CVE-2022-50457 mtd: core: Fix refcount error in del_mtd_device()

Medium 5.5 Published 1 Oct 2025 Updated 11 May 2026

A refcount leak in the Linux kernel MTD subsystem can lead to memory exhaustion and denial of service.

Exploited in the wild: Not known
Login needed: Any signed-in user
Attackable: Local or same network only
Victim action needed: Not needed
Fix: Available

What is CVE-2022-50457?

CVE-2022-50457 is a medium-severity memory corruption vulnerability in Linux kernel, published on 1 Oct 2025. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

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

mtd: core: Fix refcount error in del_mtd_device()

del_mtd_device() will call of_node_put() to mtd_get_of_node(mtd), which is mtd->dev.of_node. However, memset(&mtd->dev, 0) is called before of_node_put(). As the result, of_node_put() won't do anything in del_mtd_device(), and causes the refcount leak.

del_mtd_device() memset(&mtd->dev, 0, sizeof(mtd->dev) # clear mtd->dev of_node_put() mtd_get_of_node(mtd) # mtd->dev is cleared, can't locate of_node # of_node_put(NULL) won't do anything

Fix the error by caching the pointer of the device_node.

OF: ERROR: memory leak, expected refcount 1 instead of 2, of_node_get()/of_node_put() unbalanced - destroy cset entry: attach overlay node /spi/spi-sram@0 CPU: 3 PID: 275 Comm: python3 Tainted: G N 6.1.0-rc3+ #54 0d8a1edddf51f172ff5226989a7565c6313b08e2 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014 Call Trace: <TASK> dump_stack_lvl+0x67/0x83 kobject_get+0x155/0x160 of_node_get+0x1f/0x30 of_fwnode_get+0x43/0x70 fwnode_handle_get+0x54/0x80 fwnode_get_nth_parent+0xc9/0xe0 fwnode_full_name_string+0x3f/0xa0 device_node_string+0x30f/0x750 pointer+0x598/0x7a0 vsnprintf+0x62d/0x9b0 ... cfs_overlay_release+0x30/0x90 config_item_release+0xbe/0x1a0 config_item_put+0x5e/0x80 configfs_rmdir+0x3bd/0x540 vfs_rmdir+0x18c/0x320 do_rmdir+0x198/0x330 __x64_sys_rmdir+0x2c/0x40 do_syscall_64+0x37/0x90 entry_SYSCALL_64_after_hwframe+0x63/0xcd

[<[email protected]>: Light reword of the commit log]

Which versions are affected by CVE-2022-50457?

It affects 1 product.

Products include Linux kernel.

How do I fix CVE-2022-50457?

Apply the vendor's patch.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2022-50457 being exploited?

There is no known exploitation of CVE-2022-50457 in the wild and no public exploit code.

All Linux kernel vulnerabilities

Sources

Also known as DEBIAN-CVE-2022-50457, GHSA-j49h-xgx7-8459, UBUNTU-CVE-2022-50457.