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.
CVSS Details
- CVSS 3.1 Base Score: 7.8
- CVSS 3.1 Vector: (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Amazon Linux Ami 2 | — | Upgrade kernel-develUpgrade perfUpgrade kernelUpgrade kernel-headersUpgrade kernel-tools-debuginfoUpgrade kernel-tools-develUpgrade bpftoolUpgrade kernel-debuginfoUpgrade kernel-debuginfo-common-aarch64Upgrade kernel-livepatch-5.15.86-53.137Upgrade perf-debuginfoUpgrade kernel-toolsUpgrade kernel-livepatch-4.14.304-226.531Upgrade python-perfUpgrade kernel-livepatch-5.10.165-143.735Upgrade kernel-debuginfo-common-x86_64Upgrade bpftool-debuginfoUpgrade python-perf-debuginfo | May 20, 2026 | May 20, 2026 |
| Debian | — | Upgrade linux | Dec 29, 2025 | Dec 29, 2025 |
| Huawei Euleros 2_0_sp10 | — | Upgrade python3-perfUpgrade kernelUpgrade kernel-abi-stablelistsUpgrade kernel-toolsUpgrade kernel-tools-libs | Mar 17, 2026 | Mar 16, 2026 |
| Huawei Euleros 2_0_sp13 | — | Upgrade kernelUpgrade kernel-toolsUpgrade python3-perfUpgrade kernel-tools-libsUpgrade bpftoolUpgrade kernel-abi-stablelists | Mar 10, 2026 | Mar 10, 2026 |
| Redhat_linux | — | No solution exists | Jul 17, 2026 | Dec 24, 2025 |
| Ubuntu | — | Upgrade linux-oracle-5.15Upgrade linux-hwe-5.15Upgrade linux-raspiUpgrade linux-raspi-5.4Upgrade linux-fipsUpgrade linux-realtimeUpgrade linux-aws-5.4Upgrade linux-lowlatency-hwe-5.15Upgrade linux-aws-hweUpgrade linux-aws-5.15Upgrade linux-riscv-5.15Upgrade linux-gkeUpgrade linux-intel-iotgUpgrade linux-azureUpgrade linux-awsUpgrade linux-nvidia-tegra-5.15Upgrade linux-bluefieldUpgrade linux-oracle-5.4Upgrade linux-lowlatencyUpgrade linux-oracleUpgrade linux-gcp-5.4Upgrade linux-gkeopUpgrade linux-gcp-fipsUpgrade linux-gcpUpgrade linux-gcp-4.15Upgrade linux-ibm-5.4Upgrade linux-azure-fipsUpgrade linux-kvmUpgrade linux-azure-5.4Upgrade linux-xilinx-zynqmpUpgrade linux-gcp-5.15Upgrade linux-iotUpgrade linux-hweUpgrade linuxUpgrade linux-azure-4.15Upgrade linux-ibmUpgrade linux-azure-5.15Upgrade linux-intel-iot-realtimeUpgrade linux-nvidiaUpgrade linux-intel-iotg-5.15Upgrade linux-aws-fipsUpgrade linux-hwe-5.4 | Jan 6, 2026 | Dec 24, 2025 |
| Vmware Photon_os | — | Use 'tdnf update' to upgrade all packages to the latest version. | May 27, 2026 | Dec 24, 2025 |
Prioritise with Active Threat Intelligence
With curated Threat Intelligence, you can see which vulnerabilities truly put you at risk, prioritize what matters most, and act before attackers do.
Explore Intelligence Hub