CVE-2026-93809

Received Received - Intake

Kernel Page Fault in AMDGPU Driver Due to RCU Callback Handling

Publication date: 2026-09-24

Last updated on: 2026-09-25

Assigner: kernel.org

Description

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: flush pending RCU callbacks on module unload Call rcu_barrier() in module exit to wait for outstanding call_rcu() callbacks before freeing module text, preventing late callback execution in freed memory. BUG: unable to handle page fault for address: ffffffffc1d59c40 PGD 6a12067 P4D 6a12067 PUD 6a14067 PMD 13698b067 PTE 0 Oops: 0010 [#1] SMP NOPTI RIP: 0010:0xffffffffc1d59c40 Code: Unable to access opcode bytes at RIP 0xffffffffc1d59c16. RSP: 0018:ffffc900198c0f28 EFLAGS: 00010286 RAX: ffffffffc1d59c40 RBX: ffff897c7d6b61c0 RCX: ffff88826aff4590 RDX: ffff8884d8b35490 RSI: ffffc900198c0f30 RDI: ffff88812af67290 RBP: 000000000000000a (DONE segment entries) R08: 0000000000000000 R09: 0000000000000100 R10: 0000000000000000 R11: ffffffff82a06100 R12: ffff88811a4e3700 R13: 0000000000000000 R14: ffff897c7d6b6270 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff897c7d680000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffc1d59c16 CR3: 00000104a980a001 CR4: 0000000002770ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: <IRQ> ? rcu_do_batch+0x163/0x450 ? rcu_core+0x177/0x1c0 ? __do_softirq+0xc1/0x280 ? asm_call_irq_on_stack+0xf/0x20 </IRQ> ? do_softirq_own_stack+0x37/0x50 ? irq_exit_rcu+0xc4/0x100 ? sysvec_apic_timer_interrupt+0x36/0x80 ? asm_sysvec_apic_timer_interrupt+0x12/0x20 ? cpuidle_enter_state+0xd4/0x360 ? cpuidle_enter+0x29/0x40 ? cpuidle_idle_call+0x108/0x1a0 ? do_idle+0x77/0xf0 ? cpu_startup_entry+0x19/0x20 ? secondary_startup_64_no_verify+0xbf/0xcb (cherry picked from commit feaa5039f6c12acc9aa934c2d45dcd251a12c69f)

CVSS Scores

EPSS Scores

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Meta Information

Published

2026-09-24

Last Modified

2026-09-25

Generated

2026-10-15

AI Q&A

2026-09-24

EPSS Evaluated

2026-10-13

NVD

CVE-2026-93809

EUVD

EUVD-2026-86196

Affected Vendors & Products

Vendor	Product	Version / Range
linux	linux_kernel	*

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-UNKNOWN

Attack-Flow Graph

Executive Summary

This vulnerability in the Linux kernel involves a page fault error during module unloading in the AMDGPU driver. The issue occurs because pending RCU callbacks are not properly flushed before the module's memory is freed, leading to late callback execution in freed memory. This can cause system instability or crashes.

Detection Guidance

This vulnerability is specific to the Linux kernel's AMDGPU driver and may cause kernel oops or page faults during module unload. Detection requires checking kernel logs for related errors or crashes. Use commands like 'dmesg | grep -i oops' or 'journalctl -k | grep -i page fault' to identify issues.

Impact Analysis

This vulnerability may cause system crashes or instability when unloading the AMDGPU kernel module. Users could experience kernel oops, freezes, or unexpected reboots, potentially leading to data loss or service disruption.

Compliance Impact

This vulnerability does not directly affect compliance with GDPR, HIPAA, or similar standards as it is a Linux kernel memory management issue that could lead to system crashes or instability. Compliance impacts would only occur if the vulnerability causes data loss or unauthorized access, which is not specified in the provided context.

Mitigation Strategies

Apply the latest kernel update that includes the fix for this AMDGPU driver issue. Reboot the system to ensure the patched kernel is active. Monitor kernel logs for any remaining errors after update.

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