From: Dan Kegel <dank@kegel.com>
Date: Sat, 13 Jun 2020 19:17:46 +0000 (+0000)
Subject: infcover.c: assert that we avoid zero-length allocations; fixes #593
X-Git-Tag: 1.9.9-b1~216
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ee28753685d62117f8ef4ef8b94ba101a5cd1e96;p=thirdparty%2Fzlib-ng.git

infcover.c: assert that we avoid zero-length allocations; fixes #593
---

diff --git a/test/infcover.c b/test/infcover.c
index 10baaad5..9f98bd5c 100644
--- a/test/infcover.c
+++ b/test/infcover.c
@@ -242,8 +242,11 @@ static void mem_done(PREFIX3(stream) *strm, char *prefix) {
 static unsigned char *h2b(const char *hex, unsigned *len) {
     unsigned char *in, *re;
     unsigned next, val;
+    unsigned inlen;
 
-    in = malloc((strlen(hex) + 1) >> 1);
+    inlen = (strlen(hex) + 1) >> 1;
+    assert(inlen != 0);     /* tell static analyzer we won't call malloc(0) */
+    in = malloc(inlen);
     if (in == NULL)
         return NULL;
     next = 0;
@@ -264,6 +267,7 @@ static unsigned char *h2b(const char *hex, unsigned *len) {
     } while (*hex++);       /* go through the loop with the terminating null */
     if (len != NULL)
         *len = next;
+    assert(next != 0);      /* tell static analyzer we won't call realloc(in, 0) */
     re = realloc(in, next);
     return re == NULL ? in : re;
 }