Re: [PATCH] 2.6.6 memory allocation checks in SliceBlock()

["Randy.Dunlap" <rddunlap@osdl.org>]

On Sun, 06 Jun 2004 19:23:12 +0300 Yury Umanets wrote:

| Adds memory allocation checks in SliceBlock()
| 
|  ./linux-2.6.6-modified/drivers/char/drm/sis_ds.c |    4 ++++
|  1 files changed, 4 insertions(+)
| 
| Signed-off-by: Yury Umanets <torque@ukrpost.net>
| 
| diff -rupN ./linux-2.6.6/drivers/char/drm/sis_ds.c
| ./linux-2.6.6-modified/drivers/char/drm/sis_ds.c
| --- ./linux-2.6.6/drivers/char/drm/sis_ds.c	Mon May 10 05:33:19 2004
| +++ ./linux-2.6.6-modified/drivers/char/drm/sis_ds.c	Wed Jun  2 14:19:22
| 2004
| @@ -231,6 +231,8 @@ static TMemBlock* SliceBlock(TMemBlock *
|  	if (startofs > p->ofs) {
|  		newblock = (TMemBlock*) DRM(calloc)(1, sizeof(TMemBlock),
|  		    DRM_MEM_DRIVER);
| +		if (!newblock)
| +			return NULL;
|  		newblock->ofs = startofs;
|  		newblock->size = p->size - (startofs - p->ofs);
|  		newblock->free = 1;
| @@ -244,6 +246,8 @@ static TMemBlock* SliceBlock(TMemBlock *
|  	if (size < p->size) {
|  		newblock = (TMemBlock*) DRM(calloc)(1, sizeof(TMemBlock),
|  		    DRM_MEM_DRIVER);
| +		if (!newblock)
| +			return NULL;
|  		newblock->ofs = startofs + size;
|  		newblock->size = p->size - size;
|  		newblock->free = 1;
| 
| -- 

These look like the right thing to do, but one caller of
SliceBlock() has no error handling:

mmAllocMem():

	p = SliceBlock(p,startofs,size,0,mask+1);
	p->heap = heap;
	return p;

However, callers of mmAllocMem() do have failure handling.

--
~Randy