depmod: fix errorpath memleaks in report cycles logic

The c7ce9f0c80f3d561078a78205a14c5ba7663cfdd commit (depmod:
handle nested loops) introduced a bunch of possible memory leaks
in error path. In the real world scenario it is not a problem,
since the utility quits if it detects any of the errors, but from
the programming point of view, it is not nice. So, add the
cleanups.

Signed-off-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>

diff --git a/tools/depmod.c b/tools/depmod.c
index 116adbeb14a0f53aa1821e446518c52cbce17be1..7f9e9804787eda453ddfb8e238f58053191bfd1e 100644 (file)
--- a/tools/depmod.c
+++ b/tools/depmod.c
@@ -1481,10 +1481,10 @@ static void depmod_list_remove_data(struct kmod_list **list, void *data)
        *list = l;
 }
 
-static void depmod_report_one_cycle(struct depmod *depmod,
-                                   struct vertex *vertex,
-                                   struct kmod_list **roots,
-                                   struct hash *loop_set)
+static int depmod_report_one_cycle(struct depmod *depmod,
+                                  struct vertex *vertex,
+                                  struct kmod_list **roots,
+                                  struct hash *loop_set)
 {
        const char sep[] = " -> ";
        size_t sz;
@@ -1493,6 +1493,7 @@ static void depmod_report_one_cycle(struct depmod *depmod,
        int i;
        int n;
        struct vertex *v;
+       int rc;
 
        array_init(&reverse, 3);
 
@@ -1503,7 +1504,10 @@ static void depmod_report_one_cycle(struct depmod *depmod,
 
                sz += v->mod->modnamesz - 1;
                array_append(&reverse, v);
-               hash_add(loop_set, v->mod->modname, NULL);
+               rc = hash_add(loop_set, v->mod->modname, NULL);
+               if (rc != 0)
+                       return rc;
+               /* the hash will be freed where created */
        }
        sz += vertex->mod->modnamesz - 1;
 
@@ -1528,6 +1532,8 @@ static void depmod_report_one_cycle(struct depmod *depmod,
 
        free(buf);
        array_free_array(&reverse);
+
+       return 0;
 }
 
 static int depmod_report_cycles_from_root(struct depmod *depmod,
@@ -1545,17 +1551,18 @@ static int depmod_report_cycles_from_root(struct depmod *depmod,
        struct mod *m;
        struct mod **itr, **itr_end;
        size_t is;
+       int ret = -ENOMEM;
 
        root = vertex_new(root_mod, NULL);
        if (root == NULL) {
                ERR("No memory to report cycles\n");
-               return -ENOMEM;
+               goto out;
        }
 
        l = kmod_list_append(free_list, root);
        if (l == NULL) {
                ERR("No memory to report cycles\n");
-               return -ENOMEM;
+               goto out;
        }
        free_list = l;
 
@@ -1570,8 +1577,13 @@ static int depmod_report_cycles_from_root(struct depmod *depmod,
                 * from part of a loop or from a branch after a loop
                 */
                if (m->visited && m == root->mod) {
-                       depmod_report_one_cycle(depmod, vertex,
-                                               roots, loop_set);
+                       int rc;
+                       rc = depmod_report_one_cycle(depmod, vertex,
+                                                    roots, loop_set);
+                       if (rc != 0) {
+                               ret = rc;
+                               goto out;
+                       }
                        continue;
                }
 
@@ -1598,7 +1610,7 @@ static int depmod_report_cycles_from_root(struct depmod *depmod,
                        v = vertex_new(dep, vertex);
                        if (v == NULL) {
                                ERR("No memory to report cycles\n");
-                               return -ENOMEM;
+                               goto out;
                        }
                        assert(is < stack_size);
                        stack[is++] = v;
@@ -1606,12 +1618,15 @@ static int depmod_report_cycles_from_root(struct depmod *depmod,
                        l = kmod_list_append(free_list, v);
                        if (l == NULL) {
                                ERR("No memory to report cycles\n");
-                               return -ENOMEM;
+                               goto out;
                        }
                        free_list = l;
 
                }
        }
+       ret = 0;
+
+out:
        while (free_list) {
                v = free_list->data;
                l = kmod_list_remove(free_list);
@@ -1619,7 +1634,7 @@ static int depmod_report_cycles_from_root(struct depmod *depmod,
                free(v);
        }
 
-       return 0;
+       return ret;
 }
 
 static void depmod_report_cycles(struct depmod *depmod, uint16_t n_mods,
@@ -1643,7 +1658,7 @@ static void depmod_report_cycles(struct depmod *depmod, uint16_t n_mods,
                l = kmod_list_append(roots, m);
                if (l == NULL) {
                        ERR("No memory to report cycles\n");
-                       return;
+                       goto out_list;
                }
                roots = l;
                n_r++;
@@ -1652,13 +1667,13 @@ static void depmod_report_cycles(struct depmod *depmod, uint16_t n_mods,
        stack = malloc(n_r * sizeof(void *));
        if (stack == NULL) {
                ERR("No memory to report cycles\n");
-               return;
+               goto out_list;
        }
 
        loop_set = hash_new(16, NULL);
        if (loop_set == NULL) {
                ERR("No memory to report cycles\n");
-               return;
+               goto out_list;
        }
 
        while (roots != NULL) {
@@ -1670,14 +1685,19 @@ static void depmod_report_cycles(struct depmod *depmod, uint16_t n_mods,
                                                     &roots,
                                                     stack, n_r, loop_set);
                if (err < 0)
-                       goto err;
+                       goto out_hash;
        }
 
        num_cyclic = hash_get_count(loop_set);
        ERR("Found %d modules in dependency cycles!\n", num_cyclic);
 
-err:
+out_hash:
        hash_free(loop_set);
+out_list:
+       while (roots != NULL) {
+               /* no need to free data, come from outside */
+               roots = kmod_list_remove(roots);
+       }
 }
 
 static int depmod_calculate_dependencies(struct depmod *depmod)