Linux KernelOperating system · Linux
CVE-2022-49090
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedIn the Linux kernel, the following vulnerability has been resolved: arch/arm64: Fix topology initialization for core scheduling Arm64 systems rely on store_cpu_topology() to call update_siblings_masks() to transfer the toplogy to the various cpu masks. This needs to be done before the call to notify_cpu_starting() which tells the scheduler about each cpu found, otherwise the core scheduling data structures are setup in a way that does not match the actual topology. With smt_mask not setup correctly we bail on `cpumask_weight(smt_mask) == 1` for !leaders in: notify_cpu_starting() cpuhp_invoke_callback_range() sched_cpu_starting() sched_core_cpu_starting() which leads to rq->core not being correctly set for !leader-rq's. Without this change stress-ng (which enables core scheduling in its prctl tests in newer versions -- i.e. with PR_SCHED_CORE support) causes a warning and then a crash (trimmed for legibility): [ 1853.805168] ------------[ cut here ]------------ [ 1853.809784] task_rq(b)->core != rq->core [ 1853.809792] WARNING: CPU: 117 PID: 0 at kernel/sched/fair.c:11102 cfs_prio_less+0x1b4/0x1c4 ... [ 1854.015210] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000010 ... [ 1854.231256] Call trace: [ 1854.233689] pick_next_task+0x3dc/0x81c [ 1854.237512] __schedule+0x10c/0x4cc [ 1854.240988] schedule_idle+0x34/0x54
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysisThe code follows a pointer that is null, crashing the process. An attacker who can reliably trigger it turns the crash into a denial of service. The fix is checking for null before use and handling the failure path gracefully.
General guidance for the null pointer dereference class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data
Linux KernelOperating system
>= 5.14, < 5.15.34>= 5.16, < 5.16.20>= 5.17, < 5.17.3= 5.18CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Local
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped5.15.345.16.205.17.3
Linux Kernel 5.15.34 (or 5.16.20, 5.17.3, 5.18.1+, or 5.19+)
- 1. Identify the current kernel version using `uname -r`
- 2. For RHEL/CentOS systems: Update kernel via `yum update kernel` or `dnf update kernel`, then reboot
- 3. For Debian/Ubuntu systems: Update kernel via `apt update && apt upgrade linux-image-generic`, then reboot
- 4. For other distributions: Upgrade to a kernel version >= 5.15.34, >= 5.16.20, >= 5.17.3, or >= 5.19
- 5. After reboot, verify the fix is applied by checking `cat /proc/version` matches the expected fixed version
Generated from the published advisory — verify against the referenced sources before acting.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2022-49090 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2022-49090 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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