UBUNTU-CVE-2026-43237

Advisory lineage Upstream: 1 Downstream: 0
Upstream
Published: 06 May 2026, 12:16
Last modified:16 Jul 2026, 20:58

Vulnerability Summary

Overall Risk (default)
medium
31/100
CVSS Score
7.8 HIGH
3.1 (osv_ubuntu)
EPSS Score
No data
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

06 May 2026, 12:16
Published
Vulnerability first disclosed
16 Jul 2026, 20:58
Last Modified
Vulnerability information updated

Description

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: Refactor amdgpu_gem_va_ioctl for Handling Last Fence Update and Timeline Management v4 This commit simplifies the amdgpu_gem_va_ioctl function, key updates include: - Moved the logic for managing the last update fence directly into amdgpu_gem_va_update_vm. - Introduced checks for the timeline point to enable conditional replacement or addition of fences. v2: Addressed review comments from Christian. v3: Updated comments (Christian). v4: The previous version selected the fence too early and did not manage its reference correctly, which could lead to stale or freed fences being used. This resulted in refcount underflows and could crash when updating GPU timelines. The fence is now chosen only after the VA mapping work is completed, and its reference is taken safely. After exporting it to the VM timeline syncobj, the driver always drops its local fence reference, ensuring balanced refcounting and avoiding use-after-free on dma_fence. Crash signature: [ 205.828135] refcount_t: underflow; use-after-free. [ 205.832963] WARNING: CPU: 30 PID: 7274 at lib/refcount.c:28 refcount_warn_saturate+0xbe/0x110 ... [ 206.074014] Call Trace: [ 206.076488] <TASK> [ 206.078608] amdgpu_gem_va_ioctl+0x6ea/0x740 [amdgpu] [ 206.084040] ? __pfx_amdgpu_gem_va_ioctl+0x10/0x10 [amdgpu] [ 206.089994] drm_ioctl_kernel+0x86/0xe0 [drm] [ 206.094415] drm_ioctl+0x26e/0x520 [drm] [ 206.098424] ? __pfx_amdgpu_gem_va_ioctl+0x10/0x10 [amdgpu] [ 206.104402] amdgpu_drm_ioctl+0x4b/0x80 [amdgpu] [ 206.109387] __x64_sys_ioctl+0x96/0xe0 [ 206.113156] do_syscall_64+0x66/0x2d0 ... [ 206.553351] BUG: unable to handle page fault for address: ffffffffc0dfde90 ... [ 206.553378] RIP: 0010:dma_fence_signal_timestamp_locked+0x39/0xe0 ... [ 206.553405] Call Trace: [ 206.553409] <IRQ> [ 206.553415] ? __pfx_drm_sched_fence_free_rcu+0x10/0x10 [gpu_sched] [ 206.553424] dma_fence_signal+0x30/0x60 [ 206.553427] drm_sched_job_done.isra.0+0x123/0x150 [gpu_sched] [ 206.553434] dma_fence_signal_timestamp_locked+0x6e/0xe0 [ 206.553437] dma_fence_signal+0x30/0x60 [ 206.553441] amdgpu_fence_process+0xd8/0x150 [amdgpu] [ 206.553854] sdma_v4_0_process_trap_irq+0x97/0xb0 [amdgpu] [ 206.554353] edac_mce_amd(E) ee1004(E) [ 206.554270] amdgpu_irq_dispatch+0x150/0x230 [amdgpu] [ 206.554702] amdgpu_ih_process+0x6a/0x180 [amdgpu] [ 206.555101] amdgpu_irq_handler+0x23/0x60 [amdgpu] [ 206.555500] __handle_irq_event_percpu+0x4a/0x1c0 [ 206.555506] handle_irq_event+0x38/0x80 [ 206.555509] handle_edge_irq+0x92/0x1e0 [ 206.555513] __common_interrupt+0x3e/0xb0 [ 206.555519] common_interrupt+0x80/0xa0 [ 206.555525] </IRQ> [ 206.555527] <TASK> ... [ 206.555650] RIP: 0010:dma_fence_signal_timestamp_locked+0x39/0xe0 ... [ 206.555667] Kernel panic - not syncing: Fatal exception in interrupt

CVSS Metrics

  • v4.0HIGHScore: 7.3CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
  • v3.1HIGHScore: 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected Systems

  • ubuntulinux

    all | all | all | all

  • ubuntulinux-allwinner-5.19

    all

  • ubuntulinux-aws

    all | all | all | all

  • ubuntulinux-aws-5.0

    all

  • ubuntulinux-aws-5.11

    all

  • ubuntulinux-aws-5.13

    all

  • ubuntulinux-aws-5.15

    all

  • ubuntulinux-aws-5.19

    all

  • ubuntulinux-aws-5.3

    all

  • ubuntulinux-aws-5.4

    all

  • ubuntulinux-aws-5.8

    all

  • ubuntulinux-aws-6.14

    all

  • ubuntulinux-aws-6.17

    all

  • ubuntulinux-aws-6.2

    all

  • ubuntulinux-aws-6.5

    all

  • ubuntulinux-aws-6.8

    all

  • ubuntulinux-aws-fips

    all

  • ubuntulinux-aws-hwe

    all

  • ubuntulinux-azure

    all | all | all | all | all

  • ubuntulinux-azure-4.15

    all

  • ubuntulinux-azure-5.11

    all

  • ubuntulinux-azure-5.13

    all

  • ubuntulinux-azure-5.15

    all

  • ubuntulinux-azure-5.19

    all

  • ubuntulinux-azure-5.3

    all

  • ubuntulinux-azure-5.4

    all

  • ubuntulinux-azure-5.8

    all

  • ubuntulinux-azure-6.11

    all

  • ubuntulinux-azure-6.14

    all

  • ubuntulinux-azure-6.17

    all

  • ubuntulinux-azure-6.2

    all

  • ubuntulinux-azure-6.5

    all

  • ubuntulinux-azure-6.8

    all

  • ubuntulinux-azure-edge

    all

  • ubuntulinux-azure-fde

    all | all | all | all | all

  • ubuntulinux-azure-fde-5.15

    all

  • ubuntulinux-azure-fde-5.19

    all

  • ubuntulinux-azure-fde-6.14

    all

  • ubuntulinux-azure-fde-6.17

    all

  • ubuntulinux-azure-fde-6.2

    all

  • ubuntulinux-azure-fde-6.8

    all

  • ubuntulinux-azure-fips

    all

  • ubuntulinux-azure-nvidia

    all

  • ubuntulinux-azure-nvidia-6.14

    all

  • ubuntulinux-bluefield

    all | all

  • ubuntulinux-fips

    all

  • ubuntulinux-gcp

    all | all | all | all | all

  • ubuntulinux-gcp-4.15

    all

  • ubuntulinux-gcp-5.11

    all

  • ubuntulinux-gcp-5.13

    all

Showing first 50 affected entries in server-rendered view.

References (3)