{
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"cveMetadata": {
"cveId": "CVE-2022-50373",
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"state": "PUBLISHED",
"assignerShortName": "Linux",
"dateReserved": "2025-09-17T14:53:06.995Z",
"datePublished": "2025-09-17T14:56:28.282Z",
"dateUpdated": "2026-08-05T08:58:28.255Z"
},
"containers": {
"cna": {
"providerMetadata": {
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux",
"dateUpdated": "2026-08-05T08:58:28.255Z"
},
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nfs: dlm: fix race in lowcomms\n\nThis patch fixes a race between queue_work() in\n_dlm_lowcomms_commit_msg() and srcu_read_unlock(). The queue_work() can\ntake the final reference of a dlm_msg and so msg->idx can contain\ngarbage which is signaled by the following warning:\n\n[ 676.237050] ------------[ cut here ]------------\n[ 676.237052] WARNING: CPU: 0 PID: 1060 at include/linux/srcu.h:189 dlm_lowcomms_commit_msg+0x41/0x50\n[ 676.238945] Modules linked in: dlm_locktorture torture rpcsec_gss_krb5 intel_rapl_msr intel_rapl_common iTCO_wdt iTCO_vendor_support qxl kvm_intel drm_ttm_helper vmw_vsock_virtio_transport kvm vmw_vsock_virtio_transport_common ttm irqbypass crc32_pclmul joydev crc32c_intel serio_raw drm_kms_helper vsock virtio_scsi virtio_console virtio_balloon snd_pcm drm syscopyarea sysfillrect sysimgblt snd_timer fb_sys_fops i2c_i801 lpc_ich snd i2c_smbus soundcore pcspkr\n[ 676.244227] CPU: 0 PID: 1060 Comm: lock_torture_wr Not tainted 5.19.0-rc3+ #1546\n[ 676.245216] Hardware name: Red Hat KVM/RHEL-AV, BIOS 1.16.0-2.module+el8.7.0+15506+033991b0 04/01/2014\n[ 676.246460] RIP: 0010:dlm_lowcomms_commit_msg+0x41/0x50\n[ 676.247132] Code: fe ff ff ff 75 24 48 c7 c6 bd 0f 49 bb 48 c7 c7 38 7c 01 bd e8 00 e7 ca ff 89 de 48 c7 c7 60 78 01 bd e8 42 3d cd ff 5b 5d c3 <0f> 0b eb d8 66 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 55 48\n[ 676.249253] RSP: 0018:ffffa401c18ffc68 EFLAGS: 00010282\n[ 676.249855] RAX: 0000000000000001 RBX: 00000000ffff8b76 RCX: 0000000000000006\n[ 676.250713] RDX: 0000000000000000 RSI: ffffffffbccf3a10 RDI: ffffffffbcc7b62e\n[ 676.251610] RBP: ffffa401c18ffc70 R08: 0000000000000001 R09: 0000000000000001\n[ 676.252481] R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000005\n[ 676.253421] R13: ffff8b76786ec370 R14: ffff8b76786ec370 R15: ffff8b76786ec480\n[ 676.254257] FS: 0000000000000000(0000) GS:ffff8b7777800000(0000) knlGS:0000000000000000\n[ 676.255239] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\n[ 676.255897] CR2: 00005590205d88b8 CR3: 000000017656c003 CR4: 0000000000770ee0\n[ 676.256734] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\n[ 676.257567] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\n[ 676.258397] PKRU: 55555554\n[ 676.258729] Call Trace:\n[ 676.259063] \n[ 676.259354] dlm_midcomms_commit_mhandle+0xcc/0x110\n[ 676.259964] queue_bast+0x8b/0xb0\n[ 676.260423] grant_pending_locks+0x166/0x1b0\n[ 676.261007] _unlock_lock+0x75/0x90\n[ 676.261469] unlock_lock.isra.57+0x62/0xa0\n[ 676.262009] dlm_unlock+0x21e/0x330\n[ 676.262457] ? lock_torture_stats+0x80/0x80 [dlm_locktorture]\n[ 676.263183] torture_unlock+0x5a/0x90 [dlm_locktorture]\n[ 676.263815] ? preempt_count_sub+0xba/0x100\n[ 676.264361] ? complete+0x1d/0x60\n[ 676.264777] lock_torture_writer+0xb8/0x150 [dlm_locktorture]\n[ 676.265555] kthread+0x10a/0x130\n[ 676.266007] ? kthread_complete_and_exit+0x20/0x20\n[ 676.266616] ret_from_fork+0x22/0x30\n[ 676.267097] \n[ 676.267381] irq event stamp: 9579855\n[ 676.267824] hardirqs last enabled at (9579863): [] __up_console_sem+0x58/0x60\n[ 676.268896] hardirqs last disabled at (9579872): [] __up_console_sem+0x3d/0x60\n[ 676.270008] softirqs last enabled at (9579798): [] __do_softirq+0x349/0x4c7\n[ 676.271438] softirqs last disabled at (9579897): [] irq_exit_rcu+0xb0/0xf0\n[ 676.272796] ---[ end trace 0000000000000000 ]---\n\nI reproduced this warning with dlm_locktorture test which is currently\nnot upstream. However this patch fix the issue by make a additional\nrefcount between dlm_lowcomms_new_msg() and dlm_lowcomms_commit_msg().\nIn case of the race the kref_put() in dlm_lowcomms_commit_msg() will be\nthe final put."
}
],
"metrics": [
{
"cvssV3_1": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
"baseScore": 9.8,
"baseSeverity": "CRITICAL"
},
"scenarios": [
{
"lang": "en",
"value": "AV:N - The race is hit when the local node commits outbound DLM messages (e.g. BASTs from grant_pending_locks), which remote peers induce by sending lock/unlock traffic over the DLM TCP/SCTP transport on port 21064; that is the same network-reachable midcomms/lowcomms path scored AV:N for related DLM CVEs.\nAC:L - A peer can drive both sides by flooding concurrent lock operations so many commit_msg calls race with the send workqueue that frees dlm_msg; the locktorture repro shows this is reliably hittable under attacker-controlled load rather than a one-shot environmental fluke.\nPR:N - DLM lowcomms has no authentication or TLS in the affected versions—only an IP-to-nodeid allowlist—so a cluster peer, compromised node, or address-spoofing attacker needs no account or privilege on the victim.\nUI:N - Crafted or concurrent peer lock messages are processed by DLM receive/send workqueues on an already-running cluster with no victim user action required.\nS:U - Corruption stays in host kernel memory (freed dlm_msg and SRCU per-CPU counters) within one security authority; no VM, IOMMU, or sandbox boundary is crossed.\nC:H - This is a use-after-free of a kmem_cache-backed dlm_msg; after free, msg->idx and related fields can be groomed/reused so subsequent reads of the stale object yield an attacker-steerable kernel read primitive.\nI:H - srcu_read_unlock() uses the freed msg->idx in this_cpu_inc(srcu_unlock_count[idx]) on a size-2 array, giving an out-of-bounds write when idx is garbage, which is exploitable for memory corruption and control-flow hijack as with the related midcomms UAF.\nA:H - The UAF produces WARN/oops paths (as in the reported srcu.h warning) and corrupted SRCU accounting that can panic, hang DLM, or take down the clustered filesystem node."
}
]
}
],
"affected": [
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "unaffected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"fs/dlm/lowcomms.c"
],
"versions": [
{
"version": "b38bc9c2b3171f4411d80015ecb876bc6f9bcd26",
"lessThan": "27d3e646dd83bafd7094890462eebfce3ac31e4a",
"status": "affected",
"versionType": "git"
},
{
"version": "b38bc9c2b3171f4411d80015ecb876bc6f9bcd26",
"lessThan": "eb97e60a9eae632ff9104a580dbc4fdc58dc23cb",
"status": "affected",
"versionType": "git"
},
{
"version": "b38bc9c2b3171f4411d80015ecb876bc6f9bcd26",
"lessThan": "de7fdff754bb4d01e38e19964c309b6df6a79472",
"status": "affected",
"versionType": "git"
},
{
"version": "b38bc9c2b3171f4411d80015ecb876bc6f9bcd26",
"lessThan": "30ea3257e8766027c4d8d609dcbd256ff9a76073",
"status": "affected",
"versionType": "git"
},
{
"version": "7ae861bbfa0f69bd36bdff47f9755ad67a2bd219",
"status": "affected",
"versionType": "git"
},
{
"version": "5.13.2",
"lessThan": "5.14",
"status": "affected",
"versionType": "semver"
}
]
},
{
"product": "Linux",
"vendor": "Linux",
"defaultStatus": "affected",
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"programFiles": [
"fs/dlm/lowcomms.c"
],
"versions": [
{
"version": "5.14",
"status": "affected"
},
{
"version": "0",
"lessThan": "5.14",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "5.15.75",
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "5.19.17",
"lessThanOrEqual": "5.19.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "6.0.3",
"lessThanOrEqual": "6.0.*",
"status": "unaffected",
"versionType": "semver"
},
{
"version": "6.1",
"lessThanOrEqual": "*",
"status": "unaffected",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"operator": "OR",
"negate": false,
"cpeMatch": [
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.14",
"versionEndExcluding": "5.15.75"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.14",
"versionEndExcluding": "5.19.17"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.14",
"versionEndExcluding": "6.0.3"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.14",
"versionEndExcluding": "6.1"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionStartIncluding": "5.13.2"
}
]
}
]
}
],
"references": [
{
"url": "https://git.kernel.org/stable/c/27d3e646dd83bafd7094890462eebfce3ac31e4a"
},
{
"url": "https://git.kernel.org/stable/c/eb97e60a9eae632ff9104a580dbc4fdc58dc23cb"
},
{
"url": "https://git.kernel.org/stable/c/de7fdff754bb4d01e38e19964c309b6df6a79472"
},
{
"url": "https://git.kernel.org/stable/c/30ea3257e8766027c4d8d609dcbd256ff9a76073"
}
],
"title": "fs: dlm: fix race in lowcomms",
"x_generator": {
"engine": "bippy-1.2.0"
}
},
"adp": [
{
"metrics": [
{
"cvssV3_1": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 4.7,
"attackVector": "LOCAL",
"baseSeverity": "MEDIUM",
"vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "HIGH",
"availabilityImpact": "HIGH",
"privilegesRequired": "LOW",
"confidentialityImpact": "NONE"
}
},
{
"other": {
"type": "ssvc",
"content": {
"id": "CVE-2022-50373",
"role": "CISA Coordinator",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"version": "2.0.3",
"timestamp": "2026-01-14T18:36:47.932587Z"
}
}
}
],
"problemTypes": [
{
"descriptions": [
{
"lang": "en",
"type": "CWE",
"cweId": "CWE-362",
"description": "CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')"
}
]
}
],
"title": "CISA ADP Vulnrichment",
"providerMetadata": {
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP",
"dateUpdated": "2026-01-14T18:43:00.519Z"
}
}
]
}
}