From c5934054f3f3e2174a9897e901409da17c1a296e Mon Sep 17 00:00:00 2001 From: Brian Paul Date: Wed, 30 Oct 2002 19:40:20 +0000 Subject: [PATCH] fix potential bug in _mesa_align_calloc/malloc (Frank van Heesch) --- src/mesa/main/imports.c | 19 +++++++++++++------ 1 file changed, 13 insertions(+), 6 deletions(-) diff --git a/src/mesa/main/imports.c b/src/mesa/main/imports.c index f9c6986..27ba25d 100644 --- a/src/mesa/main/imports.c +++ b/src/mesa/main/imports.c @@ -1,4 +1,4 @@ -/* $Id: imports.c,v 1.22 2002/10/25 21:06:28 brianp Exp $ */ +/* $Id: imports.c,v 1.23 2002/10/30 19:40:20 brianp Exp $ */ /* * Mesa 3-D graphics library @@ -104,9 +104,14 @@ _mesa_align_malloc(size_t bytes, unsigned long alignment) ASSERT( alignment > 0 ); - ptr = (unsigned long) _mesa_malloc( bytes + alignment ); + /* Allocate extra memory to accomodate rounding up the address for + * alignment and to record the real malloc address. + */ + ptr = (unsigned long) _mesa_malloc(bytes + alignment + sizeof(void *)); + if (!ptr) + return NULL; - buf = (ptr + alignment) & ~(unsigned long)(alignment - 1); + buf = (ptr + alignment + sizeof(void *)) & ~(unsigned long)(alignment - 1); *(unsigned long *)(buf - sizeof(void *)) = ptr; #ifdef DEBUG @@ -117,7 +122,7 @@ _mesa_align_malloc(size_t bytes, unsigned long alignment) } #endif - return (void *)buf; + return (void *) buf; } @@ -128,9 +133,11 @@ _mesa_align_calloc(size_t bytes, unsigned long alignment) ASSERT( alignment > 0 ); - ptr = (unsigned long) _mesa_calloc( bytes + alignment ); + ptr = (unsigned long) _mesa_calloc(bytes + alignment + sizeof(void *)); + if (!ptr) + return NULL; - buf = (ptr + alignment) & ~(unsigned long)(alignment - 1); + buf = (ptr + alignment + sizeof(void *)) & ~(unsigned long)(alignment - 1); *(unsigned long *)(buf - sizeof(void *)) = ptr; #ifdef DEBUG -- 2.7.4