CVE-2026-31457

In the Linux kernel, the following vulnerability has been resolved: mm/damon/sysfs: check contexts->nr in repeat_call_fn damon_sysfs_repeat_call_fn() calls damon_sysfs_upd_tuned_intervals(), damon_sysfs_upd_schemes_stats(), and damon_sysfs_upd_schemes_effective_quotas() without checking contexts->nr. If nr_contexts is set to 0 via sysfs while DAMON is running, these functions dereference contexts_arr[0] and cause a NULL pointer dereference. Add the missing check. For example, the issue can be reproduced using DAMON sysfs interface and DAMON user-space tool (damo) [1] like below. $ sudo damo start --refresh_interval 1s $ echo 0 | sudo tee \ /sys/kernel/mm/damon/admin/kdamonds/0/contexts/nr_contexts

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/3527e9fdc38570cea0f6ddb7a2c9303d4044b217	Patch
https://git.kernel.org/stable/c/652cd0641a763dd0e846b0d12814977fadb2b7d8	Patch
https://git.kernel.org/stable/c/6557004a8b59c7701e695f02be03c7e20ed1cc15	Patch

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc1::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc2::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc3::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc4::::::
	cpe:2.3:o:linux:linux_kernel:7.0:rc5::::::

History

No history.

Information

Published : 2026-04-22 14:16

Updated : 2026-06-17 10:33

NVD link : CVE-2026-31457

Mitre link : CVE-2026-31457

CVE.ORG link : CVE-2026-31457

JSON object : View

Products Affected

linux

linux_kernel

CWE

CWE-476

NULL Pointer Dereference

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