CVE-2026-80887drm/vmwgfx: use check_add_overflow for shader size+offset bound

Official 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.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/1bbe7751f5ebac383405ef29a66622d65bd505d3
• https://git.kernel.org/stable/c/d3f44438aa805270aaead3b6840ccaea0f4c11f9
• https://git.kernel.org/stable/c/cfd163169af3be56eaef113c680ea251f0d09189
• https://git.kernel.org/stable/c/5c725901908eb1e52a16fc0e2373cb761df42d21
• https://git.kernel.org/stable/c/54d56d5b42d2e4c72ba6e365e9774da90698aa22