CVE-2025-38387

Published Jul 25, 2025

Last updated 10 months ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: RDMA/mlx5: Initialize obj_event->obj_sub_list before xa_insert The obj_event may be loaded immediately after inserted, then if the list_head is not initialized then we may get a poisonous pointer. This fixes the crash below: mlx5_core 0000:03:00.0: MLX5E: StrdRq(1) RqSz(8) StrdSz(2048) RxCqeCmprss(0 enhanced) mlx5_core.sf mlx5_core.sf.4: firmware version: 32.38.3056 mlx5_core 0000:03:00.0 en3f0pf0sf2002: renamed from eth0 mlx5_core.sf mlx5_core.sf.4: Rate limit: 127 rates are supported, range: 0Mbps to 195312Mbps IPv6: ADDRCONF(NETDEV_CHANGE): en3f0pf0sf2002: link becomes ready Unable to handle kernel NULL pointer dereference at virtual address 0000000000000060 Mem abort info: ESR = 0x96000006 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 Data abort info: ISV = 0, ISS = 0x00000006 CM = 0, WnR = 0 user pgtable: 4k pages, 48-bit VAs, pgdp=00000007760fb000 [0000000000000060] pgd=000000076f6d7003, p4d=000000076f6d7003, pud=0000000777841003, pmd=0000000000000000 Internal error: Oops: 96000006 [#1] SMP Modules linked in: ipmb_host(OE) act_mirred(E) cls_flower(E) sch_ingress(E) mptcp_diag(E) udp_diag(E) raw_diag(E) unix_diag(E) tcp_diag(E) inet_diag(E) binfmt_misc(E) bonding(OE) rdma_ucm(OE) rdma_cm(OE) iw_cm(OE) ib_ipoib(OE) ib_cm(OE) isofs(E) cdrom(E) mst_pciconf(OE) ib_umad(OE) mlx5_ib(OE) ipmb_dev_int(OE) mlx5_core(OE) kpatch_15237886(OEK) mlxdevm(OE) auxiliary(OE) ib_uverbs(OE) ib_core(OE) psample(E) mlxfw(OE) tls(E) sunrpc(E) vfat(E) fat(E) crct10dif_ce(E) ghash_ce(E) sha1_ce(E) sbsa_gwdt(E) virtio_console(E) ext4(E) mbcache(E) jbd2(E) xfs(E) libcrc32c(E) mmc_block(E) virtio_net(E) net_failover(E) failover(E) sha2_ce(E) sha256_arm64(E) nvme(OE) nvme_core(OE) gpio_mlxbf3(OE) mlx_compat(OE) mlxbf_pmc(OE) i2c_mlxbf(OE) sdhci_of_dwcmshc(OE) pinctrl_mlxbf3(OE) mlxbf_pka(OE) gpio_generic(E) i2c_core(E) mmc_core(E) mlxbf_gige(OE) vitesse(E) pwr_mlxbf(OE) mlxbf_tmfifo(OE) micrel(E) mlxbf_bootctl(OE) virtio_ring(E) virtio(E) ipmi_devintf(E) ipmi_msghandler(E) [last unloaded: mst_pci] CPU: 11 PID: 20913 Comm: rte-worker-11 Kdump: loaded Tainted: G OE K 5.10.134-13.1.an8.aarch64 #1 Hardware name: https://www.mellanox.com BlueField-3 SmartNIC Main Card/BlueField-3 SmartNIC Main Card, BIOS 4.2.2.12968 Oct 26 2023 pstate: a0400089 (NzCv daIf +PAN -UAO -TCO BTYPE=--) pc : dispatch_event_fd+0x68/0x300 [mlx5_ib] lr : devx_event_notifier+0xcc/0x228 [mlx5_ib] sp : ffff80001005bcf0 x29: ffff80001005bcf0 x28: 0000000000000001 x27: ffff244e0740a1d8 x26: ffff244e0740a1d0 x25: ffffda56beff5ae0 x24: ffffda56bf911618 x23: ffff244e0596a480 x22: ffff244e0596a480 x21: ffff244d8312ad90 x20: ffff244e0596a480 x19: fffffffffffffff0 x18: 0000000000000000 x17: 0000000000000000 x16: ffffda56be66d620 x15: 0000000000000000 x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 x11: 0000000000000040 x10: ffffda56bfcafb50 x9 : ffffda5655c25f2c x8 : 0000000000000010 x7 : 0000000000000000 x6 : ffff24545a2e24b8 x5 : 0000000000000003 x4 : ffff80001005bd28 x3 : 0000000000000000 x2 : 0000000000000000 x1 : ffff244e0596a480 x0 : ffff244d8312ad90 Call trace: dispatch_event_fd+0x68/0x300 [mlx5_ib] devx_event_notifier+0xcc/0x228 [mlx5_ib] atomic_notifier_call_chain+0x58/0x80 mlx5_eq_async_int+0x148/0x2b0 [mlx5_core] atomic_notifier_call_chain+0x58/0x80 irq_int_handler+0x20/0x30 [mlx5_core] __handle_irq_event_percpu+0x60/0x220 handle_irq_event_percpu+0x3c/0x90 handle_irq_event+0x58/0x158 handle_fasteoi_irq+0xfc/0x188 generic_handle_irq+0x34/0x48 ...
Source
416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD status
Analyzed
Products
linux_kernel, debian_linux

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-476

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