CVE-2023-53029

Published Mar 27, 2025

Last updated 7 months ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: octeontx2-pf: Fix the use of GFP_KERNEL in atomic context on rt The commit 4af1b64f80fb ("octeontx2-pf: Fix lmtst ID used in aura free") uses the get/put_cpu() to protect the usage of percpu pointer in ->aura_freeptr() callback, but it also unnecessarily disable the preemption for the blockable memory allocation. The commit 87b93b678e95 ("octeontx2-pf: Avoid use of GFP_KERNEL in atomic context") tried to fix these sleep inside atomic warnings. But it only fix the one for the non-rt kernel. For the rt kernel, we still get the similar warnings like below. BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:46 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1, name: swapper/0 preempt_count: 1, expected: 0 RCU nest depth: 0, expected: 0 3 locks held by swapper/0/1: #0: ffff800009fc5fe8 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock+0x24/0x30 #1: ffff000100c276c0 (&mbox->lock){+.+.}-{3:3}, at: otx2_init_hw_resources+0x8c/0x3a4 #2: ffffffbfef6537e0 (&cpu_rcache->lock){+.+.}-{2:2}, at: alloc_iova_fast+0x1ac/0x2ac Preemption disabled at: [<ffff800008b1908c>] otx2_rq_aura_pool_init+0x14c/0x284 CPU: 20 PID: 1 Comm: swapper/0 Tainted: G W 6.2.0-rc3-rt1-yocto-preempt-rt #1 Hardware name: Marvell OcteonTX CN96XX board (DT) Call trace: dump_backtrace.part.0+0xe8/0xf4 show_stack+0x20/0x30 dump_stack_lvl+0x9c/0xd8 dump_stack+0x18/0x34 __might_resched+0x188/0x224 rt_spin_lock+0x64/0x110 alloc_iova_fast+0x1ac/0x2ac iommu_dma_alloc_iova+0xd4/0x110 __iommu_dma_map+0x80/0x144 iommu_dma_map_page+0xe8/0x260 dma_map_page_attrs+0xb4/0xc0 __otx2_alloc_rbuf+0x90/0x150 otx2_rq_aura_pool_init+0x1c8/0x284 otx2_init_hw_resources+0xe4/0x3a4 otx2_open+0xf0/0x610 __dev_open+0x104/0x224 __dev_change_flags+0x1e4/0x274 dev_change_flags+0x2c/0x7c ic_open_devs+0x124/0x2f8 ip_auto_config+0x180/0x42c do_one_initcall+0x90/0x4dc do_basic_setup+0x10c/0x14c kernel_init_freeable+0x10c/0x13c kernel_init+0x2c/0x140 ret_from_fork+0x10/0x20 Of course, we can shuffle the get/put_cpu() to only wrap the invocation of ->aura_freeptr() as what commit 87b93b678e95 does. But there are only two ->aura_freeptr() callbacks, otx2_aura_freeptr() and cn10k_aura_freeptr(). There is no usage of perpcu variable in the otx2_aura_freeptr() at all, so the get/put_cpu() seems redundant to it. We can move the get/put_cpu() into the corresponding callback which really has the percpu variable usage and avoid the sprinkling of get/put_cpu() in several places.
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
Products
linux_kernel

Risk scores

CVSS 3.1

Type
Primary
Base score
5.5
Impact score
3.6
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Severity
MEDIUM

Weaknesses

nvd@nist.gov
CWE-667

Social media

Hype score
Not currently trending

Configurations

  1. In the Linux kernel, the following vulnerability has been resolved: coresight: tmc-etr: Fix race condition between sysfs and perf mode When trying to run perf and sysfs mode simultaneously, the WARN_ON() in tmc_etr_enable_hw() is triggered sometimes: WARNING: CPU: 42 PID: 3911571 at drivers/hwtracing/coresight/coresight-tmc-etr.c:1060 tmc_etr_enable_hw+0xc0/0xd8 [coresight_tmc] [..snip..] Call trace: tmc_etr_enable_hw+0xc0/0xd8 [coresight_tmc] (P) tmc_enable_etr_sink+0x11c/0x250 [coresight_tmc] (L) tmc_enable_etr_sink+0x11c/0x250 [coresight_tmc] coresight_enable_path+0x1c8/0x218 [coresight] coresight_enable_sysfs+0xa4/0x228 [coresight] enable_source_store+0x58/0xa8 [coresight] dev_attr_store+0x20/0x40 sysfs_kf_write+0x4c/0x68 kernfs_fop_write_iter+0x120/0x1b8 vfs_write+0x2c8/0x388 ksys_write+0x74/0x108 __arm64_sys_write+0x24/0x38 el0_svc_common.constprop.0+0x64/0x148 do_el0_svc+0x24/0x38 el0_svc+0x3c/0x130 el0t_64_sync_handler+0xc8/0xd0 el0t_64_sync+0x1ac/0x1b0 ---[ end trace 0000000000000000 ]--- Since the enablement of sysfs mode is separeted into two critical regions, one for sysfs buffer allocation and another for hardware enablement, it's possible to race with the perf mode. Fix this by double check whether the perf mode's been used before enabling the hardware in sysfs mode. mode: [sysfs mode] [perf mode] tmc_etr_get_sysfs_buffer() spin_lock(&drvdata->spinlock) [sysfs buffer allocation] spin_unlock(&drvdata->spinlock) spin_lock(&drvdata->spinlock) tmc_etr_enable_hw() drvdata->etr_buf = etr_perf->etr_buf spin_unlock(&drvdata->spinlock) spin_lock(&drvdata->spinlock) tmc_etr_enable_hw() WARN_ON(drvdata->etr_buf) // WARN sicne etr_buf initialized at the perf side spin_unlock(&drvdata->spinlock) With this fix, we retain the check for CS_MODE_PERF in get_etr_sysfs_buf. This ensures we verify whether the perf mode's already running before we actually allocate the buffer. Then we can save the time of allocating/freeing the sysfs buffer if race with the perf mode.CVE-2026-46272