UBUNTU-CVE-2024-35793
In the Linux kernel, the following vulnerability has been resolved: debugfs: fix wait/cancellation handling during remove Ben Greear further reports deadlocks during concurrent debugfs remove while files are being accessed, even though the code in question now uses debugfs cancellations. Turns out that despite all the review on the locking, we missed completely that the logic is wrong: if the refcount hits zero we can finish (and need not wait for the completion), but if it doesn't we have to trigger all the cancellations. As written, we can _never_ get into the loop triggering the cancellations. Fix this, and explain it better while at it.
02 / AFFECTED SOFTWARE
Affected packages
6 explicit affected versions
4 explicit affected versions
3 explicit affected versions
7 explicit affected versions
35 explicit affected versions
18 explicit affected versions
5 explicit affected versions
13 explicit affected versions
4 explicit affected versions
23 explicit affected versions
7 explicit affected versions
21 explicit affected versions
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10 explicit affected versions
5 explicit affected versions
7 explicit affected versions
12 explicit affected versions
12 explicit affected versions
1 explicit affected versions
7 explicit affected versions
12 explicit affected versions
12 explicit affected versions
37 explicit affected versions
10 explicit affected versions
26 explicit affected versions
13 explicit affected versions
29 explicit affected versions
13 explicit affected versions
33 explicit affected versions
23 explicit affected versions
10 explicit affected versions
12 explicit affected versions
7 explicit affected versions
12 explicit affected versions
10 explicit affected versions
26 explicit affected versions
6 explicit affected versions
6 explicit affected versions
13 explicit affected versions
5 explicit affected versions
16 explicit affected versions
6 explicit affected versions
3 explicit affected versions
51 explicit affected versions
3 explicit affected versions
12 explicit affected versions
27 explicit affected versions
8 explicit affected versions
5 explicit affected versions
8 explicit affected versions
10 explicit affected versions
2 explicit affected versions
13 explicit affected versions
7 explicit affected versions
10 explicit affected versions
12 explicit affected versions
44 explicit affected versions
16 explicit affected versions
3 explicit affected versions
13 explicit affected versions
26 explicit affected versions
37 explicit affected versions
6 explicit affected versions
38 explicit affected versions
9 explicit affected versions
11 explicit affected versions
7 explicit affected versions
4 explicit affected versions
43 explicit affected versions
10 explicit affected versions
8 explicit affected versions
1 explicit affected versions
14 explicit affected versions
4 explicit affected versions
1 explicit affected versions
50 explicit affected versions
6 explicit affected versions
12 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
In the Linux kernel, the following vulnerability has been resolved: debugfs: fix wait/cancellation handling during remove Ben Greear further reports deadlocks during concurrent debugfs remove while files are being accessed, even though the code in question now uses debugfs cancellations. Turns out that despite all the review on the locking, we missed completely that the logic is wrong: if the refcount hits zero we can finish (and need not wait for the completion), but if it doesn't we have to trigger all the cancellations. As written, we can _never_ get into the loop triggering the cancellations. Fix this, and explain it better while at it.
05 / REFERENCES
Further evidence
- https://git.kernel.org/linus/952c3fce297f12c7ff59380adb66b564e2bc9b64
- https://git.kernel.org/stable/c/3d08cca5fd0aabb62b7015067ab40913b33da906
- https://git.kernel.org/stable/c/952c3fce297f12c7ff59380adb66b564e2bc9b64
- https://git.kernel.org/stable/c/e88b5ae01901c4a655a53158397746334778a57b
- https://ubuntu.com/security/CVE-2024-35793
- https://ubuntu.com/security/notices/USN-6816-1
- https://ubuntu.com/security/notices/USN-6817-1
- https://ubuntu.com/security/notices/USN-6817-2
- https://ubuntu.com/security/notices/USN-6817-3
- https://ubuntu.com/security/notices/USN-6878-1
- https://www.cve.org/CVERecord?id=CVE-2024-35793