In the Linux kernel, the following vulnerability has been resolved: zram: fix out-of-bounds access in read_block_state() read_block_state() calculates nr_pages before taking dev_lock

Overview

In the Linux kernel, the following vulnerability has been resolved:

zram: fix out-of-bounds access in read_block_state()

read_block_state() calculates nr_pages before taking dev_lock. If the device is reset and reinitialized with a smaller disksize before lock acquisition, nr_pages still describes the old table. The subsequent loop can then call slot_lock() past the end of the newly allocated table.

Read disksize after acquiring dev_lock and checking that the device is initialized. The read lock then keeps the table and its bound stable for the duration of the scan.

Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

Vendor advisories

• Red Hat VEX · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · updated 2026-10-21 · vex