CVE-2024-50100

Nov. 12, 2024, 2:57 p.m.

5.5
Medium

Description

In the Linux kernel, the following vulnerability has been resolved: USB: gadget: dummy-hcd: Fix "task hung" problem The syzbot fuzzer has been encountering "task hung" problems ever since the dummy-hcd driver was changed to use hrtimers instead of regular timers. It turns out that the problems are caused by a subtle difference between the timer_pending() and hrtimer_active() APIs. The changeover blindly replaced the first by the second. However, timer_pending() returns True when the timer is queued but not when its callback is running, whereas hrtimer_active() returns True when the hrtimer is queued _or_ its callback is running. This difference occasionally caused dummy_urb_enqueue() to think that the callback routine had not yet started when in fact it was almost finished. As a result the hrtimer was not restarted, which made it impossible for the driver to dequeue later the URB that was just enqueued. This caused usb_kill_urb() to hang, and things got worse from there. Since hrtimers have no API for telling when they are queued and the callback isn't running, the driver must keep track of this for itself. That's what this patch does, adding a new "timer_pending" flag and setting or clearing it at the appropriate times.

Product(s) Impacted

Vendor Product Versions
Linux
  • Linux Kernel
  • *, 6.12

Weaknesses

Common security weaknesses mapped to this vulnerability.

*CPE(s)

Affected systems and software identified for this CVE.

Type Vendor Product Version Update Edition Language Software Edition Target Software Target Hardware Other Information
o linux linux_kernel / / / / / / / /
o linux linux_kernel 6.12 rc1 / / / / / /
o linux linux_kernel 6.12 rc2 / / / / / /
o linux linux_kernel 6.12 rc3 / / / / / /

CVSS Score

5.5 / 10

CVSS Data

  • Attack Vector: LOCAL
  • Attack Complexity: LOW
  • Privileges Required: LOW
  • Scope: UNCHANGED
  • Confidentiality Impact: NONE
  • Integrity Impact: NONE
  • Availability Impact: HIGH
  • View Vector String

    CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Date

  • Published: Nov. 5, 2024, 6:15 p.m.
  • Last Modified: Nov. 12, 2024, 2:57 p.m.

Status : Analyzed

CVE has been recently published to the CVE List and has been received by the NVD.

More info

Source

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

*Disclaimer: Some vulnerabilities do not have an associated CPE. To enhance the data, we use AI to infer CPEs based on CVE details. This is an automated process and might not always be accurate.