CVE-2026-80887
🔶 mediumSummary
In the Linux kernel, the following vulnerability has been resolved: 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_off
Description
In the Linux kernel, the following vulnerability has been resolved:
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.