CVE-2022-50004

Published Jun 18, 2025

Last updated 7 months ago

Overview

Description
In the Linux kernel, the following vulnerability has been resolved: xfrm: policy: fix metadata dst->dev xmit null pointer dereference When we try to transmit an skb with metadata_dst attached (i.e. dst->dev == NULL) through xfrm interface we can hit a null pointer dereference[1] in xfrmi_xmit2() -> xfrm_lookup_with_ifid() due to the check for a loopback skb device when there's no policy which dereferences dst->dev unconditionally. Not having dst->dev can be interepreted as it not being a loopback device, so just add a check for a null dst_orig->dev. With this fix xfrm interface's Tx error counters go up as usual. [1] net-next calltrace captured via netconsole: BUG: kernel NULL pointer dereference, address: 00000000000000c0 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 0 P4D 0 Oops: 0000 [#1] PREEMPT SMP CPU: 1 PID: 7231 Comm: ping Kdump: loaded Not tainted 5.19.0+ #24 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.0-1.fc36 04/01/2014 RIP: 0010:xfrm_lookup_with_ifid+0x5eb/0xa60 Code: 8d 74 24 38 e8 26 a4 37 00 48 89 c1 e9 12 fc ff ff 49 63 ed 41 83 fd be 0f 85 be 01 00 00 41 be ff ff ff ff 45 31 ed 48 8b 03 <f6> 80 c0 00 00 00 08 75 0f 41 80 bc 24 19 0d 00 00 01 0f 84 1e 02 RSP: 0018:ffffb0db82c679f0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffd0db7fcad430 RCX: ffffb0db82c67a10 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffb0db82c67a80 RBP: ffffb0db82c67a80 R08: ffffb0db82c67a14 R09: 0000000000000000 R10: 0000000000000000 R11: ffff8fa449667dc8 R12: ffffffff966db880 R13: 0000000000000000 R14: 00000000ffffffff R15: 0000000000000000 FS: 00007ff35c83f000(0000) GS:ffff8fa478480000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000000000c0 CR3: 000000001ebb7000 CR4: 0000000000350ee0 Call Trace: <TASK> xfrmi_xmit+0xde/0x460 ? tcf_bpf_act+0x13d/0x2a0 dev_hard_start_xmit+0x72/0x1e0 __dev_queue_xmit+0x251/0xd30 ip_finish_output2+0x140/0x550 ip_push_pending_frames+0x56/0x80 raw_sendmsg+0x663/0x10a0 ? try_charge_memcg+0x3fd/0x7a0 ? __mod_memcg_lruvec_state+0x93/0x110 ? sock_sendmsg+0x30/0x40 sock_sendmsg+0x30/0x40 __sys_sendto+0xeb/0x130 ? handle_mm_fault+0xae/0x280 ? do_user_addr_fault+0x1e7/0x680 ? kvm_read_and_reset_apf_flags+0x3b/0x50 __x64_sys_sendto+0x20/0x30 do_syscall_64+0x34/0x80 entry_SYSCALL_64_after_hwframe+0x46/0xb0 RIP: 0033:0x7ff35cac1366 Code: eb 0b 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b8 0f 1f 00 41 89 ca 64 8b 04 25 18 00 00 00 85 c0 75 11 b8 2c 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 72 c3 90 55 48 83 ec 30 44 89 4c 24 2c 4c 89 RSP: 002b:00007fff738e4028 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007fff738e57b0 RCX: 00007ff35cac1366 RDX: 0000000000000040 RSI: 0000557164e4b450 RDI: 0000000000000003 RBP: 0000557164e4b450 R08: 00007fff738e7a2c R09: 0000000000000010 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000040 R13: 00007fff738e5770 R14: 00007fff738e4030 R15: 0000001d00000001 </TASK> Modules linked in: netconsole veth br_netfilter bridge bonding virtio_net [last unloaded: netconsole] CR2: 00000000000000c0
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-476

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