CVE-2022-50755 | udf: Avoid double brelse() in udf_rename()

In the Linux kernel, the following vulnerability has been resolved: udf: Avoid double brelse() in udf_rename() syzbot reported a warning like below [1]: VFS: brelse: Trying to free free buffer WARNING: CPU: 2 PID: 7301 at fs/buffer.c:1145 __brelse+0x67/0xa0 ... Call Trace: <TASK> invalidate_bh_lru+0x99/0x150 smp_call_function_many_cond+0xe2a/0x10c0 ? generic_remap_file_range_prep+0x50/0x50 ? __brelse+0xa0/0xa0 ? __mutex_lock+0x21c/0x12d0 ? smp_call_on_cpu+0x250/0x250 ? rcu_read_lock_sched_held+0xb/0x60 ? lock_release+0x587/0x810 ? __brelse+0xa0/0xa0 ? generic_remap_file_range_prep+0x50/0x50 on_each_cpu_cond_mask+0x3c/0x80 blkdev_flush_mapping+0x13a/0x2f0 blkdev_put_whole+0xd3/0xf0 blkdev_put+0x222/0x760 deactivate_locked_super+0x96/0x160 deactivate_super+0xda/0x100 cleanup_mnt+0x222/0x3d0 task_work_run+0x149/0x240 ? task_work_cancel+0x30/0x30 do_exit+0xb29/0x2a40 ? reacquire_held_locks+0x4a0/0x4a0 ? do_raw_spin_lock+0x12a/0x2b0 ? mm_update_next_owner+0x7c0/0x7c0 ? rwlock_bug.part.0+0x90/0x90 ? zap_other_threads+0x234/0x2d0 do_group_exit+0xd0/0x2a0 __x64_sys_exit_group+0x3a/0x50 do_syscall_64+0x34/0xb0 entry_SYSCALL_64_after_hwframe+0x63/0xcd The cause of the issue is that brelse() is called on both ofibh.sbh and ofibh.ebh by udf_find_entry() when it returns NULL. However, brelse() is called by udf_rename(), too. So, b_count on buffer_head becomes unbalanced. This patch fixes the issue by not calling brelse() by udf_rename() when udf_find_entry() returns NULL.

Published: 2025-12-24 Last update: 2026-04-15 Assigner: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Conclusion & alert: CVE-2022-50755 is rated Low Risk (19.7/100): low exploitation likelihood (EPSS 0.06%). Mandatory action: Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.

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-2022-50755

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 2026-04-25 0.03% 0.06% +0.03%
2 2025-12-25 0.03%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2022-50755

CVSS metrics for this CVE.

No CVSS data in dataset for this CVE.

Weakness enumeration for CVE-2022-50755

OS Trackers for CVE-2022-50755

vendor priority summary link
debian not yet assigned CVE-2022-50755 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-2022-50755
redhat low https://access.redhat.com/security/cve/CVE-2022-50755
suse medium https://www.suse.com/security/cve/CVE-2022-50755/
ubuntu medium CVE-2022-50755 medium priority: Ubuntu including 157 source packages (linux, linux-allwinner-5.19, …), 1405 status rows across 9 suites (bionic, focal, jammy, noble, plucky, questing, trusty, upstream, xenial): DNE 1010, ignored 176, released 145, not-affected 68, needed 5, needs-triage 1. https://ubuntu.com/security/CVE-2022-50755

Affected software / configurations for CVE-2022-50755

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2022-50755

cvelogic Threat Intelligence