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---
References
Configurations
Configuration 1 (hide)
|
History
10 Jan 2025, 18:10
Type | Values Removed | Values Added |
---|---|---|
CWE | CWE-667 | |
First Time |
Linux linux Kernel
Linux |
|
References | () https://git.kernel.org/stable/c/197f6d6987c55860f6eea1c93e4f800c59078874 - Patch | |
References | () https://git.kernel.org/stable/c/4687e3c6ee877ee25e57b984eca00be53b9a8db5 - Patch | |
References | () https://git.kernel.org/stable/c/8678b1060ae2b75feb60b87e5b75e17374e3c1c5 - Patch | |
References | () https://git.kernel.org/stable/c/8b03556da6e576c62664b6cd01809e4a09d53b5b - Patch | |
CVSS |
v2 : v3 : |
v2 : unknown
v3 : 5.5 |
CPE | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* cpe:2.3:o:linux:linux_kernel:6.9:rc1:*:*:*:*:*:* |
Information
Published : 2024-05-17 14:15
Updated : 2025-01-10 18:10
NVD link : CVE-2024-35795
Mitre link : CVE-2024-35795
CVE.ORG link : CVE-2024-35795
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-667
Improper Locking