CVE-2023-53045
What it is
In the Linux kernel, the following vulnerability has been resolved: usb: gadget: u_audio: don't let userspace block driver unbind In the unbind callback for f_uac1 and f_uac2, a call to snd_card_free() via g_audio_cleanup() will disconnect the card and then wait for all resources to be released, which happens when the refcount falls to zero. Since userspace can keep the refcount incremented by not closing the relevant file descriptor, the call to unbind may block indefinitely. This can cause a deadlock during reboot, as evidenced by the following blocked task observed on my machine: task:reboot state:D stack:0 pid:2827 ppid:569 flags:0x0000000c Call trace: __switch_to+0xc8/0x140 __schedule+0x2f0/0x7c0 schedule+0x60/0xd0 schedule_timeout+0x180/0x1d4 wait_for_completion+0x78/0x180 snd_card_free+0x90/0xa0 g_audio_cleanup+0x2c/0x64 afunc_unbind+0x28/0x60 ... kernel_restart+0x4c/0xac __do_sys_reboot+0xcc/0x1ec __arm64_sys_reboot+0x28/0x30 invoke_syscall+0x4c/0x110 ... The issue can also be observed by opening the card with arecord and then stopping the process through the shell before unbinding: # arecord -D hw:UAC2Gadget -f S32_LE -c 2 -r 48000 /dev/null Recording WAVE '/dev/null' : Signed 32 bit Little Endian, Rate 48000 Hz, Stereo ^Z[1]+ Stopped arecord -D hw:UAC2Gadget -f S32_LE -c 2 -r 48000 /dev/null # echo gadget.0 > /sys/bus/gadget/drivers/configfs-gadget/unbind (observe that the unbind command never finishes) Fix the problem by using snd_card_free_when_closed() instead, which will still disconnect the card as desired, but defer the task of freeing the resources to the core once userspace closes its file descriptor.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of service disruption.
- Exploit odds
- 0.2% 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: 0.2% in the next 30 days (EPSS).
- Severity: 5.5 MEDIUM (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.2% · EPSS, next 30 days
- Weakness
- CWE-667
- Record status
- Analyzed
Affected
- Linux Kernel < 4.14.312
- Linux Kernel < 4.19.280
- Linux Kernel < 5.4.240
- Linux Kernel < 5.10.177
- Linux Kernel < 5.15.105
- Linux Kernel < 6.1.22
- Linux Kernel < 6.2.9
- Linux Kernel 6.3
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-2023-53045.md and follow it. Check whether this project is affected by CVE-2023-53045. 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/0eda2004f38d95ef5715d62be884cd344260535b
- https://git.kernel.org/stable/c/3256e152b645fc1e788ba44c2d8ced690113e3e6
- https://git.kernel.org/stable/c/33f341c1fc60e172a3515c51bdabee11e83d1ee9
- https://git.kernel.org/stable/c/3bc7324e4911351e39c54a62e6ca46321cb10faf
- https://git.kernel.org/stable/c/3e016ef2e72da93a2ea7afbb45de1b481b44d761
- https://git.kernel.org/stable/c/43ca70753dfffd517d2af126da28690f8f615605
- https://git.kernel.org/stable/c/6c67ed9ad9b83e453e808f9b31a931a20a25629b
- https://git.kernel.org/stable/c/b131989797f7287d7fdadb2bababc05a15d44750
References
- https://git.kernel.org/stable/c/0eda2004f38d95ef5715d62be884cd344260535b
- https://git.kernel.org/stable/c/3256e152b645fc1e788ba44c2d8ced690113e3e6
- https://git.kernel.org/stable/c/33f341c1fc60e172a3515c51bdabee11e83d1ee9
- https://git.kernel.org/stable/c/3bc7324e4911351e39c54a62e6ca46321cb10faf
- https://git.kernel.org/stable/c/3e016ef2e72da93a2ea7afbb45de1b481b44d761
- https://git.kernel.org/stable/c/43ca70753dfffd517d2af126da28690f8f615605
- https://git.kernel.org/stable/c/6c67ed9ad9b83e453e808f9b31a931a20a25629b
- https://git.kernel.org/stable/c/b131989797f7287d7fdadb2bababc05a15d44750