BUG/MINOR: hlua: Fix memory leaks on error path when registering a cli keyword

When an error occurred in hlua_register_cli(), the allocated lua function
and keyword must be released to avoid memory leaks.

This patch depends on "MINOR: hlua: Add function to release a lua
function". It may be backported in all stable versions.

diff --git a/src/hlua.c b/src/hlua.c
index d70050352b7f3fb68bea34dd1fdb721982906a43..5a67f02d19e72f5e5cb6df1c28cf6de42e08b627 100644 (file)
--- a/src/hlua.c
+++ b/src/hlua.c
@@ -8116,12 +8116,13 @@ __LJMP static int hlua_register_cli(lua_State *L)
        const char *message;
        int ref_io;
        int len;
-       struct hlua_function *fcn;
+       struct hlua_function *fcn = NULL;
        int index;
        int i;
        struct buffer *trash;
        const char *kw[5];
        struct cli_kw *cli_kw;
+       const char *errmsg;
 
        MAY_LJMP(check_args(L, 3, "register_cli"));
 
@@ -8166,39 +8167,53 @@ __LJMP static int hlua_register_cli(lua_State *L)
 
        /* Allocate and fill the sample fetch keyword struct. */
        cli_kws = calloc(1, sizeof(*cli_kws) + sizeof(struct cli_kw) * 2);
-       if (!cli_kws)
-               WILL_LJMP(luaL_error(L, "Lua out of memory error."));
+       if (!cli_kws) {
+               errmsg = "Lua out of memory error.";
+               goto error;
+       }
        fcn = new_hlua_function();
-       if (!fcn)
-               WILL_LJMP(luaL_error(L, "Lua out of memory error."));
+       if (!fcn) {
+               errmsg = "Lua out of memory error.";
+               goto error;
+       }
 
        /* Fill path. */
        index = 0;
        lua_pushnil(L);
        while(lua_next(L, 1) != 0) {
-               if (index >= 5)
-                       WILL_LJMP(luaL_argerror(L, 1, "1st argument must be a table with a maximum of 5 entries"));
-               if (lua_type(L, -1) != LUA_TSTRING)
-                       WILL_LJMP(luaL_argerror(L, 1, "1st argument must be a table filled with strings"));
+               if (index >= 5) {
+                       errmsg = "1st argument must be a table with a maximum of 5 entries";
+                       goto error;
+               }
+               if (lua_type(L, -1) != LUA_TSTRING) {
+                       errmsg = "1st argument must be a table filled with strings";
+                       goto error;
+               }
                cli_kws->kw[0].str_kw[index] = strdup(lua_tostring(L, -1));
-               if (!cli_kws->kw[0].str_kw[index])
-                       WILL_LJMP(luaL_error(L, "Lua out of memory error."));
+               if (!cli_kws->kw[0].str_kw[index]) {
+                       errmsg = "Lua out of memory error.";
+                       goto error;
+               }
                index++;
                lua_pop(L, 1);
        }
 
        /* Copy help message. */
        cli_kws->kw[0].usage = strdup(message);
-       if (!cli_kws->kw[0].usage)
-               WILL_LJMP(luaL_error(L, "Lua out of memory error."));
+       if (!cli_kws->kw[0].usage) {
+               errmsg = "Lua out of memory error.";
+               goto error;
+       }
 
        /* Fill fcn io handler. */
        len = strlen("<lua.cli>") + 1;
        for (i = 0; i < index; i++)
                len += strlen(cli_kws->kw[0].str_kw[i]) + 1;
        fcn->name = calloc(1, len);
-       if (!fcn->name)
-               WILL_LJMP(luaL_error(L, "Lua out of memory error."));
+       if (!fcn->name) {
+               errmsg = "Lua out of memory error.";
+               goto error;
+       }
        strncat((char *)fcn->name, "<lua.cli", len);
        for (i = 0; i < index; i++) {
                strncat((char *)fcn->name, ".", len);
@@ -8217,6 +8232,17 @@ __LJMP static int hlua_register_cli(lua_State *L)
        cli_register_kw(cli_kws);
 
        return 0;
+
+  error:
+       release_hlua_function(fcn);
+       if (cli_kws) {
+               for (i = 0; i < index; i++)
+                       ha_free((char **)&(cli_kws->kw[0].str_kw[i]));
+               ha_free((char **)&(cli_kws->kw[0].usage));
+       }
+       ha_free(&cli_kws);
+       WILL_LJMP(luaL_error(L, errmsg));
+       return 0; /* Never reached */
 }
 
 static int hlua_read_timeout(char **args, int section_type, struct proxy *curpx,