kmodloader: improve memory accounting and deallocation

Add missing calls to free module_folders and modules data during cleanup,
and ensure that resources are consistently freed on exit paths.

Signed-off-by: Tony Ambardar <itugrok@yahoo.com>

diff --git a/kmodloader.c b/kmodloader.c
index cad22484e97fbffb4bd267dc43243391fbc90090..12878391d2e54336e1ca595c5b49902106960a95 100644 (file)
--- a/kmodloader.c
+++ b/kmodloader.c
@@ -132,6 +132,17 @@ static int init_module_folders(void)
        return 0;
 }
 
+static void free_module_folders(void)
+{
+       int n = 0;
+
+       if (!module_folders)
+               return;
+       while (module_folders[n])
+               free(module_folders[n++]);
+       free(module_folders);
+}
+
 static struct module *find_module(const char *name)
 {
        struct module_node *mn;
@@ -881,8 +892,8 @@ static int print_usage(char *arg)
 
 static int main_insmod(int argc, char **argv)
 {
-       char *name, *cur, *options;
-       int i, ret, len;
+       char *name, *cur, *options = NULL;
+       int i, ret = -1, len;
 
        if (argc < 2)
                return print_insmod_usage();
@@ -898,19 +909,16 @@ static int main_insmod(int argc, char **argv)
 
        if (find_module(name)) {
                ULOG_ERR("module is already loaded - %s\n", name);
-               return -1;
+               goto err;
 
        }
 
-       free_modules();
-
        for (len = 0, i = 2; i < argc; i++)
                len += strlen(argv[i]) + 1;
 
        options = malloc(len);
        if (!options) {
                ULOG_ERR("out of memory\n");
-               ret = -1;
                goto err;
        }
 
@@ -926,7 +934,6 @@ static int main_insmod(int argc, char **argv)
 
        if (init_module_folders()) {
                fprintf(stderr, "Failed to find the folder holding the modules\n");
-               ret = -1;
                goto err;
        }
 
@@ -934,7 +941,6 @@ static int main_insmod(int argc, char **argv)
                name = argv[1];
        } else if (!get_module_path(name)) {
                fprintf(stderr, "Failed to find %s. Maybe it is a built in module ?\n", name);
-               ret = -1;
                goto err;
        }
 
@@ -944,6 +950,9 @@ static int main_insmod(int argc, char **argv)
 
 err:
        free(options);
+       free_modules();
+       free_module_folders();
+
        return ret;
 }
 
@@ -951,7 +960,7 @@ static int main_rmmod(int argc, char **argv)
 {
        struct module *m;
        char *name;
-       int ret;
+       int ret = -1;
 
        if (argc != 2)
                return print_usage("rmmod");
@@ -966,18 +975,20 @@ static int main_rmmod(int argc, char **argv)
        m = find_module(name);
        if (!m) {
                ULOG_ERR("module is not loaded\n");
-               return -1;
+               goto err;
        }
        if (m->state == BUILTIN) {
                ULOG_ERR("module is builtin\n");
-               return -1;
+               goto err;
        }
        ret = syscall(__NR_delete_module, m->name, 0);
 
        if (ret)
                ULOG_ERR("unloading the module failed\n");
 
+err:
        free_modules();
+       free_module_folders();
 
        return ret;
 }
@@ -1019,6 +1030,7 @@ static int main_lsmod(int argc, char **argv)
 static int main_modinfo(int argc, char **argv)
 {
        struct module *m;
+       int rv = -1;
        char *name;
 
        if (argc != 2)
@@ -1034,12 +1046,17 @@ static int main_modinfo(int argc, char **argv)
        m = find_module(name);
        if (!m) {
                ULOG_ERR("cannot find module - %s\n", argv[1]);
-               return -1;
+               goto err;
        }
 
        print_modinfo(m);
 
-       return 0;
+       rv = 0;
+err:
+       free_modules();
+       free_module_folders();
+
+       return rv;
 }
 
 static int main_modprobe(int argc, char **argv)
@@ -1128,6 +1145,7 @@ static int main_modprobe(int argc, char **argv)
        }
 
        free_modules();
+       free_module_folders();
 
        return exit_code;
 }
@@ -1240,6 +1258,8 @@ static int main_loader(int argc, char **argv)
 
 out:
        globfree(&gl);
+       free_modules();
+       free_module_folders();
 free_path:
        free(path);