by Kastro
Paper/Archive/CVE-2022-48985

CVE-2022-48985

Linux Linux — net: mana: Fix race on per-CQ variable napi work_done

EPSS 0.6%CVSS 9.8
critical.is priorityof 100
39
CVSS 9.8 (CNA)9.8 / 10 × 3029.4Not in CISA KEV+300.0EPSS percentile 48.2.482 × 209.6No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

In the Linux kernel, the following vulnerability has been resolved: net: mana: Fix race on per-CQ variable napi work_done After calling napi_complete_done(), the NAPIF_STATE_SCHED bit may be cleared, and another CPU can start napi thread and access per-CQ variable, cq->work_done. If the other thread (for example, from busy_poll) sets it to a value >= budget, this thread will continue to run when it should stop, and cause memory corruption and panic. To fix this issue, save the per-CQ work_done variable in a local variable before napi_complete_done(), so it won't be corrupted by a possible concurrent thread after napi_complete_done(). Also, add a flag bit to advertise to the NIC firmware: the NAPI work_done variable race is fixed, so the driver is able to reliably support features like busy_poll.

Affected

ProductAffectedFixed inSource
Linuxe1b5683ff62e7b328317aec08869495992053e9d – < fe50a9bbeb1f042e756c5cfa7708112c944368defe50a9bbeb1f042e756c5cfa7708112c944368deCNA
Linuxe1b5683ff62e7b328317aec08869495992053e9d – < 6740d8572ccd1bca50d8a1ca2bedc333f50ed5f36740d8572ccd1bca50d8a1ca2bedc333f50ed5f3CNA
Linuxe1b5683ff62e7b328317aec08869495992053e9d – < 18010ff776fa42340efc428b3ea6d19b3e7c7b2118010ff776fa42340efc428b3ea6d19b3e7c7b21CNA
Linux5.155.15.83CNA

Scores by source

Linux (CNA)9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA ADPSSVCExploitation: none · Automatable: no · Technical impact: partial

References

refgit.kernel.org/stable/c/fe50a9bbeb1f042e756c5cfa7708112c944368derefgit.kernel.org/stable/c/6740d8572ccd1bca50d8a1ca2bedc333f50ed5f3refgit.kernel.org/stable/c/18010ff776fa42340efc428b3ea6d19b3e7c7b21