From: Marek Vavruša <mvavrusa@cloudflare.com>
Date: Tue, 29 May 2018 02:28:46 +0000 (-0700)
Subject: cache/entry_rr: fixed undefined behavior
X-Git-Tag: v2.4.0~33^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=fcb227b7830bb490ed47c0623748b8890de7b3b8;p=thirdparty%2Fknot-resolver.git

cache/entry_rr: fixed undefined behavior

Pointer arithmetic with 'void *' is undefined, it only works as GNU extension.
---

diff --git a/lib/cache/entry_rr.c b/lib/cache/entry_rr.c
index 3d518009a..2012fedfb 100644
--- a/lib/cache/entry_rr.c
+++ b/lib/cache/entry_rr.c
@@ -21,7 +21,7 @@
 
 #include "lib/cache/impl.h"
 
-int rdataset_dematerialize(const knot_rdataset_t *rds, void * restrict data)
+int rdataset_dematerialize(const knot_rdataset_t *rds, uint8_t * restrict data)
 {
 	//const void *data0 = data;
 	assert(data);
@@ -47,12 +47,12 @@ int rdataset_dematerialize(const knot_rdataset_t *rds, void * restrict data)
 /** Materialize a knot_rdataset_t from cache with given TTL.
  * Return the number of bytes consumed or an error code.
  */
-static int rdataset_materialize(knot_rdataset_t * restrict rds, const void * const data,
-		const void *data_bound, uint32_t ttl, knot_mm_t *pool)
+static int rdataset_materialize(knot_rdataset_t * restrict rds, const uint8_t * const data,
+		const uint8_t *data_bound, uint32_t ttl, knot_mm_t *pool)
 {
 	assert(rds && data && data_bound && data_bound > data && !rds->data);
 	assert(pool); /* not required, but that's our current usage; guard leaks */
-	const void *d = data; /* iterates over the cache data */
+	const uint8_t *d = data; /* iterates over the cache data */
 	{
 		uint16_t rr_count;
 		memcpy(&rr_count, d, sizeof(rr_count));
diff --git a/lib/cache/impl.h b/lib/cache/impl.h
index 9b0003430..8faf74c06 100644
--- a/lib/cache/impl.h
+++ b/lib/cache/impl.h
@@ -168,7 +168,7 @@ static inline int rdataset_dematerialize_size(const knot_rdataset_t *rds)
 }
 
 /** Dematerialize a rdataset. */
-int rdataset_dematerialize(const knot_rdataset_t *rds, void * restrict data);
+int rdataset_dematerialize(const knot_rdataset_t *rds, uint8_t * restrict data);
 
 /** Partially constructed answer when gathering RRsets from cache. */
 struct answer {