Alex Deucher 77f7325301 drm/amdgpu: fix a job->pasid access race in gpu recovery
Avoid a possible UAF in GPU recovery due to a race between
the sched timeout callback and the tdr work queue.

The gpu recovery function calls drm_sched_stop() and
later drm_sched_start().  drm_sched_start() restarts
the tdr queue which will eventually free the job.  If
the tdr queue frees the job before time out callback
completes, the job will be freed and we'll get a UAF
when accessing the pasid.  Cache it early to avoid the
UAF.

Example KASAN trace:
[  493.058141] BUG: KASAN: slab-use-after-free in amdgpu_device_gpu_recover+0x968/0x990 [amdgpu]
[  493.067530] Read of size 4 at addr ffff88b0ce3f794c by task kworker/u128:1/323
[  493.074892]
[  493.076485] CPU: 9 UID: 0 PID: 323 Comm: kworker/u128:1 Tainted: G            E       6.16.0-1289896.2.zuul.bf4f11df81c1410bbe901c4373305a31 #1 PREEMPT(voluntary)
[  493.076493] Tainted: [E]=UNSIGNED_MODULE
[  493.076495] Hardware name: TYAN B8021G88V2HR-2T/S8021GM2NR-2T, BIOS V1.03.B10 04/01/2019
[  493.076500] Workqueue: amdgpu-reset-dev drm_sched_job_timedout [gpu_sched]
[  493.076512] Call Trace:
[  493.076515]  <TASK>
[  493.076518]  dump_stack_lvl+0x64/0x80
[  493.076529]  print_report+0xce/0x630
[  493.076536]  ? _raw_spin_lock_irqsave+0x86/0xd0
[  493.076541]  ? __pfx__raw_spin_lock_irqsave+0x10/0x10
[  493.076545]  ? amdgpu_device_gpu_recover+0x968/0x990 [amdgpu]
[  493.077253]  kasan_report+0xb8/0xf0
[  493.077258]  ? amdgpu_device_gpu_recover+0x968/0x990 [amdgpu]
[  493.077965]  amdgpu_device_gpu_recover+0x968/0x990 [amdgpu]
[  493.078672]  ? __pfx_amdgpu_device_gpu_recover+0x10/0x10 [amdgpu]
[  493.079378]  ? amdgpu_coredump+0x1fd/0x4c0 [amdgpu]
[  493.080111]  amdgpu_job_timedout+0x642/0x1400 [amdgpu]
[  493.080903]  ? pick_task_fair+0x24e/0x330
[  493.080910]  ? __pfx_amdgpu_job_timedout+0x10/0x10 [amdgpu]
[  493.081702]  ? _raw_spin_lock+0x75/0xc0
[  493.081708]  ? __pfx__raw_spin_lock+0x10/0x10
[  493.081712]  drm_sched_job_timedout+0x1b0/0x4b0 [gpu_sched]
[  493.081721]  ? __pfx__raw_spin_lock_irq+0x10/0x10
[  493.081725]  process_one_work+0x679/0xff0
[  493.081732]  worker_thread+0x6ce/0xfd0
[  493.081736]  ? __pfx_worker_thread+0x10/0x10
[  493.081739]  kthread+0x376/0x730
[  493.081744]  ? __pfx_kthread+0x10/0x10
[  493.081748]  ? __pfx__raw_spin_lock_irq+0x10/0x10
[  493.081751]  ? __pfx_kthread+0x10/0x10
[  493.081755]  ret_from_fork+0x247/0x330
[  493.081761]  ? __pfx_kthread+0x10/0x10
[  493.081764]  ret_from_fork_asm+0x1a/0x30
[  493.081771]  </TASK>

Fixes: a72002cb18 ("drm/amdgpu: Make use of drm_wedge_task_info")
Link: https://github.com/HansKristian-Work/vkd3d-proton/pull/2670
Cc: SRINIVASAN.SHANMUGAM@amd.com
Cc: vitaly.prosyak@amd.com
Cc: christian.koenig@amd.com
Suggested-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Srinivasan Shanmugam <srinivasan.shanmugam@amd.com>
Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
(cherry picked from commit 20880a3fd5)
2025-12-16 14:16:08 -05:00
2022-09-28 09:02:20 +02:00
2025-02-19 14:53:27 -07:00
2025-12-14 16:05:07 +12:00

Linux kernel
============

The Linux kernel is the core of any Linux operating system. It manages hardware,
system resources, and provides the fundamental services for all other software.

Quick Start
-----------

* Report a bug: See Documentation/admin-guide/reporting-issues.rst
* Get the latest kernel: https://kernel.org
* Build the kernel: See Documentation/admin-guide/quickly-build-trimmed-linux.rst
* Join the community: https://lore.kernel.org/

Essential Documentation
-----------------------

All users should be familiar with:

* Building requirements: Documentation/process/changes.rst
* Code of Conduct: Documentation/process/code-of-conduct.rst
* License: See COPYING

Documentation can be built with make htmldocs or viewed online at:
https://www.kernel.org/doc/html/latest/


Who Are You?
============

Find your role below:

* New Kernel Developer - Getting started with kernel development
* Academic Researcher - Studying kernel internals and architecture
* Security Expert - Hardening and vulnerability analysis
* Backport/Maintenance Engineer - Maintaining stable kernels
* System Administrator - Configuring and troubleshooting
* Maintainer - Leading subsystems and reviewing patches
* Hardware Vendor - Writing drivers for new hardware
* Distribution Maintainer - Packaging kernels for distros


For Specific Users
==================

New Kernel Developer
--------------------

Welcome! Start your kernel development journey here:

* Getting Started: Documentation/process/development-process.rst
* Your First Patch: Documentation/process/submitting-patches.rst
* Coding Style: Documentation/process/coding-style.rst
* Build System: Documentation/kbuild/index.rst
* Development Tools: Documentation/dev-tools/index.rst
* Kernel Hacking Guide: Documentation/kernel-hacking/hacking.rst
* Core APIs: Documentation/core-api/index.rst

Academic Researcher
-------------------

Explore the kernel's architecture and internals:

* Researcher Guidelines: Documentation/process/researcher-guidelines.rst
* Memory Management: Documentation/mm/index.rst
* Scheduler: Documentation/scheduler/index.rst
* Networking Stack: Documentation/networking/index.rst
* Filesystems: Documentation/filesystems/index.rst
* RCU (Read-Copy Update): Documentation/RCU/index.rst
* Locking Primitives: Documentation/locking/index.rst
* Power Management: Documentation/power/index.rst

Security Expert
---------------

Security documentation and hardening guides:

* Security Documentation: Documentation/security/index.rst
* LSM Development: Documentation/security/lsm-development.rst
* Self Protection: Documentation/security/self-protection.rst
* Reporting Vulnerabilities: Documentation/process/security-bugs.rst
* CVE Procedures: Documentation/process/cve.rst
* Embargoed Hardware Issues: Documentation/process/embargoed-hardware-issues.rst
* Security Features: Documentation/userspace-api/seccomp_filter.rst

Backport/Maintenance Engineer
-----------------------------

Maintain and stabilize kernel versions:

* Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst
* Backporting Guide: Documentation/process/backporting.rst
* Applying Patches: Documentation/process/applying-patches.rst
* Subsystem Profile: Documentation/maintainer/maintainer-entry-profile.rst
* Git for Maintainers: Documentation/maintainer/configure-git.rst

System Administrator
--------------------

Configure, tune, and troubleshoot Linux systems:

* Admin Guide: Documentation/admin-guide/index.rst
* Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst
* Sysctl Tuning: Documentation/admin-guide/sysctl/index.rst
* Tracing/Debugging: Documentation/trace/index.rst
* Performance Security: Documentation/admin-guide/perf-security.rst
* Hardware Monitoring: Documentation/hwmon/index.rst

Maintainer
----------

Lead kernel subsystems and manage contributions:

* Maintainer Handbook: Documentation/maintainer/index.rst
* Pull Requests: Documentation/maintainer/pull-requests.rst
* Managing Patches: Documentation/maintainer/modifying-patches.rst
* Rebasing and Merging: Documentation/maintainer/rebasing-and-merging.rst
* Development Process: Documentation/process/maintainer-handbooks.rst
* Maintainer Entry Profile: Documentation/maintainer/maintainer-entry-profile.rst
* Git Configuration: Documentation/maintainer/configure-git.rst

Hardware Vendor
---------------

Write drivers and support new hardware:

* Driver API Guide: Documentation/driver-api/index.rst
* Driver Model: Documentation/driver-api/driver-model/driver.rst
* Device Drivers: Documentation/driver-api/infrastructure.rst
* Bus Types: Documentation/driver-api/driver-model/bus.rst
* Device Tree Bindings: Documentation/devicetree/bindings/
* Power Management: Documentation/driver-api/pm/index.rst
* DMA API: Documentation/core-api/dma-api.rst

Distribution Maintainer
-----------------------

Package and distribute the kernel:

* Stable Kernel Rules: Documentation/process/stable-kernel-rules.rst
* ABI Documentation: Documentation/ABI/README
* Kernel Configuration: Documentation/kbuild/kconfig.rst
* Module Signing: Documentation/admin-guide/module-signing.rst
* Kernel Parameters: Documentation/admin-guide/kernel-parameters.rst
* Tainted Kernels: Documentation/admin-guide/tainted-kernels.rst



Communication and Support
=========================

* Mailing Lists: https://lore.kernel.org/
* IRC: #kernelnewbies on irc.oftc.net
* Bugzilla: https://bugzilla.kernel.org/
* MAINTAINERS file: Lists subsystem maintainers and mailing lists
* Email Clients: Documentation/process/email-clients.rst
Description
No description provided
Readme 3.7 GiB
Languages
C 97.1%
Assembly 1%
Shell 0.6%
Rust 0.4%
Python 0.4%
Other 0.3%