CVE-2022-49655

In the Linux kernel, the following vulnerability has been resolved:<br /> <br /> fscache: Fix invalidation/lookup race<br /> <br /> If an NFS file is opened for writing and closed, fscache_invalidate() will<br /> be asked to invalidate the file - however, if the cookie is in the<br /> LOOKING_UP state (or the CREATING state), then request to invalidate<br /> doesn&amp;#39;t get recorded for fscache_cookie_state_machine() to do something<br /> with.<br /> <br /> Fix this by making __fscache_invalidate() set a flag if it sees the cookie<br /> is in the LOOKING_UP state to indicate that we need to go to invalidation.<br /> Note that this requires a count on the n_accesses counter for the state<br /> machine, which that will release when it&amp;#39;s done.<br /> <br /> fscache_cookie_state_machine() then shifts to the INVALIDATING state if it<br /> sees the flag.<br /> <br /> Without this, an nfs file can get corrupted if it gets modified locally and<br /> then read locally as the cache contents may not get updated.