CVE-2022-49195
What it is
In the Linux kernel, the following vulnerability has been resolved: net: dsa: fix panic on shutdown if multi-chip tree failed to probe DSA probing is atypical because a tree of devices must probe all at once, so out of N switches which call dsa_tree_setup_routing_table() during probe, for (N - 1) of them, "complete" will return false and they will exit probing early. The Nth switch will set up the whole tree on their behalf. The implication is that for (N - 1) switches, the driver binds to the device successfully, without doing anything. When the driver is bound, the ->shutdown() method may run. But if the Nth switch has failed to initialize the tree, there is nothing to do for the (N - 1) driver instances, since the slave devices have not been created, etc. Moreover, dsa_switch_shutdown() expects that the calling @ds has been in fact initialized, so it jumps at dereferencing the various data structures, which is incorrect. Avoid the ensuing NULL pointer dereferences by simply checking whether the Nth switch has previously set "ds->setup = true" for the switch which is currently shutting down. The entire setup is serialized under dsa2_mutex which we already hold.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of service disruption.
- Exploit odds
- 0.3% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.3% in the next 30 days (EPSS).
- Severity: 5.5 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.3% · EPSS, next 30 days
- Weakness
- CWE-476 · NULL pointer dereference
- Record status
- Analyzed
Affected
- Linux Kernel < 5.15.33
- Linux Kernel < 5.16.19
- Linux Kernel < 5.17.2
- Linux Kernel 5.15
Attack profile CVSS 3.1 · 5.5
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2022-49195.md and follow it. Check whether this project is affected by CVE-2022-49195. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/8fd36358ce82382519b50b05f437493e1e00c4a9
- https://git.kernel.org/stable/c/95df5cd5a446df6738d2d45872e08594819080e4
- https://git.kernel.org/stable/c/b6e668ff43ebd87ccc8a19e5481345c428672295
- https://git.kernel.org/stable/c/b864d5350c18bea9369d0bdd9e7eb6f6172cc283