+               if (!sv) {
+                       ret = -EINVAL;
+                       goto out;
+               }
                if ((char **)sv == sv1[i] && *sv1[i] == pnfields1[i])
                        pr_info("  got expected PTR%d -> PTR%d result\n",
                                ptr_id(sv1[i]), ptr_id(*sv1[i]));
 
                /* check the "int" svar for all objects */
                sv = shadow_get(&objs[i], SV_ID2);
-               if (!sv)
-                       return -EINVAL;
+               if (!sv) {
+                       ret = -EINVAL;
+                       goto out;
+               }
                if ((int **)sv == sv2[i] && *sv2[i] == pnfields2[i])
                        pr_info("  got expected PTR%d -> PTR%d result\n",
                                ptr_id(sv2[i]), ptr_id(*sv2[i]));
@@ -233,8 +242,10 @@ static int test_klp_shadow_vars_init(void)
 
                sv = shadow_get_or_alloc(&objs[i], SV_ID1, sizeof(pndup[i]),
                                        GFP_KERNEL, shadow_ctor, &pndup[i]);
-               if (!sv)
-                       return -EINVAL;
+               if (!sv) {
+                       ret = -EINVAL;
+                       goto out;
+               }
                if ((char **)sv == sv1[i] && *sv1[i] == pnfields1[i])
                        pr_info("  got expected PTR%d -> PTR%d result\n",
                                        ptr_id(sv1[i]), ptr_id(*sv1[i]));
@@ -251,8 +262,10 @@ static int test_klp_shadow_vars_init(void)
        /* pass 5: check we still find <objs[*], SV_ID2> svar pairs */
        for (i = 0; i < NUM_OBJS; i++) {
                sv = shadow_get(&objs[i], SV_ID2);      /* 'int' pairs */
-               if (!sv)
-                       return -EINVAL;
+               if (!sv) {
+                       ret = -EINVAL;
+                       goto out;
+               }
                if ((int **)sv == sv2[i] && *sv2[i] == pnfields2[i])
                        pr_info("  got expected PTR%d -> PTR%d result\n",
                                        ptr_id(sv2[i]), ptr_id(*sv2[i]));
@@ -269,6 +282,12 @@ static int test_klp_shadow_vars_init(void)
        free_ptr_list();
 
        return 0;
+out:
+       shadow_free_all(SV_ID1, NULL);          /* 'char' pairs */
+       shadow_free_all(SV_ID2, NULL);          /* 'int' pairs */
+       free_ptr_list();
+
+       return ret;
 }
 
 static void test_klp_shadow_vars_exit(void)