CVE-2026-68460: f2fs: fix potential deadlock in f2fs_balance_fs()
In the Linux kernel, the following vulnerability has been resolved:
f2fs: fix potential deadlock in f2fsbalancefs()
When the f2fs filesystem space is nearly exhausted, we encounter deadlock issues as below:
INFO: task A:1890 blocked for more than 120 seconds. Tainted: G O 6.12.41-g3fe07ddf05ab #1 "echo 0 > /proc/sys/kernel/hungtasktimeoutsecs" disables this message. task:A state:D stack:0 pid:1890 tgid:1626 ppid:1153 flags:0x00000204 Call trace: switchto+0xf4/0x158 schedule+0x27c/0x908 schedule+0x3c/0x118 ioschedule+0x44/0x68 foliowaitbitcommon+0x174/0x370 foliowaitbit+0x20/0x38 foliowaitwriteback+0x54/0xc8 truncateinodepartialfolio+0x70/0x1e0 truncateinodepagesrange+0x1b0/0x450 truncatepagecache+0x54/0x88 f2fsfilewriteiter+0x3e8/0xb80 doiterreadvwritev+0xf0/0x1e0 vfswritev+0x138/0x2c8 dowritev+0x88/0x130 arm64syswritev+0x28/0x40 invokesyscall+0x50/0x120 el0svccommon.constprop.0+0xc8/0xf0 doel0svc+0x24/0x38 el0svc+0x30/0xf8 el0t64synchandler+0x120/0x130 el0t64sync+0x190/0x198
INFO: task kworker/u8:11:2680853 blocked for more than 120 seconds. Tainted: G O 6.12.41-g3fe07ddf05ab #1 "echo 0 > /proc/sys/kernel/hungtasktimeoutsecs" disables this message. task:kworker/u8:11 state:D stack:0 pid:2680853 tgid:2680853 ppid:2 flags:0x00000208 Workqueue: writeback wbworkfn (flush-254:0) Call trace: switchto+0xf4/0x158 schedule+0x27c/0x908 schedule+0x3c/0x118 ioschedule+0x44/0x68 foliowaitbitcommon+0x174/0x370 filemapgetfolio+0x214/0x348 pagecachegetpage+0x20/0x70 f2fsgetreaddatapage+0x150/0x3e8 f2fsgetlockdatapage+0x2c/0x160 movedatapage+0x50/0x478 dogarbagecollect+0xd38/0x1528 f2fsgc+0x240/0x7e0 f2fsbalancefs+0x1a0/0x208 f2fswritesingledatapage+0x6e4/0x730 f2fswritecachepages+0x378/0x9b0 f2fswritedatapages+0x2e4/0x388 dowritepages+0x8c/0x2c8 writebacksingleinode+0x4c/0x498 writebacksbinodes+0x234/0x4a8 writebackinodeswb+0x58/0x118 wbwriteback+0x2f8/0x3c0 wbworkfn+0x2c4/0x508 processonework+0x180/0x408 workerthread+0x258/0x368 kthread+0x118/0x128 retfromfork+0x10/0x200
INFO: task kworker/u8:8:2641297 blocked for more than 120 seconds. Tainted: G O 6.12.41-g3fe07ddf05ab #1 "echo 0 > /proc/sys/kernel/hungtasktimeoutsecs" disables this message. task:kworker/u8:8 state:D stack:0 pid:2641297 tgid:2641297 ppid:2 flags:0x00000208 Workqueue: writeback wbworkfn (flush-254:0) Call trace: switchto+0xf4/0x158 schedule+0x27c/0x908 rtmutexschedule+0x30/0x60 rtmutexslowlocklocked.constprop.0+0x460/0x8a8 rwbasewritelock+0x24c/0x378 downwrite+0x1c/0x30 f2fsbalancefs+0x184/0x208 f2fswriteinode+0xf4/0x328 writebacksingleinode+0x370/0x498 writebacksbinodes+0x234/0x4a8 writebackinodeswb+0x58/0x118 wbwriteback+0x2f8/0x3c0 wbworkfn+0x2c4/0x508 processonework+0x180/0x408 workerthread+0x258/0x368 kthread+0x118/0x128 retfromfork+0x10/0x20
INFO: task B:1902 blocked for more than 120 seconds. Tainted: G O 6.12.41-g3fe07ddf05ab #1 "echo 0 > /proc/sys/kernel/hungtasktimeoutsecs" disables this message. task:B state:D stack:0 pid:1902 tgid:1626 ppid:1153 flags:0x0000020c Call trace: switchto+0xf4/0x158 schedule+0x27c/0x908 rtmutexschedule+0x30/0x60 rtmutexslowlocklocked.constprop.0+0x460/0x8a8 rwbasewritelock+0x24c/0x378 downwrite+0x1c/0x30 f2fsbalancefs+0x184/0x208 f2fsmapblocks+0x94c/0x1110 f2fsfilewriteiter+0x228/0xb80 doiterreadvwritev+0xf0/0x1e0 vfswritev+0x138/0x2c8 dowritev+0x88/0x130 arm64syswritev+0x28/0x40 invokesyscall+0x50/0x120 el0svccommon.constprop.0+0xc8/0xf0 doel0svc+0x24/0x38 el0svc+0x30/0xf8 el0t64synchandler+0x120/0x130 el0t64sync+0x190/0x198
INFO: task sync:2769849 blocked for more than 120 seconds. Tainted: G ---truncated---
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 6.12.41-g3fe07ddf05ab - Configuration
Set /proc/sys/kernel/hung_task_timeout_secs to 0 (e.g., `echo 0 > /proc/sys/kernel/hung_task_timeout_secs`) to disable the hung-task message shown in the log.
Linux kernel sysctl kernel.hung_task_timeout_secs = 0
Event History
Frequently Asked Questions
What is the severity of CVE-2026-68460?
CVE-2026-68460 has a risk score of 23, indicating a significant severity and potential impact.
What systems are affected by CVE-2026-68460?
CVE-2026-68460 affects the Linux kernel with the f2fs filesystem.
How do I fix CVE-2026-68460?
To fix CVE-2026-68460, update your Linux kernel to the latest version that includes the patch.
What is the vulnerability in CVE-2026-68460 about?
CVE-2026-68460 addresses a potential deadlock issue in the f2fs filesystem when disk space is nearly exhausted.
When was CVE-2026-68460 published?
CVE-2026-68460 was published on August 15, 2026.