CVE-2022-49297 | nbd: fix io hung while disconnecting device

In the Linux kernel, the following vulnerability has been resolved: nbd: fix io hung while disconnecting device In our tests, "qemu-nbd" triggers a io hung: INFO: task qemu-nbd:11445 blocked for more than 368 seconds. Not tainted 5.18.0-rc3-next-20220422-00003-g2176915513ca #884 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:qemu-nbd state:D stack: 0 pid:11445 ppid: 1 flags:0x00000000 Call Trace: <TASK> __schedule+0x480/0x1050 ? _raw_spin_lock_irqsave+0x3e/0xb0 schedule+0x9c/0x1b0 blk_mq_freeze_queue_wait+0x9d/0xf0 ? ipi_rseq+0x70/0x70 blk_mq_freeze_queue+0x2b/0x40 nbd_add_socket+0x6b/0x270 [nbd] nbd_ioctl+0x383/0x510 [nbd] blkdev_ioctl+0x18e/0x3e0 __x64_sys_ioctl+0xac/0x120 do_syscall_64+0x35/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7fd8ff706577 RSP: 002b:00007fd8fcdfebf8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000040000000 RCX: 00007fd8ff706577 RDX: 000000000000000d RSI: 000000000000ab00 RDI: 000000000000000f RBP: 000000000000000f R08: 000000000000fbe8 R09: 000055fe497c62b0 R10: 00000002aff20000 R11: 0000000000000246 R12: 000000000000006d R13: 0000000000000000 R14: 00007ffe82dc5e70 R15: 00007fd8fcdff9c0 "qemu-ndb -d" will call ioctl 'NBD_DISCONNECT' first, however, following message was found: block nbd0: Send disconnect failed -32 Which indicate that something is wrong with the server. Then, "qemu-nbd -d" will call ioctl 'NBD_CLEAR_SOCK', however ioctl can't clear requests after commit 2516ab1543fd("nbd: only clear the queue on device teardown"). And in the meantime, request can't complete through timeout because nbd_xmit_timeout() will always return 'BLK_EH_RESET_TIMER', which means such request will never be completed in this situation. Now that the flag 'NBD_CMD_INFLIGHT' can make sure requests won't complete multiple times, switch back to call nbd_clear_sock() in nbd_clear_sock_ioctl(), so that inflight requests can be cleared.

Published: 2025-02-26 Last update: 2025-10-21 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2022-49297 is rated Low Risk (28.7/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.27%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2022-49297

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.03% 0.27% +0.24%
2 2025-10-22 0.08% 0.03% -0.06%
3 2025-03-17 — 0.08% —

Full EPSS history (4 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2022-49297

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 3.6 [email protected]

Weakness enumeration for CVE-2022-49297

OS Trackers for CVE-2022-49297

vendor priority summary link
debian not yet assigned CVE-2022-49297 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2022-49297
redhat low — https://access.redhat.com/security/cve/CVE-2022-49297
suse medium — https://www.suse.com/security/cve/CVE-2022-49297/
ubuntu medium CVE-2022-49297 medium priority: Ubuntu including 158 source packages (linux, linux-allwinner-5.19, …), 1551 status rows across 10 suites (bionic, focal, jammy, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 1145, released 150, ignored 149, not-affected 102, needed 5. https://ubuntu.com/security/CVE-2022-49297

Affected software / configurations for CVE-2022-49297

Vendor Product Version Raw CPE
linux linux_kernel < 4.14.283 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 4.15, < 4.19.247 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 4.20, < 5.4.198 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.5, < 5.10.122 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.11, < 5.15.47 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.16, < 5.17.15 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
linux linux_kernel >= 5.18, < 5.18.4 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

References for CVE-2022-49297

cvelogic Threat Intelligence