CVE-2025-40305

unknown
Published โ€” ยท Modified โ€”
CVSS v3
โ€”
CVSS v4 NEW
โ€”
not yet in upstream
VIR risk
โ€”

Description

In the Linux kernel, the following vulnerability has been resolved: 9p/trans_fd: p9_fd_request: kick rx thread if EPOLLIN p9_read_work() doesn't set Rworksched and doesn't do schedule_work(m->rq) if list_empty(&m->req_list). However, if the pipe is full, we need to read more data and this used to work prior to commit aaec5a95d59615 ("pipe_read: don't wake up the writer if the pipe is still full"). p9_read_work() does p9_fd_read() -> ... -> anon_pipe_read() which (before the commit above) triggered the unnecessary wakeup. This wakeup calls p9_pollwake() which kicks p9_poll_workfn() -> p9_poll_mux(), p9_poll_mux() will notice EPOLLIN and schedule_work(&m->rq). This no longer happens after the optimization above, change p9_fd_request() to use p9_poll_mux() instead of only checking for EPOLLOUT.

Predictions

Exploit likelihood
20%
Patch ETA
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Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

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OS impact

OSVersionStatusFixed in
suse slesaffected
debian debianbookwormfixed0
debian debianbullseyefixed0
debian debianforkyfixed6.17.8-1
debian debiansidfixed6.17.8-1
debian debiantrixiefixed0

References

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.