github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-09-22 20:54:03 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

drm/vmwgfx: use check_add_overflow for shader size+offset bound

Browse Source 
vmw_shader_define() validates the user-supplied shader window against
its backing buffer with

	(u64)buffer->tbo.base.size < (u64)size + (u64)offset

drm_vmw_shader_create_arg::offset is __u64 in the uapi; when it is
near U64_MAX the unsigned addition wraps and the resulting tiny value
passes the check.  The unbounded offset is then stored in
res->guest_memory_offset and forwarded to host SVGA shader-create
commands.

Use check_add_overflow() to detect the wrap and compare the resulting
endpoint against the buffer size.

Fixes: 668b206601 ("drm/vmwgfx: Stop using raw ttm_buffer_object's")
Cc: stable@vger.kernel.org
Assisted-by: Claude:claude-opus-4.7
Signed-off-by: Zack Rusin <zack.rusin@broadcom.com>
Reviewed-by: Ian Forbes <ian.forbes@broadcom.com>
Link: https://patch.msgid.link/20260505222728.519626-12-zack.rusin@broadcom.com
This commit is contained in:
Zack Rusin 2026-05-05 18:22:32 -04:00
parent e5c3e484e0
commit 54d56d5b42
1 changed files with 9 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
drivers/gpu/drm/vmwgfx/vmwgfx_shader.c
View File

@ -25,6 +25,8 @@
*
**************************************************************************/
#include <linux/overflow.h>
#include <drm/ttm/ttm_placement.h>
#include "vmwgfx_binding.h"
@ -685,7 +687,7 @@ int vmw_shader_destroy_ioctl(struct drm_device *dev, void *data,
static int vmw_user_shader_alloc(struct vmw_private *dev_priv,
struct vmw_bo *buffer,
size_t shader_size,
size_t offset,
u64 offset,
SVGA3dShaderType shader_type,
uint8_t num_input_sig,
uint8_t num_output_sig,
@ -739,7 +741,7 @@ static int vmw_user_shader_alloc(struct vmw_private *dev_priv,
static struct vmw_resource *vmw_shader_alloc(struct vmw_private *dev_priv,
struct vmw_bo *buffer,
size_t shader_size,
size_t offset,
u64 offset,
SVGA3dShaderType shader_type)
{
struct vmw_shader *shader;
@ -768,7 +770,7 @@ static struct vmw_resource *vmw_shader_alloc(struct vmw_private *dev_priv,
static int vmw_shader_define(struct drm_device *dev, struct drm_file *file_priv,
enum drm_vmw_shader_type shader_type_drm,
u32 buffer_handle, size_t size, size_t offset,
u32 buffer_handle, size_t size, u64 offset,
uint8_t num_input_sig, uint8_t num_output_sig,
uint32_t *shader_handle)
{
@ -779,13 +781,16 @@ static int vmw_shader_define(struct drm_device *dev, struct drm_file *file_priv,
int ret;
if (buffer_handle != SVGA3D_INVALID_ID) {
u64 end;
ret = vmw_user_bo_lookup(file_priv, buffer_handle, &buffer);
if (unlikely(ret != 0)) {
VMW_DEBUG_USER("Couldn't find buffer for shader creation.\n");
return ret;
}
if ((u64)buffer->tbo.base.size < (u64)size + (u64)offset) {
if (check_add_overflow((u64)size, (u64)offset, &end) ||
end > buffer->tbo.base.size) {
VMW_DEBUG_USER("Illegal buffer- or shader size.\n");
ret = -EINVAL;
goto out_bad_arg;