Linux Kernel up to 6.6.23/6.7.11/6.8.2 amdgpu deadlock

Summaryinfo

A vulnerability was found in Linux Kernel up to 6.6.23/6.7.11/6.8.2. It has been rated as critical. Impacted is an unknown function of the component amdgpu. The manipulation leads to deadlock. This vulnerability is traded as CVE-2024-35795. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.6.23/6.7.11/6.8.2 and classified as critical. This issue affects an unknown function of the component amdgpu. The manipulation with an unknown input leads to a deadlock vulnerability. Using CWE to declare the problem leads to CWE-833. The product contains multiple threads or executable segments that are waiting for each other to release a necessary lock, resulting in deadlock. Impacted is availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: drm/amdgpu: fix deadlock while reading mqd from debugfs An errant disk backup on my desktop got into debugfs and triggered the following deadlock scenario in the amdgpu debugfs files. The machine also hard-resets immediately after those lines are printed (although I wasn't able to reproduce that part when reading by hand): [ 1318.016074][ T1082] ====================================================== [ 1318.016607][ T1082] WARNING: possible circular locking dependency detected [ 1318.017107][ T1082] 6.8.0-rc7-00015-ge0c8221b72c0 #17 Not tainted [ 1318.017598][ T1082] ------------------------------------------------------ [ 1318.018096][ T1082] tar/1082 is trying to acquire lock: [ 1318.018585][ T1082] ffff98c44175d6a0 (&mm->mmap_lock){++++}-{3:3}, at: __might_fault+0x40/0x80 [ 1318.019084][ T1082] [ 1318.019084][ T1082] but task is already holding lock: [ 1318.020052][ T1082] ffff98c4c13f55f8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: amdgpu_debugfs_mqd_read+0x6a/0x250 [amdgpu] [ 1318.020607][ T1082] [ 1318.020607][ T1082] which lock already depends on the new lock. [ 1318.020607][ T1082] [ 1318.022081][ T1082] [ 1318.022081][ T1082] the existing dependency chain (in reverse order) is: [ 1318.023083][ T1082] [ 1318.023083][ T1082] -> #2 (reservation_ww_class_mutex){+.+.}-{3:3}: [ 1318.024114][ T1082] __ww_mutex_lock.constprop.0+0xe0/0x12f0 [ 1318.024639][ T1082] ww_mutex_lock+0x32/0x90 [ 1318.025161][ T1082] dma_resv_lockdep+0x18a/0x330 [ 1318.025683][ T1082] do_one_initcall+0x6a/0x350 [ 1318.026210][ T1082] kernel_init_freeable+0x1a3/0x310 [ 1318.026728][ T1082] kernel_init+0x15/0x1a0 [ 1318.027242][ T1082] ret_from_fork+0x2c/0x40 [ 1318.027759][ T1082] ret_from_fork_asm+0x11/0x20 [ 1318.028281][ T1082] [ 1318.028281][ T1082] -> #1 (reservation_ww_class_acquire){+.+.}-{0:0}: [ 1318.029297][ T1082] dma_resv_lockdep+0x16c/0x330 [ 1318.029790][ T1082] do_one_initcall+0x6a/0x350 [ 1318.030263][ T1082] kernel_init_freeable+0x1a3/0x310 [ 1318.030722][ T1082] kernel_init+0x15/0x1a0 [ 1318.031168][ T1082] ret_from_fork+0x2c/0x40 [ 1318.031598][ T1082] ret_from_fork_asm+0x11/0x20 [ 1318.032011][ T1082] [ 1318.032011][ T1082] -> #0 (&mm->mmap_lock){++++}-{3:3}: [ 1318.032778][ T1082] __lock_acquire+0x14bf/0x2680 [ 1318.033141][ T1082] lock_acquire+0xcd/0x2c0 [ 1318.033487][ T1082] __might_fault+0x58/0x80 [ 1318.033814][ T1082] amdgpu_debugfs_mqd_read+0x103/0x250 [amdgpu] [ 1318.034181][ T1082] full_proxy_read+0x55/0x80 [ 1318.034487][ T1082] vfs_read+0xa7/0x360 [ 1318.034788][ T1082] ksys_read+0x70/0xf0 [ 1318.035085][ T1082] do_syscall_64+0x94/0x180 [ 1318.035375][ T1082] entry_SYSCALL_64_after_hwframe+0x46/0x4e [ 1318.035664][ T1082] [ 1318.035664][ T1082] other info that might help us debug this: [ 1318.035664][ T1082] [ 1318.036487][ T1082] Chain exists of: [ 1318.036487][ T1082] &mm->mmap_lock --> reservation_ww_class_acquire --> reservation_ww_class_mutex [ 1318.036487][ T1082] [ 1318.037310][ T1082] Possible unsafe locking scenario: [ 1318.037310][ T1082] [ 1318.037838][ T1082] CPU0 CPU1 [ 1318.038101][ T1082] ---- ---- [ 1318.038350][ T1082] lock(reservation_ww_class_mutex); [ 1318.038590][ T1082] lock(reservation_ww_class_acquire); [ 1318.038839][ T1082] lock(reservation_ww_class_mutex); [ 1318.039083][ T1082] rlock(&mm->mmap_lock); [ 1318.039328][ T1082] [ 1318.039328][ T1082] *** DEADLOCK *** [ 1318.039328][ T1082] [ 1318.040029][ T1082] 1 lock held by tar/1082: [ 1318.040259][ T1082] #0: ffff98c4c13f55f8 (reservation_ww_class_mutex){+.+.}-{3:3}, at: amdgpu_debugfs_mqd_read+0x6a/0x250 [amdgpu] [ 1318.040560][ T1082] [ 1318.040560][ T1082] stack backtrace: [ ---truncated---

The advisory is shared at git.kernel.org. The identification of this vulnerability is CVE-2024-35795. The exploitation is known to be difficult. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 210815 (RHEL 9 : kernel (RHSA-2024:9315)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 6.6.24, 6.7.12 or 6.8.3 eliminates this vulnerability. Applying the patch 197f6d6987c5/8b03556da6e5/4687e3c6ee87/8678b1060ae2 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (210815) and CERT Bund (WID-SEC-2024-1188). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• Google Container-Optimized OS
• Debian Linux
• Amazon Linux 2
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• IBM InfoSphere Guardium
• Oracle Linux
• Oracle VM
• NetApp FAS
• EMC Avamar
• IBM SAN Volume Controller
• Dell NetWorker
• IBM FlashSystem
• IBM Security Guardium
• RESF Rocky Linux
• Broadcom Brocade SANnav
• Open Source Linux Kernel
• IBM Business Automation Workflow
• IBM Spectrum Protect Plus
• IBM QRadar SIEM
• Dell Avamar
• Juniper Junos Space
• IBM DB2
• IBM Storage Scale System
• SolarWinds Security Event Manager

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.6.0
• 6.6.1
• 6.6.2
• 6.6.3
• 6.6.4
• 6.6.5
• 6.6.6
• 6.6.7
• 6.6.8
• 6.6.9
• 6.6.10
• 6.6.11
• 6.6.12
• 6.6.13
• 6.6.14
• 6.6.15
• 6.6.16
• 6.6.17
• 6.6.18
• 6.6.19
• 6.6.20
• 6.6.21
• 6.6.22
• 6.6.23
• 6.7.0
• 6.7.1
• 6.7.2
• 6.7.3
• 6.7.4
• 6.7.5
• 6.7.6
• 6.7.7
• 6.7.8
• 6.7.9
• 6.7.10
• 6.7.11
• 6.8.0
• 6.8.1
• 6.8.2

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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