dm cache: fix flushing uninitialized delayed_work on cache_ctr error

Summary

In the Linux kernel, the following vulnerability has been resolved: dm cache: fix flushing uninitialized delayed_work on cache_ctr error An unexpected WARN_ON from flush_work() may occur when cache creation fails, caused by destroying the uninitialized delayed_work waker in the error path of cache_create(). For example, the warning appears on the superblock checksum error. Reproduce steps: dmsetup create cmeta --table "0 8192 linear /dev/sdc 0" dmsetup create cdata --table "0 65536 linear /dev/sdc 8192" dmsetup create corig --table "0 524288 linear /dev/sdc 262144" dd if=/dev/urandom of=/dev/mapper/cmeta bs=4k count=1 oflag=direct dmsetup create cache --table "0 524288 cache /dev/mapper/cmeta \ /dev/mapper/cdata /dev/mapper/corig 128 2 metadata2 writethrough smq 0" Kernel logs: (snip) WARNING: CPU: 0 PID: 84 at kernel/workqueue.c:4178 __flush_work+0x5d4/0x890 Fix by pulling out the cancel_delayed_work_sync() from the constructor's error path. This patch doesn't affect the use-after-free fix for concurrent dm_resume and dm_destroy (commit 6a459d8edbdb ("dm cache: Fix UAF in destroy()")) as cache_dtr is not changed.

Timeline

1. Nov 19, 2024, 1:30 AM UTCCVE published
2. Dec 11, 2024, 2:25 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: no · Technical impact: total

3. May 23, 2026, 3:54 PM UTCRecord last updated

Affected versions

• Linux Linux

  From 5.10.163 · fixed in 5.10.237; From 5.15.87 · fixed in 5.15.181; From 6.1.4 · fixed in 6.1.117; From 4.9.337 · fixed in 4.10; From 4.14.303 · fixed in 4.15; From 4.19.270 · fixed in 4.20; From 5.4.229 · fixed in 5.5; From 6.0.18 · fixed in 6.1

• Linux Linux

  6.2

References 6