commit df23899: [Minor] Avoid 0 size mallocs

[Vsevolod Stakhov]

Author: Vsevolod Stakhov
Date: 2023-09-07 16:00:56 +0100
URL: https://github.com/rspamd/rspamd/commit/df2389900f12cd82d1246490339ef99e62ba13a1 (HEAD -> master)

[Minor] Avoid 0 size mallocs

---
 src/libserver/re_cache.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/src/libserver/re_cache.c b/src/libserver/re_cache.c
index 171c3d31e..6dd06711b 100644
--- a/src/libserver/re_cache.c
+++ b/src/libserver/re_cache.c
@@ -954,17 +954,20 @@ rspamd_re_cache_process_selector(struct rspamd_task *task,
 					lua_rawgeti(L, -1, i + 1);
 
 					txt = lua_check_text_or_string(L, -1);
-					if (txt) {
+					if (txt && txt->len > 0) {
 						sel_data = txt->start;
 						slen = txt->len;
+						(*svec)[i] = g_malloc(slen);
+						memcpy((*svec)[i], sel_data, slen);
 					}
 					else {
+						/* A hack to avoid malloc(0) */
 						sel_data = "";
 						slen = 0;
+						(*svec)[i] = g_malloc(1);
+						memcpy((*svec)[i], sel_data, 1);
 					}
 
-					(*svec)[i] = g_malloc(slen);
-					memcpy((*svec)[i], sel_data, slen);
 					(*lenvec)[i] = slen;
 					lua_pop(L, 1);
 				}