CVE-2024-50100
Description
From CVE.org
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.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 5.5 | 5.5 | N/A |
| Attack Vector | Local | Local | N/A |
| Attack Complexity | Low | Low | N/A |
| Privileges Required | Low | Low | N/A |
| User Interaction | None | None | N/A |
| Scope | Unchanged | Unchanged | N/A |
| Confidentiality | None | None | N/A |
| Integrity Impact | None | None | N/A |
| Availability Impact | High | High | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Memory
If the uninitialized pointer is used in a read operation, an attacker might be able to read sensitive portions of memory.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
If the uninitialized pointer references a memory location that is not accessible to the product, or points to a location that is "malformed" (such as NULL) or larger than expected by a read or write operation, then a crash may occur.
Integrity,Confidentiality,Availability
Technical Impact: Execute Unauthorized Code or Commands
If the uninitialized pointer is used in a function call, or points to unexpected data in a write operation, then code execution may be possible.
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