mm/damon/sysfs: check contexts->nr before accessing contexts_arr[0]

MITRE NVD CVE.ORG JSON API Print: PDF PDF

Summary

CVECVE-2026-31458
StatePUBLISHED
AssignerLinux
Source PriorityCVE Program / NVD first with legacy fallback
Published2026-04-22 14:16:41 UTC
Updated2026-04-22 14:16:41 UTC
DescriptionIn the Linux kernel, the following vulnerability has been resolved: mm/damon/sysfs: check contexts->nr before accessing contexts_arr[0] Multiple sysfs command paths dereference contexts_arr[0] without first verifying that kdamond->contexts->nr == 1. A user can set nr_contexts to 0 via sysfs while DAMON is running, causing NULL pointer dereferences. In more detail, the issue can be triggered by privileged users like below. First, start DAMON and make contexts directory empty (kdamond->contexts->nr == 0). # damo start # cd /sys/kernel/mm/damon/admin/kdamonds/0 # echo 0 > contexts/nr_contexts Then, each of below commands will cause the NULL pointer dereference. # echo update_schemes_stats > state # echo update_schemes_tried_regions > state # echo update_schemes_tried_bytes > state # echo update_schemes_effective_quotas > state # echo update_tuned_intervals > state Guard all commands (except OFF) at the entry point of damon_sysfs_handle_cmd().

Vendor Declared Affected Products

SourceVendorProductVersionPlatforms
CNA Linux Linux affected 0ac32b8affb5a384253dbb8339bd2d0e91add0b7 aba546061341b56e9ffb37e1eb661a3628b6ec12 git Not specified
CNA Linux Linux affected 0ac32b8affb5a384253dbb8339bd2d0e91add0b7 1e8da792672481d603fa7cd0d815577220a3ee27 git Not specified
CNA Linux Linux affected 0ac32b8affb5a384253dbb8339bd2d0e91add0b7 708033c231bd782858f4ddbb46ee874a5a5fbdab git Not specified
CNA Linux Linux affected 0ac32b8affb5a384253dbb8339bd2d0e91add0b7 bbe03ad3fb9e714191757ca7b41582f930be7be2 git Not specified
CNA Linux Linux affected 0ac32b8affb5a384253dbb8339bd2d0e91add0b7 1bfe9fb5ed2667fb075682408b776b5273162615 git Not specified
CNA Linux Linux affected 5.18 Not specified
CNA Linux Linux unaffected 5.18 semver Not specified
CNA Linux Linux unaffected 6.6.131 6.6.* semver Not specified
CNA Linux Linux unaffected 6.12.80 6.12.* semver Not specified
CNA Linux Linux unaffected 6.18.21 6.18.* semver Not specified
CNA Linux Linux unaffected 6.19.11 6.19.* semver Not specified
CNA Linux Linux unaffected 7.0 * original_commit_for_fix Not specified

References

ReferenceSourceLinkTags
git.kernel.org/stable/c/708033c231bd782858f4ddbb46ee874a5a5fbdab 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/1bfe9fb5ed2667fb075682408b776b5273162615 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/aba546061341b56e9ffb37e1eb661a3628b6ec12 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/1e8da792672481d603fa7cd0d815577220a3ee27 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
git.kernel.org/stable/c/bbe03ad3fb9e714191757ca7b41582f930be7be2 416baaa9-dc9f-4396-8d5f-8c081fb06d67 git.kernel.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis
© CVE.report 2026 |

Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. It is the responsibility of user to evaluate the accuracy, completeness or usefulness of any information, opinion, advice or other content. EACH USER WILL BE SOLELY RESPONSIBLE FOR ANY consequences of his or her direct or indirect use of this web site. ALL WARRANTIES OF ANY KIND ARE EXPRESSLY DISCLAIMED. This site will NOT BE LIABLE FOR ANY DIRECT, INDIRECT or any other kind of loss.

CVE, CWE, and OVAL are registred trademarks of The MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. This site includes MITRE data granted under the following license.

Free CVE JSON API cve.report/api

CVE.report and Source URL Uptime Status status.cve.report