libiptc: guard chain index allocation for different malloc implementations

Some libc implementations such as µClibc return NULL on malloc(0).
They are free to do that per C standard.

Signed-off-by: Jan Engelhardt <jengelh@medozas.de>
Signeed-off-by: Patrick McHardy <kaber@trash.net>

diff --git a/libiptc/libiptc.c b/libiptc/libiptc.c
index 13e4c69f9e44ec521eeabbf97b74c4bffe27fad8..544a5b294064d365997aad67af640ea1a087ec02 100644 (file)
--- a/libiptc/libiptc.c
+++ b/libiptc/libiptc.c
@@ -503,7 +503,7 @@ static int iptcc_chain_index_alloc(struct xtc_handle *h)
              array_elems, array_mem);
 
        h->chain_index = malloc(array_mem);
-       if (!h->chain_index) {
+       if (h->chain_index == NULL && array_mem > 0) {
                h->chain_index_sz = 0;
                return -ENOMEM;
        }