Description
In the Linux kernel, the following vulnerability has been resolved:
drm/vmwgfx: validate external BO copy bounds for both stride paths
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.
drm/vmwgfx: validate external BO copy bounds for both stride paths
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.
Published:
2026-08-28
Score:
n/a
EPSS:
n/a
KEV:
No
Impact:
n/a
Action:
n/a
Analysis
Analysis and contextual insights are available on OpenCVE Cloud.
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||||||||||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Linux | Linux | unaffected |
|
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| Linux | Linux | affected |
|
No data.
No data.
No data available yet.
Remediation
No vendor fix or workaround currently provided.
Additional remediation guidance may be available on OpenCVE Cloud.
Tracking
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Advisories
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References
History
Fri, 28 Aug 2026 07:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | In the Linux kernel, the following vulnerability has been resolved: drm/vmwgfx: validate external BO copy bounds for both stride paths 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. | |
| Title | drm/vmwgfx: validate external BO copy bounds for both stride paths | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
|
MITRE
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-08-28T06:53:04.050Z
Reserved: 2026-08-26T14:34:25.786Z
Link: CVE-2026-80700
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-08-28T08:16:55.517
Modified: 2026-08-28T08:16:55.517
Link: CVE-2026-80700
Redhat
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.