CVE-2025-39739

Published Sep 11, 2025

Last updated 4 days ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: iommu/arm-smmu-qcom: Add SM6115 MDSS compatible Add the SM6115 MDSS compatible to clients compatible list, as it also needs that workaround. Without this workaround, for example, QRB4210 RB2 which is based on SM4250/SM6115 generates a lot of smmu unhandled context faults during boot: arm_smmu_context_fault: 116854 callbacks suppressed arm-smmu c600000.iommu: Unhandled context fault: fsr=0x402, iova=0x5c0ec600, fsynr=0x320021, cbfrsynra=0x420, cb=5 arm-smmu c600000.iommu: FSR = 00000402 [Format=2 TF], SID=0x420 arm-smmu c600000.iommu: FSYNR0 = 00320021 [S1CBNDX=50 PNU PLVL=1] arm-smmu c600000.iommu: Unhandled context fault: fsr=0x402, iova=0x5c0d7800, fsynr=0x320021, cbfrsynra=0x420, cb=5 arm-smmu c600000.iommu: FSR = 00000402 [Format=2 TF], SID=0x420 and also failed initialisation of lontium lt9611uxc, gpu and dpu is observed: (binding MDSS components triggered by lt9611uxc have failed) ------------[ cut here ]------------ !aspace WARNING: CPU: 6 PID: 324 at drivers/gpu/drm/msm/msm_gem_vma.c:130 msm_gem_vma_init+0x150/0x18c [msm] Modules linked in: ... (long list of modules) CPU: 6 UID: 0 PID: 324 Comm: (udev-worker) Not tainted 6.15.0-03037-gaacc73ceeb8b #4 PREEMPT Hardware name: Qualcomm Technologies, Inc. QRB4210 RB2 (DT) pstate: 80000005 (Nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : msm_gem_vma_init+0x150/0x18c [msm] lr : msm_gem_vma_init+0x150/0x18c [msm] sp : ffff80008144b280 ... Call trace: msm_gem_vma_init+0x150/0x18c [msm] (P) get_vma_locked+0xc0/0x194 [msm] msm_gem_get_and_pin_iova_range+0x4c/0xdc [msm] msm_gem_kernel_new+0x48/0x160 [msm] msm_gpu_init+0x34c/0x53c [msm] adreno_gpu_init+0x1b0/0x2d8 [msm] a6xx_gpu_init+0x1e8/0x9e0 [msm] adreno_bind+0x2b8/0x348 [msm] component_bind_all+0x100/0x230 msm_drm_bind+0x13c/0x3d0 [msm] try_to_bring_up_aggregate_device+0x164/0x1d0 __component_add+0xa4/0x174 component_add+0x14/0x20 dsi_dev_attach+0x20/0x34 [msm] dsi_host_attach+0x58/0x98 [msm] devm_mipi_dsi_attach+0x34/0x90 lt9611uxc_attach_dsi.isra.0+0x94/0x124 [lontium_lt9611uxc] lt9611uxc_probe+0x540/0x5fc [lontium_lt9611uxc] i2c_device_probe+0x148/0x2a8 really_probe+0xbc/0x2c0 __driver_probe_device+0x78/0x120 driver_probe_device+0x3c/0x154 __driver_attach+0x90/0x1a0 bus_for_each_dev+0x68/0xb8 driver_attach+0x24/0x30 bus_add_driver+0xe4/0x208 driver_register+0x68/0x124 i2c_register_driver+0x48/0xcc lt9611uxc_driver_init+0x20/0x1000 [lontium_lt9611uxc] do_one_initcall+0x60/0x1d4 do_init_module+0x54/0x1fc load_module+0x1748/0x1c8c init_module_from_file+0x74/0xa0 __arm64_sys_finit_module+0x130/0x2f8 invoke_syscall+0x48/0x104 el0_svc_common.constprop.0+0xc0/0xe0 do_el0_svc+0x1c/0x28 el0_svc+0x2c/0x80 el0t_64_sync_handler+0x10c/0x138 el0t_64_sync+0x198/0x19c ---[ end trace 0000000000000000 ]--- msm_dpu 5e01000.display-controller: [drm:msm_gpu_init [msm]] *ERROR* could not allocate memptrs: -22 msm_dpu 5e01000.display-controller: failed to load adreno gpu platform a400000.remoteproc:glink-edge:apr:service@7:dais: Adding to iommu group 19 msm_dpu 5e01000.display-controller: failed to bind 5900000.gpu (ops a3xx_ops [msm]): -22 msm_dpu 5e01000.display-controller: adev bind failed: -22 lt9611uxc 0-002b: failed to attach dsi to host lt9611uxc 0-002b: probe with driver lt9611uxc failed with error -22
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
NVD-CWE-noinfo

Social media

Hype score
Not currently trending

Configurations

  1. In the Linux kernel, the following vulnerability has been resolved: cgroup: Avoid iteration of dying tasks with zero refcount The commit 260fbcb92bbea ("cgroup: Move dying_tasks cleanup from cgroup_task_release() to cgroup_task_free()") extended the lifetime of tasks on the dying_tasks list. The iterators have provision to go through dying_tasks because of dying threadgroup leaders or explicit CSS_TASK_ITER_WITH_DEAD, however, it was expected that such tasks can obtain a new reference (that is possible before cgroup_task_release()/put_task_struct_rcu_user()). The tasks after cgroup_task_release() and before cgroup_task_free() are subject to race when they may or may not have ->usage count > 0. The race window is between css_task_iter_next() invocations when css_set_lock is released and we may arrive at a new ->task_pos. The iterator should not attempt to resurrect tasks whose ->usage count dropped to zero. (When that happens, __put_task_struct_rcu_cb() is already imminent and the returned task_struct would could be used after free.) As for the fix, we cannot simply check the signal->live count of a task on the dying list because that won't distinguish regular zombies waiting to be reaped from RCU remnant tasks that are going to be free'd. Therefore add an extra check to rule out ->usage==0 tasks from any iteration. The repeat: loop in css_task_iter_advance() doesn't consider ->usage count, so add a new loop to css_task_iter_next() to skip de-used tasks on the dying_list. Rough illustration of the possible race R (reader of cgroup.procs) T (thread) L (group leader) --------------------------------- -------------------------------- -------------------------------- L exits, signal->live > 0 cgroup_task_dead(L) css_set_skip_task_iters() // skips only cset->tasks list_add_tail(&L->cg_list, &cset->dying_tasks) css_task_iter_next() take css_set_lock css_task_iter_advance() leader && signal->live != 0 => it->task_pos = &L->cg_list release css_set_lock T exits --signal->live == 0 cgroup_task_dead(T) // css_set_lock release_task(T) cgroup_task_release(T) release_task(L) // zap_leader cgroup_task_release(L) put_task_struct_rcu_user(L) ...RCU... put_task_struct(L) L->usage = 0 /* L still on dying_tasks */ ...RCU... __put_task_struct(L) css_task_iter_next() // another iteration take css_set_lock it->task_pos = &L->cg_list get_task_struct(L) => addition on 0 drop css_set_lock cgroup_task_free(L) css_set_skip_task_iters() // dying skip comes too late free_task(L) cgroup_procs_show() task_pid_vnr(L)•CVE-2026-98163