CVE-2022-49407: dlm: fix plock invalid read

Description

In the Linux kernel, the following vulnerability has been resolved: dlm: fix plock invalid read This patch fixes an invalid read showed by KASAN. A unlock will allocate a "struct plock_op" and a followed send_op() will append it to a global send_list data structure. In some cases a followed dev_read() moves it to recv_list and dev_write() will cast it to "struct plock_xop" and access fields which are only available in those structures. At this point an invalid read happens by accessing those fields. To fix this issue the "callback" field is moved to "struct plock_op" to indicate that a cast to "plock_xop" is allowed and does the additional "plock_xop" handling if set. Example of the KASAN output which showed the invalid read: [ 2064.296453] ================================================================== [ 2064.304852] BUG: KASAN: slab-out-of-bounds in dev_write+0x52b/0x5a0 [dlm] [ 2064.306491] Read of size 8 at addr ffff88800ef227d8 by task dlm_controld/7484 [ 2064.308168] [ 2064.308575] CPU: 0 PID: 7484 Comm: dlm_controld Kdump: loaded Not tainted 5.14.0+ #9 [ 2064.310292] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 [ 2064.311618] Call Trace: [ 2064.312218] dump_stack_lvl+0x56/0x7b [ 2064.313150] print_address_description.constprop.8+0x21/0x150 [ 2064.314578] ? dev_write+0x52b/0x5a0 [dlm] [ 2064.315610] ? dev_write+0x52b/0x5a0 [dlm] [ 2064.316595] kasan_report.cold.14+0x7f/0x11b [ 2064.317674] ? dev_write+0x52b/0x5a0 [dlm] [ 2064.318687] dev_write+0x52b/0x5a0 [dlm] [ 2064.319629] ? dev_read+0x4a0/0x4a0 [dlm] [ 2064.320713] ? bpf_lsm_kernfs_init_security+0x10/0x10 [ 2064.321926] vfs_write+0x17e/0x930 [ 2064.322769] ? __fget_light+0x1aa/0x220 [ 2064.323753] ksys_write+0xf1/0x1c0 [ 2064.324548] ? __ia32_sys_read+0xb0/0xb0 [ 2064.325464] do_syscall_64+0x3a/0x80 [ 2064.326387] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 2064.327606] RIP: 0033:0x7f807e4ba96f [ 2064.328470] Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 39 87 f8 ff 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 7c 87 f8 ff 48 [ 2064.332902] RSP: 002b:00007ffd50cfe6e0 EFLAGS: 00000293 ORIG_RAX: 0000000000000001 [ 2064.334658] RAX: ffffffffffffffda RBX: 000055cc3886eb30 RCX: 00007f807e4ba96f [ 2064.336275] RDX: 0000000000000040 RSI: 00007ffd50cfe7e0 RDI: 0000000000000010 [ 2064.337980] RBP: 00007ffd50cfe7e0 R08: 0000000000000000 R09: 0000000000000001 [ 2064.339560] R10: 000055cc3886eb30 R11: 0000000000000293 R12: 000055cc3886eb80 [ 2064.341237] R13: 000055cc3886eb00 R14: 000055cc3886f590 R15: 0000000000000001 [ 2064.342857] [ 2064.343226] Allocated by task 12438: [ 2064.344057] kasan_save_stack+0x1c/0x40 [ 2064.345079] __kasan_kmalloc+0x84/0xa0 [ 2064.345933] kmem_cache_alloc_trace+0x13b/0x220 [ 2064.346953] dlm_posix_unlock+0xec/0x720 [dlm] [ 2064.348811] do_lock_file_wait.part.32+0xca/0x1d0 [ 2064.351070] fcntl_setlk+0x281/0xbc0 [ 2064.352879] do_fcntl+0x5e4/0xfe0 [ 2064.354657] __x64_sys_fcntl+0x11f/0x170 [ 2064.356550] do_syscall_64+0x3a/0x80 [ 2064.358259] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 2064.360745] [ 2064.361511] Last potentially related work creation: [ 2064.363957] kasan_save_stack+0x1c/0x40 [ 2064.365811] __kasan_record_aux_stack+0xaf/0xc0 [ 2064.368100] call_rcu+0x11b/0xf70 [ 2064.369785] dlm_process_incoming_buffer+0x47d/0xfd0 [dlm] [ 2064.372404] receive_from_sock+0x290/0x770 [dlm] [ 2064.374607] process_recv_sockets+0x32/0x40 [dlm] [ 2064.377290] process_one_work+0x9a8/0x16e0 [ 2064.379357] worker_thread+0x87/0xbf0 [ 2064.381188] kthread+0x3ac/0x490 [ 2064.383460] ret_from_fork+0x22/0x30 [ 2064.385588] [ 2064.386518] Second to last potentially related work creation: [ 2064.389219] kasan_save_stack+0x1c/0x40 [ 2064.391043] __kasan_record_aux_stack+0xaf/0xc0 [ 2064.393303] call_rcu+0x11b/0xf70 [ 2064.394885] dlm_process_incoming_buffer+0x47d/0xfd0 [dlm] [ 2064.397694] receive_from_sock+0x290/0x770 ---truncated---

Scores

CVSS scores of CVE-2022-49407, by who scored it
Scored by	CVSS	Score	Vector
LinuxCNA (assigner)	3.1	Critical9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVDNVD · Modified	3.1	High7.1	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

EPSS (exploitation in 30 days): 0.87% · top 41% of all CVEs (7 Nov 2026)
CISA SSVC: Exploitation: none · Automatable: yes · Technical impact: total

The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.

Weakness

CWE-125 (opens in a new tab)All about CWE-125 and its CVEs

Affected products

Linux · Linux
- affected 586759f03e2e9031ac5589912a51a909ed53c30a – < 2c55155cc365861044d9e6e80e342693e8805e33
- affected 586759f03e2e9031ac5589912a51a909ed53c30a – < 72f2f68970f9bdc252d59e119b385a6441b0b155
- affected 586759f03e2e9031ac5589912a51a909ed53c30a – < 5a1765adf9855cf0f6d3f7e0eb4b78ca66f70dee
- affected 586759f03e2e9031ac5589912a51a909ed53c30a – < 49cd9eb7b9a7b88124b31e31f8e539acaf1b3a6d
- affected 586759f03e2e9031ac5589912a51a909ed53c30a – < 899bc4429174861122f0c236588700a4710c1fec
- affected 586759f03e2e9031ac5589912a51a909ed53c30a – < acdad5bc9827922ec2f2e84fd198718aa8e8ab92
- affected 586759f03e2e9031ac5589912a51a909ed53c30a – < 56aa8d1fbd02357f3bf81bdfba1cde87ce8402fc
- affected 586759f03e2e9031ac5589912a51a909ed53c30a – < e421872fa17542cf33747071fb141b0130ce9ef7
- affected 586759f03e2e9031ac5589912a51a909ed53c30a – < 42252d0d2aa9b94d168241710a761588b3959019
Linux · Linux
- affected 2.6.22
- unaffected < 2.6.22
- unaffected 4.9.318 – ≤ 4.9.*
- unaffected 4.14.283 – ≤ 4.14.*
- unaffected 4.19.247 – ≤ 4.19.*
- unaffected 5.4.198 – ≤ 5.4.*
- unaffected 5.10.121 – ≤ 5.10.*
- unaffected 5.15.46 – ≤ 5.15.*
- unaffected 5.17.14 – ≤ 5.17.*
- unaffected 5.18.3 – ≤ 5.18.*
- unaffected 5.19 – ≤ *

References (9)

Sources

The same CVE in the primary databases and aggregators, to check against.

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Record last updated 15 Oct 2026, 21:21 UTC.