CVE-2023-52895

In the Linux kernel, the following vulnerability has been resolved:

io_uring/poll: don't reissue in case of poll race on multishot request

A previous commit fixed a poll race that can occur, but it's only applicable for multishot requests. For a multishot request, we can safely ignore a spurious wakeup, as we never leave the waitqueue to begin with.

A blunt reissue of a multishot armed request can cause us to leak a buffer, if they are ring provided. While this seems like a bug in itself, it's not really defined behavior to reissue a multishot request directly. It's less efficient to do so as well, and not required to rearm anything like it is for singleshot poll requests.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.