Package: nfs-common
Version: 2.6.2-4
Severity: important
Tags: patch upstream
On some of our bookworm systems I've seen what looked like a file descriptor
leak. Sample lsof output:
[...]
rpc.idmap 675 root 126r DIR 0,400 10813
/run/rpc_pipefs/nfs/clnt11e6 (deleted)
rpc.idmap 675 root 127u FIFO 0,40 0t0 10817
/run/rpc_pipefs/nfs/clnt11e6/idmap (deleted)
rpc.idmap 675 root 128r DIR 0,400 10834
/run/rpc_pipefs/nfs/clnt11ef (deleted)
rpc.idmap 675 root 129u FIFO 0,40 0t0 10838
/run/rpc_pipefs/nfs/clnt11ef/idmap (deleted)
rpc.idmap 675 root 130r DIR 0,400 10855
/run/rpc_pipefs/nfs/clnt11f8 (deleted)
rpc.idmap 675 root 131u FIFO 0,40 0t0 10859
/run/rpc_pipefs/nfs/clnt11f8/idmap (deleted)
Cranking up the verbosity level to 3 showed that dirscancb never reaps stale
entries in its queue (no "Stale client" lines). The reason turns out to be that
the scan terminates on the first directory entry that doesn't contain an
"idmap" file. Applying the attached patch seems to have solved the problem for
me.
As far as I can tell the bug is still present upstream, and has been for many
years (that "goto out" is from 2007 and replaced a "return" so the bug is even
older than that).
Marking "important" since this has actually caused observable problems in our
environment.From: Sergio Gelato
Date: Tue, 4 Jun 2024 16:02:59 +0200
Subject: rpc.idmapd: nfsopen() failures should not be fatal
dirscancb() loops over all clnt* subdirectories of /run/rpc_pipefs/nfs/.
Some of these directories contain /idmap files, others don't. nfsopen()
returns -1 for the latter; we then want to skip the directory, not abort
the entire scan.
---
utils/idmapd/idmapd.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/utils/idmapd/idmapd.c b/utils/idmapd/idmapd.c
index e79c124..f3c540d 100644
--- a/utils/idmapd/idmapd.c
+++ b/utils/idmapd/idmapd.c
@@ -556,7 +556,7 @@ dirscancb(int fd, short UNUSED(which), void *data)
if (nfsopen(ic) == -1) {
close(ic->ic_dirfd);
free(ic);
-goto out;
+continue;
}
if (verbose > 2)
