diff options
| author | Zack Rusin <zack.rusin@broadcom.com> | 2026-05-05 18:22:32 -0400 |
|---|---|---|
| committer | Zack Rusin <zack.rusin@broadcom.com> | 2026-07-27 11:29:24 -0400 |
| commit | 54d56d5b42d2e4c72ba6e365e9774da90698aa22 (patch) | |
| tree | b6110448d1ec5cdcdd48719369760d427571b048 /drivers/gpu | |
| parent | e5c3e484e0d84744a9bd9349469cd41dc8666a2f (diff) | |
drm/vmwgfx: use check_add_overflow for shader size+offset bound
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: 668b206601c5 ("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
Diffstat (limited to 'drivers/gpu')
| -rw-r--r-- | drivers/gpu/drm/vmwgfx/vmwgfx_shader.c | 13 |
1 files changed, 9 insertions, 4 deletions
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_shader.c b/drivers/gpu/drm/vmwgfx/vmwgfx_shader.c index eca4e3e97eb4..39811cf19db1 100644 --- a/drivers/gpu/drm/vmwgfx/vmwgfx_shader.c +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_shader.c @@ -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 @@ out: 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 @@ out_err: 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; |