CVE-2024-49854: block, bfq: fix uaf for accessing waker_bfqq after splitting

First published: Mon Oct 21 2024(Updated: )

In the Linux kernel, the following vulnerability has been resolved: block, bfq: fix uaf for accessing waker_bfqq after splitting After commit 42c306ed7233 ("block, bfq: don't break merge chain in bfq_split_bfqq()"), if the current procress is the last holder of bfqq, the bfqq can be freed after bfq_split_bfqq(). Hence recored the bfqq and then access bfqq->waker_bfqq may trigger UAF. What's more, the waker_bfqq may in the merge chain of bfqq, hence just recored waker_bfqq is still not safe. Fix the problem by adding a helper bfq_waker_bfqq() to check if bfqq->waker_bfqq is in the merge chain, and current procress is the only holder.

Credit: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Never miss a vulnerability like this again

Sign up to SecAlerts for real-time vulnerability data matched to your software, aggregated from hundreds of sources.

Read MoreStart Free Trial

• agent/title
• agent/references
• agent/type
• agent/description
• agent/first-publish-date
• agent/author
• agent/event
• agent/severity
• agent/remedy
• agent/weakness
• agent/softwarecombine
• collector/mitre-cve
• source/MITRE
• agent/last-modified-date
• agent/source
• agent/tags
• collector/nvd-api
• source/NVD
• agent/software-canonical-lookup
• agent/software-canonical-lookup-request
• vendor/linux
• canonical/linux kernel
• version/linux kernel/5.10.227
• version/linux kernel/5.16
• version/linux kernel/6.2
• version/linux kernel/6.7
• version/linux kernel/6.11