CVE-2022-49450
What it is
In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix listen() setting the bar too high for the prealloc rings AF_RXRPC's listen() handler lets you set the backlog up to 32 (if you bump up the sysctl), but whilst the preallocation circular buffers have 32 slots in them, one of them has to be a dead slot because we're using CIRC_CNT(). This means that listen(rxrpc_sock, 32) will cause an oops when the socket is closed because rxrpc_service_prealloc_one() allocated one too many calls and rxrpc_discard_prealloc() won't then be able to get rid of them because it'll think the ring is empty. rxrpc_release_calls_on_socket() then tries to abort them, but oopses because call->peer isn't yet set. Fix this by setting the maximum backlog to RXRPC_BACKLOG_MAX - 1 to match the ring capacity. BUG: kernel NULL pointer dereference, address: 0000000000000086 ... RIP: 0010:rxrpc_send_abort_packet+0x73/0x240 [rxrpc] Call Trace: <TASK> ? __wake_up_common_lock+0x7a/0x90 ? rxrpc_notify_socket+0x8e/0x140 [rxrpc] ? rxrpc_abort_call+0x4c/0x60 [rxrpc] rxrpc_release_calls_on_socket+0x107/0x1a0 [rxrpc] rxrpc_release+0xc9/0x1c0 [rxrpc] __sock_release+0x37/0xa0 sock_close+0x11/0x20 __fput+0x89/0x240 task_work_run+0x59/0x90 do_exit+0x319/0xaa0
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
- Modified
Affected
- Linux Kernel < 4.9.318
- Linux Kernel < 4.14.283
- Linux Kernel < 4.19.247
- Linux Kernel < 5.4.198
- Linux Kernel < 5.10.121
- Linux Kernel < 5.15.46
- Linux Kernel < 5.17.14
- Linux Kernel < 5.18.3
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-2022-49450.md and follow it. Check whether this project is affected by CVE-2022-49450. 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/369de57492c4f1a42563c5a3bd365822ca3bfc79
- https://git.kernel.org/stable/c/4a3a78b7918bdd723d8c7c9786522ca969bffcc4
- https://git.kernel.org/stable/c/5b4826657d36c218e9f08e8d3223b0edce3de88f
- https://git.kernel.org/stable/c/616f76498d5ddf26b997caf64a95cda3c8a55533
- https://git.kernel.org/stable/c/61fb38cfbb1d54d3dafd0c25752f684b3cd00b32
- https://git.kernel.org/stable/c/88e22159750b0d55793302eeed8ee603f5c1a95c
- https://git.kernel.org/stable/c/91b34bf0409f43bb60453bab23c5beadd726d022
- https://git.kernel.org/stable/c/b3a9b227d5e7467b8518160ff034ea22bb9de573
- https://git.kernel.org/stable/c/e198f1930050e3115c80b67d9249f80f98a27c67
References
- https://git.kernel.org/stable/c/369de57492c4f1a42563c5a3bd365822ca3bfc79
- https://git.kernel.org/stable/c/4a3a78b7918bdd723d8c7c9786522ca969bffcc4
- https://git.kernel.org/stable/c/5b4826657d36c218e9f08e8d3223b0edce3de88f
- https://git.kernel.org/stable/c/616f76498d5ddf26b997caf64a95cda3c8a55533
- https://git.kernel.org/stable/c/61fb38cfbb1d54d3dafd0c25752f684b3cd00b32
- https://git.kernel.org/stable/c/88e22159750b0d55793302eeed8ee603f5c1a95c
- https://git.kernel.org/stable/c/91b34bf0409f43bb60453bab23c5beadd726d022
- https://git.kernel.org/stable/c/b3a9b227d5e7467b8518160ff034ea22bb9de573
- https://git.kernel.org/stable/c/e198f1930050e3115c80b67d9249f80f98a27c67