From: Szabolcs Nagy <nsz@port70.net>
Date: Sun, 31 Jan 2016 16:31:03 +0000 (+0100)
Subject: fix malloc_usable_size for NULL input
X-Git-Tag: v1.1.13~11
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=d1507646975cbf6c3e511ba07b193f27f032d108;p=oweals%2Fmusl.git

fix malloc_usable_size for NULL input

the linux man page specifies malloc_usable_size(0) to return 0 and
this is the semantics other implementations follow (jemalloc).
reported by Alexander Monakov.
---

diff --git a/src/malloc/malloc_usable_size.c b/src/malloc/malloc_usable_size.c
index 8cccd9d8..6743ea77 100644
--- a/src/malloc/malloc_usable_size.c
+++ b/src/malloc/malloc_usable_size.c
@@ -13,5 +13,5 @@ struct chunk {
 
 size_t malloc_usable_size(void *p)
 {
-	return CHUNK_SIZE(MEM_TO_CHUNK(p)) - OVERHEAD;
+	return p ? CHUNK_SIZE(MEM_TO_CHUNK(p)) - OVERHEAD : 0;
 }