On Tue, 2022-12-13 at 11:01 -0500, Jeff Layton wrote: > JianHong reported some strange behavior with automounts on an nfs server > without an explicit pseudoroot. When clients issued a readdir in the > pseudoroot, automounted directories that were not yet mounted would show > up even if they weren't exported, though the clients wouldn't be able to > do anything with them. > > The issue was that triggering the automount on a directory would cause > the mountd upcall to time out, which would cause nfsd to include the > automounted dentry in the readdir response. Eventually, the automount > would work and report that it wasn't exported and subsequent attempts to > access the dentry would (properly) fail. > > We never want mountd to trigger an automount. The kernel should do that > if it wants to use it. Change the junction checks to do an O_PATH open > and use fstatat with AT_NO_AUTOMOUNT. > > Cc: Chuck Lever <chuck.lever@xxxxxxxxxx> > Link: https://bugzilla.redhat.com/show_bug.cgi?id=2148353 > Reported-by: JianHong Yin <jiyin@xxxxxxxxxx> > Signed-off-by: Jeff Layton <jlayton@xxxxxxxxxx> > --- > support/junction/junction.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > Ping? Steve, can you comment on (or merge) this patch? Thanks, -- Jeff Layton <jlayton@xxxxxxxxxx>
