Pull procfs fixes from Christian Brauner:
"Mode changes to files under /proc/<pid>/ aren't supported ever since
commit
6d76fa58b050 ("Don't allow chmod() on the /proc/<pid>/ files").
Due to an oversight in commit
1b3044e39a89 ("procfs: fix pthread
cross-thread naming if !PR_DUMPABLE") in switching from REG to NOD,
mode changes on /proc/thread-self/comm were accidently allowed.
Similar, mode changes for all files beneath /proc/<pid>/net/ are
blocked but mode changes on /proc/<pid>/net itself were accidently
allowed.
Both issues come down to not using the generic proc_setattr() helper
which blocks all mode changes. This is rectified with this pull
request.
This also removes a strange nolibc test that abused /proc/<pid>/net
for testing mode changes. Using procfs for this test never made a lot
of sense given procfs has special semantics for almost everything
anway.
Both changes are minor user-visible changes. It is however very
unlikely that mode changes on proc/<pid>/net and
/proc/thread-self/comm are something that userspace relies on"
* tag 'v6.6-fs.proc.uapi' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
procfs: block chmod on /proc/thread-self/comm
proc: use generic setattr() for /proc/$PID/net
selftests/nolibc: drop test chmod_net