Description: vfs: check fd has read access in kernel_read_file_from_fd()
References:
 https://bugzilla.redhat.com/show_bug.cgi?id=2026491
 https://lore.kernel.org/all/20211007220110.600005-1-willy@infradead.org/
 https://lkml.org/lkml/2021/10/6/254
Notes:
 carnil> CVE got rejected by its assigning CNA (Red Hat) because further
 carnil> investigation showed that it was not a security issue. Cf.
 carnil> https://www.cve.org/CVERecord?id=CVE-2022-0644
Bugs:
upstream: released (5.15-rc7) [032146cda85566abcd1c4884d9d23e4e30a07e9a]
5.10-upstream-stable: released (5.10.76) [b721500c979b71a9f02eb84ca384082722c62d4e]
4.19-upstream-stable: released (4.19.214) [c1ba20965b59c2eeb54a845ca5cab4fc7bcf9735]
4.9-upstream-stable: released (4.9.288) [52ed5a196b1146e0368e95edc23c38fa1b50825a]
sid: released (5.14.16-1)
5.10-bullseye-security: released (5.10.84-1)
4.19-buster-security: released (4.19.232-1)
4.9-stretch-security: released (4.9.290-1)