CVE-2023-53832: Linux

EPSS: 0.3% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: md/raid10: fix null-ptr-deref in raid10_sync_request init_resync() inits mempool and sets conf->have_replacemnt at the beginning of sync, close_sync() frees the mempool when sync is completed. After [1] recovery might be skipped and init_resync() is called but close_sync() is not. null-ptr-deref occurs with r10bio->dev[i].repl_bio. The following is one way to reproduce the issue. 1) create a array, wait for resync to complete, mddev->recovery_cp is set to MaxSector. 2) recovery is woken and it is skipped. conf->have_replacement is set to 0 in init_resync(). close_sync() not called. 3) some io errors and rdev A is set to WantReplacement. 4) a new device is added and set to A's replacement. 5) recovery is woken, A have replacement, but conf->have_replacemnt is 0. r10bio->dev[i].repl_bio will not be alloced and null-ptr-deref occurs. Fix it by not calling init_resync() if recovery skipped. [1] commit 7e83ccbecd60 ("md/raid10: Allow skipping recovery when clean arrays are assembled")

Affected products

• Linux Linux: from 3.10, before 4.19.283 (fixed in 4.19.283); from 4.20, before 5.4.243 (fixed in 5.4.243); from 5.5, before 5.10.180 (fixed in 5.10.180); from 5.11, before 5.15.111 (fixed in 5.15.111); from 5.16, before 6.1.28 (fixed in 6.1.28); from 6.2, before 6.2.15 (fixed in 6.2.15); …

Published 2025-12-09. Last modified 2026-06-17.