lxc-user-nic: use cleanup macros

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>

diff --git a/src/lxc/cmd/lxc_user_nic.c b/src/lxc/cmd/lxc_user_nic.c
index be6b395be9293c512c96e004d7b5397bd8f474fd..b9683c296460d0cc4304a6076e17786871d43748 100644 (file)
--- a/src/lxc/cmd/lxc_user_nic.c
+++ b/src/lxc/cmd/lxc_user_nic.c
@@ -111,10 +111,9 @@ static int open_and_lock(char *path)
 
 static char *get_username(void)
 {
+       __do_free char *buf = NULL;
        struct passwd pwent;
        struct passwd *pwentp = NULL;
-       char *buf;
-       char *username;
        size_t bufsize;
        int ret;
 
@@ -132,14 +131,10 @@ static char *get_username(void)
                        usernic_error("%s", "Could not find matched password record\n");
 
                CMD_SYSERROR("Failed to get username: %u\n", getuid());
-               free(buf);
                return NULL;
        }
 
-       username = strdup(pwent.pw_name);
-       free(buf);
-
-       return username;
+       return strdup(pwent.pw_name);
 }
 
 static void free_groupnames(char **groupnames)
@@ -157,13 +152,13 @@ static void free_groupnames(char **groupnames)
 
 static char **get_groupnames(void)
 {
+       __do_free char *buf = NULL;
+       __do_free gid_t *group_ids = NULL;
        int ngroups;
-       gid_t *group_ids;
        int ret, i;
        char **groupnames;
        struct group grent;
        struct group *grentp = NULL;
-       char *buf;
        size_t bufsize;
 
        ngroups = getgroups(0, NULL);
@@ -182,14 +177,12 @@ static char **get_groupnames(void)
 
        ret = getgroups(ngroups, group_ids);
        if (ret < 0) {
-               free(group_ids);
                CMD_SYSERROR("Failed to get process groups\n");
                return NULL;
        }
 
        groupnames = malloc(sizeof(char *) * (ngroups + 1));
        if (!groupnames) {
-               free(group_ids);
                CMD_SYSERROR("Failed to allocate memory while getting group names\n");
                return NULL;
        }
@@ -202,7 +195,6 @@ static char **get_groupnames(void)
 
        buf = malloc(bufsize);
        if (!buf) {
-               free(group_ids);
                free_groupnames(groupnames);
                CMD_SYSERROR("Failed to allocate memory while getting group names\n");
                return NULL;
@@ -215,8 +207,6 @@ static char **get_groupnames(void)
                                usernic_error("%s", "Could not find matched group record\n");
 
                        CMD_SYSERROR("Failed to get group name: %u\n", group_ids[i]);
-                       free(buf);
-                       free(group_ids);
                        free_groupnames(groupnames);
                        return NULL;
                }
@@ -224,16 +214,11 @@ static char **get_groupnames(void)
                groupnames[i] = strdup(grent.gr_name);
                if (!groupnames[i]) {
                        usernic_error("Failed to copy group name \"%s\"", grent.gr_name);
-                       free(buf);
-                       free(group_ids);
                        free_groupnames(groupnames);
                        return NULL;
                }
        }
 
-       free(buf);
-       free(group_ids);
-
        return groupnames;
 }
 
@@ -321,13 +306,13 @@ static void free_alloted(struct alloted_s **head)
 static int get_alloted(char *me, char *intype, char *link,
                       struct alloted_s **alloted)
 {
+       __do_free char *line = NULL;
+       __do_fclose FILE *fin = NULL;
        int n, ret;
        char name[100], type[100], br[100];
        char **groups;
-       FILE *fin;
        int count = 0;
        size_t len = 0;
-       char *line = NULL;
 
        fin = fopen(LXC_USERNIC_CONF, "r");
        if (!fin) {
@@ -378,8 +363,6 @@ static int get_alloted(char *me, char *intype, char *link,
        }
 
        free_groupnames(groups);
-       fclose(fin);
-       free(line);
 
        /* Now return the total number of nics that this user can create. */
        return count;
@@ -610,12 +593,12 @@ struct entry_line {
 static bool cull_entries(int fd, char *name, char *net_type, char *net_link,
                         char *net_dev, bool *found_nicname)
 {
+       __do_free struct entry_line *entry_lines = NULL;
        int i, ret;
        char *buf, *buf_end, *buf_start;
        struct stat sb;
        int n = 0;
        bool found, keep;
-       struct entry_line *entry_lines = NULL;
 
        ret = fstat(fd, &sb);
        if (ret < 0) {
@@ -641,7 +624,6 @@ static bool cull_entries(int fd, char *name, char *net_type, char *net_link,
 
                newe = realloc(entry_lines, sizeof(*entry_lines) * (n + 1));
                if (!newe) {
-                       free(entry_lines);
                        lxc_strmunmap(buf, sb.st_size);
                        return false;
                }
@@ -672,8 +654,6 @@ static bool cull_entries(int fd, char *name, char *net_type, char *net_link,
                buf_start++;
        }
 
-       free(entry_lines);
-
        ret = ftruncate(fd, buf_start - buf);
        lxc_strmunmap(buf, sb.st_size);
        if (ret < 0)
@@ -706,9 +686,10 @@ static int count_entries(char *buf, off_t len, char *name, char *net_type, char
 static char *get_nic_if_avail(int fd, struct alloted_s *names, int pid,
                              char *intype, char *br, int allowed, char **cnic)
 {
+       __do_free char *newline = NULL;
        int ret;
        size_t slen;
-       char *newline, *owner;
+       char *owner;
        char nicname[IFNAMSIZ];
        struct stat sb;
        struct alloted_s *n;
@@ -795,7 +776,6 @@ static char *get_nic_if_avail(int fd, struct alloted_s *names, int pid,
        slen = strlen(owner) + strlen(intype) + strlen(br) + strlen(nicname) + 4;
        newline = malloc(slen + 1);
        if (!newline) {
-               free(newline);
                CMD_SYSERROR("Failed allocate memory\n");
                return NULL;
        }
@@ -805,7 +785,6 @@ static char *get_nic_if_avail(int fd, struct alloted_s *names, int pid,
                if (lxc_netdev_delete_by_name(nicname) != 0)
                        usernic_error("Error unlinking %s\n", nicname);
 
-               free(newline);
                return NULL;
        }
 
@@ -824,7 +803,6 @@ static char *get_nic_if_avail(int fd, struct alloted_s *names, int pid,
                if (lxc_netdev_delete_by_name(nicname) != 0)
                        usernic_error("Error unlinking %s\n", nicname);
 
-               free(newline);
                return NULL;
        }
 
@@ -832,7 +810,6 @@ static char *get_nic_if_avail(int fd, struct alloted_s *names, int pid,
         * \0 byte! Files are not \0-terminated!
         */
        memmove(buf + sb.st_size, newline, slen);
-       free(newline);
        lxc_strmunmap(buf, sb.st_size + slen);
 
        return strdup(nicname);
@@ -1115,11 +1092,11 @@ do_partial_cleanup:
 
 int main(int argc, char *argv[])
 {
+       __do_free char *me = NULL, *newname = NULL, *nicname = NULL;
        int fd, n, pid, request, ret;
-       char *me, *newname;
        struct user_nic_args args;
        int container_veth_ifidx = -1, host_veth_ifidx = -1, netns_fd = -1;
-       char *cnic = NULL, *nicname = NULL;
+       char *cnic = NULL;
        struct alloted_s *alloted = NULL;
 
        if (argc < 7 || argc > 8) {
@@ -1248,7 +1225,6 @@ int main(int argc, char *argv[])
        }
 
        n = get_alloted(me, args.type, args.link, &alloted);
-       free(me);
 
        if (request == LXC_USERNIC_DELETE) {
                struct alloted_s *it;
@@ -1313,14 +1289,11 @@ int main(int argc, char *argv[])
                if (ret < 0)
                        usernic_error("Failed to delete \"%s\"\n", cnic);
 
-               free(nicname);
                _exit(EXIT_FAILURE);
        }
 
        host_veth_ifidx = if_nametoindex(nicname);
        if (!host_veth_ifidx) {
-               free(newname);
-               free(nicname);
                CMD_SYSERROR("Failed to get netdev index\n");
                _exit(EXIT_FAILURE);
        }
@@ -1330,8 +1303,6 @@ int main(int argc, char *argv[])
         */
        fprintf(stdout, "%s:%d:%s:%d\n", newname, container_veth_ifidx, nicname,
                host_veth_ifidx);
-       free(newname);
-       free(nicname);
 
        fflush(stdout);
        _exit(EXIT_SUCCESS);