kernel/linux.git/drivers/gpu/drm/vmwgfx, branch v7.1.12

drm/vmwgfx: validate external BO copy bounds for both stride paths

2026-08-09T18:26:56+00:00

commit 706c93c5813caabbb0d0a576c017d15aeec2c113 upstream. vmw_external_bo_copy() trusts caller-supplied offsets, strides, and heights and operates on imported dma-buf vmaps: - The equal-stride memcpy() bound was clamped after subtracting the offsets from dst_size and src_size; an offset larger than the BO size wraps the unsigned subtraction to a huge value and the resulting memcpy() runs off the end of the vmap. dst_stride * height is also a u32 multiplication that can overflow. - The non-equal-stride row-by-row path had no bound at all. The loop touches bytes through offset + (height - 1) * stride + width_in_bytes, with only a WARN_ON(dst_stride < width_in_bytes), and could likewise step past the end of either mapping. The offsets and strides are derived from STDU/SOU plane state, so a configured CRTC submitting a crafted atomic commit on an imported framebuffer can reach this path. Validate the exact row-copy endpoint against each BO's size up front using check_mul_overflow() and check_add_overflow(). Use the bulk memcpy() path only when width_in_bytes covers the whole stride; otherwise copy one row at a time so partial-row updates near the bottom of a framebuffer remain valid. Also reject zero strides and stride < width_in_bytes, both of which the row-by-row path cannot represent safely. Fixes: 50f119925091 ("drm/vmwgfx: Fix prime with external buffers") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4.7 Signed-off-by: Zack Rusin Reviewed-by: Ian Forbes Link: https://patch.msgid.link/20260505222728.519626-13-zack.rusin@broadcom.com Signed-off-by: Greg Kroah-Hartman

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

2026-08-09T18:26:56+00:00

commit 54d56d5b42d2e4c72ba6e365e9774da90698aa22 upstream. 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 Reviewed-by: Ian Forbes Link: https://patch.msgid.link/20260505222728.519626-12-zack.rusin@broadcom.com Signed-off-by: Greg Kroah-Hartman

drm/vmwgfx: enforce cursor size limits for MOB cursors

2026-08-09T18:26:56+00:00

commit d5ed8749168ad13c0dbaa8300f68d854b6076966 upstream. vmw_cursor_plane_atomic_check() bounds cursor width and height only on the legacy update path; the SVGA_CAP2_CURSOR_MOB path -- the default on modern hosts -- accepts any size. When the requested size exceeds SVGA_REG_CURSOR_MAX_DIMENSION or SVGA_REG_MOB_MAX_SIZE, vmw_cursor_mob_get() returns -EINVAL and leaves vps->cursor.mob NULL. Its return value is then discarded in vmw_cursor_plane_prepare_fb(), so the subsequent vmw_cursor_update_mob() calls vmw_bo_map_and_cache(NULL) and oopses inside vmw_bo_map_and_cache_size() on the tbo.base.size load. Reachable from any DRM master via DRM_IOCTL_MODE_CURSOR2 with a sufficiently large width or height (e.g. cursor_max_dim + 1). Reject oversized cursors in atomic_check for both MOB-backed cursor update types. The MOB byte-size limit only applies to the SVGA_CAP2_CURSOR_MOB path (vmw_cursor_mob_size() returns 0 for GB_ONLY); compute the required MOB size in 64-bit to avoid overflow when very large dimensions are requested. In prepare_fb only call vmw_cursor_mob_get()/_map() for VMW_CURSOR_UPDATE_MOB -- the GB_ONLY path uses bo->map.virtual directly and would otherwise be silently downgraded to NONE on hosts without SVGA_CAP2_CURSOR_MOB (where vmw_cursor_mob_get() always returns -EINVAL). Degrade the update to NONE if vmw_cursor_mob_get() or vmw_cursor_mob_map() fails so the update path does not run with a NULL backing MOB. Fixes: 965544150d1c ("drm/vmwgfx: Refactor cursor handling") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4.7 Signed-off-by: Zack Rusin Reviewed-by: Ian Forbes Link: https://patch.msgid.link/20260505222728.519626-10-zack.rusin@broadcom.com Signed-off-by: Greg Kroah-Hartman

drm/vmwgfx: avoid destroy_workqueue(NULL) on vkms init failure

2026-08-09T18:26:56+00:00

commit 05eaa887e7b4f40fba425f8a1d7a5a8a043092a6 upstream. Two paths through vmw_vkms_init() can leave vmw->crc_workq NULL while still leaving the rest of the driver in a state that calls vmw_vkms_cleanup() at module unload: 1. vmw_host_get_guestinfo(GUESTINFO_VBLANK, ...) failing or returning an oversized buffer -- the common case on hosts without a VBLANK guestinfo entry -- early-returned before the workqueue allocation. 2. alloc_ordered_workqueue() returning NULL on memory pressure. vmw_vkms_cleanup() then calls destroy_workqueue(NULL), which dereferences wq->name and panics. Fix the first case by removing the early return: vmw->vkms_enabled is already false on the rpci-failure path so no work will ever be queued, and allocating the workqueue unconditionally keeps the control flow simple. Fix the second case by guarding the cleanup with a NULL check, since alloc_ordered_workqueue() can still fail under low memory. Fixes: 7b0062036c3b ("drm/vmwgfx: Implement virtual crc generation") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4.7 Signed-off-by: Zack Rusin Reviewed-by: Ian Forbes Link: https://patch.msgid.link/20260505222728.519626-9-zack.rusin@broadcom.com Signed-off-by: Greg Kroah-Hartman

drm/vmwgfx: bound DMA command body size against suffix pointer

2026-08-09T18:26:56+00:00

commit f4f1db96bfd68b81053693ba53405b6f510ac16c upstream. vmw_cmd_dma() locates the DMA suffix at (unsigned long) &cmd->body + header->size - sizeof(*suffix) without checking that header->size is large enough to contain both cmd->body and the suffix. An undersized header makes the suffix pointer underflow back into the previous command in the bounce buffer. The verifier later writes suffix->maximumOffset, clobbering verified fields of an already-relocated earlier command -- a TOCTOU on the device-visible command stream that lets one command rewrite another's GMR id, surface id, or other authenticated fields. Reject the command if the body is too small for the suffix to fit. Fixes: 4e4ddd477743 ("drm/vmwgfx: Fix queries if no dma buffer thrashing is occuring.") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4.7 Signed-off-by: Zack Rusin Reviewed-by: Ian Forbes Link: https://patch.msgid.link/20260505222728.519626-8-zack.rusin@broadcom.com Signed-off-by: Greg Kroah-Hartman

drm/vmwgfx: validate DRAW_PRIMITIVES header size before division

2026-08-09T18:26:56+00:00

commit 85891d174707d8bddcec7a888fb4e1d17def34f3 upstream. vmw_cmd_draw() computes maxnum = (header->size - sizeof(cmd->body)) / sizeof(*decl); where header->size is u32 and is taken straight from the user-supplied command stream. When header->size is less than sizeof(cmd->body) the unsigned subtraction wraps to nearly 4 GiB, producing a huge maxnum. Any user-controlled cmd->body.numVertexDecls then passes the bound and the loop dereferences decl[i] far past the end of the kernel command bounce buffer, producing an out-of-bounds read of kernel memory. Reject undersized headers up front. Fixes: 7a73ba7469cb ("drm/vmwgfx: Use TTM handles instead of SIDs as user-space surface handles.") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4.7 Signed-off-by: Zack Rusin Reviewed-by: Ian Forbes Link: https://patch.msgid.link/20260505222728.519626-7-zack.rusin@broadcom.com Signed-off-by: Greg Kroah-Hartman

drm/vmwgfx: drop dma_buf reference on foreign-fd prime import

2026-08-09T18:26:56+00:00

commit f739416dc555fa205a785e5135d73fa39b26f35d upstream. ttm_prime_fd_to_handle() returns -ENOSYS when the imported fd's dma_buf->ops do not match the ttm_object_device's ops, but does so without releasing the reference acquired by dma_buf_get(). Any unprivileged renderD client passing a non-vmwgfx prime fd through the DRM_VMW_GB_SURFACE_REF{,_EXT} path leaks one dma_buf reference per call and indefinitely pins the foreign exporter's GEM resources. Funnel the error path through the existing dma_buf_put() so the reference is always dropped. Fixes: 65981f7681ab ("drm/ttm: Add a minimal prime implementation for ttm base objects") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4.7 Signed-off-by: Zack Rusin Reviewed-by: Ian Forbes Link: https://patch.msgid.link/20260505222728.519626-6-zack.rusin@broadcom.com Signed-off-by: Greg Kroah-Hartman

drm/vmwgfx: take fman->lock around fence list mutation in fifo_down

2026-08-09T18:26:56+00:00

commit 250af2e8c3e90dc978e062a936b633870a22e660 upstream. vmw_fence_fifo_down() drops fman->lock to wait on a fence and, on timeout, mutates fman->fence_list via list_del_init() and signals the fence without re-acquiring the lock. __vmw_fences_update() walks and removes entries from the same list under fman->lock from any other waiter, the fence-IRQ thread, or vmw_fences_update(), so the unlocked list_del_init() can corrupt the list head. Re-take fman->lock before manipulating fence->head and use dma_fence_signal_locked(). Wrap the locked signalling in dma_fence_begin_signalling() / dma_fence_end_signalling() so the lockdep annotation that dma_fence_signal() previously provided is preserved (the same pattern as __vmw_fences_update()). dma_fence_put() is moved outside the lock to avoid a recursive acquire from vmw_fence_obj_destroy(), which also takes fman->lock. Fixes: ae2a104058e2 ("vmwgfx: Implement fence objects") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4.7 Signed-off-by: Zack Rusin Reviewed-by: Ian Forbes Link: https://patch.msgid.link/20260505222728.519626-5-zack.rusin@broadcom.com Signed-off-by: Greg Kroah-Hartman

drm/vmwgfx: clamp dirty-page range with min, not max

2026-08-09T18:26:55+00:00

commit f47d542d5912f236273399d7139b522f6950e2e4 upstream. vmw_bo_dirty_transfer_to_res() and vmw_bo_dirty_clear() compute the intersection of a resource's page range with the BO's tracked dirty range, but clamp res_end against dirty->end with max() instead of min(). When dirty->end exceeds the resource end, the loop walks past the resource's pages, calls vmw_resource_dirty_update() for ranges owned by other resources sharing the same backing MOB and clears their pending dirty bits via bitmap_clear(). The result is silent loss of writeback for unrelated resources whenever two resources share a MOB. Use min() in both functions so the loop is bounded to the intersection of the resource and dirty ranges. Fixes: b7468b15d271 ("drm/vmwgfx: Implement an infrastructure for write-coherent resources") Fixes: 965544150d1c ("drm/vmwgfx: Refactor cursor handling") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4.7 Signed-off-by: Zack Rusin Reviewed-by: Ian Forbes Link: https://patch.msgid.link/20260505222728.519626-4-zack.rusin@broadcom.com Signed-off-by: Greg Kroah-Hartman

drm/vmwgfx: reject DX_BIND_QUERY without a DX context

2026-08-09T18:26:55+00:00

commit 55ec09c9ce10b1272802c7ab6c1be2ea0dbc68db upstream. vmw_cmd_dx_bind_query() unconditionally dereferences sw_context->dx_ctx_node->ctx. Userspace can trigger a NULL pointer dereference from any render-node fd by submitting an execbuf with dx_context_handle == SVGA3D_INVALID_ID and a SVGA_3D_CMD_DX_BIND_QUERY opcode in the command stream: dx_ctx_node is left NULL and the kernel oopses on the assignment. The same NULL is then re-read in vmw_resources_reserve() via vmw_context_get_dx_query_mob(). All sibling DX handlers fail-close on a missing dx_ctx_node using VMW_GET_CTX_NODE(). Use the same pattern here, returning -EINVAL up front before any relocation state is published. Fixes: 9c079b8ce8bf ("drm/vmwgfx: Adapt execbuf to the new validation api") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4.7 Signed-off-by: Zack Rusin Reviewed-by: Ian Forbes Link: https://patch.msgid.link/20260505222728.519626-3-zack.rusin@broadcom.com Signed-off-by: Greg Kroah-Hartman