CVE-2026-43368 drm/i915: Fix potential overflow of shmem scatterlist length
An integer overflow in the i915 driver can cause premature termination of memory mapping, leading to denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-43368?
CVE-2026-43368 is a high-severity vulnerability in Linux kernel, published on 8 May 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
drm/i915: Fix potential overflow of shmem scatterlist length
When a scatterlists table of a GEM shmem object of size 4 GB or more is populated with pages allocated from a folio, unsigned int .length attribute of a scatterlist may get overflowed if total byte length of pages allocated to that single scatterlist happens to reach or cross the 4GB limit. As a consequence, users of the object may suffer from hitting unexpected, premature end of the object's backing pages.
[278.780187] ------------[ cut here ]------------ [278.780377] WARNING: CPU: 1 PID: 2326 at drivers/gpu/drm/i915/i915_mm.c:55 remap_sg+0x199/0x1d0 [i915] ... [278.780654] CPU: 1 UID: 0 PID: 2326 Comm: gem_mmap_offset Tainted: G S U 6.17.0-rc1-CI_DRM_16981-ged823aaa0607+ #1 PREEMPT(voluntary) [278.780656] Tainted: [S]=CPU_OUT_OF_SPEC, [U]=USER [278.780658] Hardware name: Intel Corporation Meteor Lake Client Platform/MTL-P LP5x T3 RVP, BIOS MTLPFWI1.R00.3471.D91.2401310918 01/31/2024 [278.780659] RIP: 0010:remap_sg+0x199/0x1d0 [i915] ... [278.780786] Call Trace: [278.780787] <TASK> [278.780788] ? __apply_to_page_range+0x3e6/0x910 [278.780795] ? __pfx_remap_sg+0x10/0x10 [i915] [278.780906] apply_to_page_range+0x14/0x30 [278.780908] remap_io_sg+0x14d/0x260 [i915] [278.781013] vm_fault_cpu+0xd2/0x330 [i915] [278.781137] __do_fault+0x3a/0x1b0 [278.781140] do_fault+0x322/0x640 [278.781143] __handle_mm_fault+0x938/0xfd0 [278.781150] handle_mm_fault+0x12c/0x300 [278.781152] ? lock_mm_and_find_vma+0x4b/0x760 [278.781155] do_user_addr_fault+0x2d6/0x8e0 [278.781160] exc_page_fault+0x96/0x2c0 [278.781165] asm_exc_page_fault+0x27/0x30 ...
That issue was apprehended by the author of a change that introduced it, and potential risk even annotated with a comment, but then never addressed.
When adding folio pages to a scatterlist table, take care of byte length of any single scatterlist not exceeding max_segment.
(cherry picked from commit 06249b4e691a75694c014a61708c007fb5755f60)
Weakness: CWE-190
Which versions are affected by CVE-2026-43368?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-43368?
Apply the vendor's patch.
Is CVE-2026-43368 being exploited?
There is no known exploitation of CVE-2026-43368 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-43368, DEBIAN-CVE-2026-43368, GHSA-rm7m-cqfw-43rf, ROOT-OS-UBUNTU-2404-CVE-2026-43368, UBUNTU-CVE-2026-43368.