[LTP] [PATCH 2/2] nfsstat01: Check that RPC stats don't leak between net namespaces

[Petr Vorel]

Hi all,

> On Fri, Aug 30, 2024 at 04:13:40PM +0200, Martin Doucha wrote:
> > When the NFS server and client run on the same host in different net
> > namespaces, check that RPC calls from the client namespace don't
> > change RPC statistics in the root namespace.

> > Signed-off-by: Martin Doucha <mdoucha@suse.cz>
> > ---

> > I've initially tried to test both NFS and RPC client stats but it appears
> > that NFS client stats are still shared across all namespaces. Only RPC
> > client stats are separate for each net namespace. The kernel patchset[1]
> > which introduced per-NS stats confirms that only RPC stats have been changed.

Yes, only RPC client stats needed to be fixed in LTP test.

Kind regards,
Petr

> I believe that is correct, Josef changed only RPC counters. Which
> counters did you expect also would be containerized, exactly?
> Perhaps this issue should be raised on linux-nfs@vger, it could be
> considered to be another information leak.


> > If NFS client stats should be separate for each namespace as well, let
> > me know and I'll return the second set of NS checks in patch v2.

> > Tested on kernel v5.14 with Neil's backports.

> > [1] https://lore.kernel.org/linux-nfs/cover.1708026931.git.josef@toxicpanda.com/

> >  testcases/network/nfs/nfsstat01/nfsstat01.sh | 18 ++++++++++++++++--
> >  1 file changed, 16 insertions(+), 2 deletions(-)

> > diff --git a/testcases/network/nfs/nfsstat01/nfsstat01.sh b/testcases/network/nfs/nfsstat01/nfsstat01.sh
> > index 8d7202cf3..3379c4d46 100755
> > --- a/testcases/network/nfs/nfsstat01/nfsstat01.sh
> > +++ b/testcases/network/nfs/nfsstat01/nfsstat01.sh
> > @@ -22,6 +22,7 @@ get_calls()
> >  	local name=$1
> >  	local field=$2
> >  	local nfs_f=$3
> > +	local netns=${4:-rhost}
> >  	local type="lhost"
> >  	local calls opt

> > @@ -30,7 +31,8 @@ get_calls()

> >  	if tst_net_use_netns; then
> >  		# In netns setup, rhost is the client
> > -		[ "$nfs_f" = "nfs" ] && [ $NS_STAT_RHOST -ne 0 ] && type="rhost"
> > +		[ "$nfs_f" = "nfs" ] && [ $NS_STAT_RHOST -ne 0 ] && \
> > +			type="$netns"
> >  	else
> >  		[ "$nfs_f" != "nfs" ] && type="rhost"
> >  	fi
> > @@ -64,13 +66,14 @@ get_calls()
> >  do_test()
> >  {
> >  	local client_calls server_calls new_server_calls new_client_calls
> > -	local client_field server_field
> > +	local client_field server_field root_calls new_root_calls
> >  	local client_v=$VERSION server_v=$VERSION

> >  	tst_res TINFO "checking RPC calls for server/client"

> >  	server_calls="$(get_calls rpc 2 nfsd)"
> >  	client_calls="$(get_calls rpc 2 nfs)"
> > +	root_calls="$(get_calls rpc 2 nfs lhost)"

> >  	tst_res TINFO "calls $server_calls/$client_calls"

> > @@ -79,6 +82,7 @@ do_test()

> >  	new_server_calls="$(get_calls rpc 2 nfsd)"
> >  	new_client_calls="$(get_calls rpc 2 nfs)"
> > +	new_root_calls="$(get_calls rpc 2 nfs lhost)"
> >  	tst_res TINFO "new calls $new_server_calls/$new_client_calls"

> >  	if [ "$new_server_calls" -le "$server_calls" ]; then
> > @@ -93,6 +97,16 @@ do_test()
> >  		tst_res TPASS "client RPC calls increased"
> >  	fi

> > +	if [ $NS_STAT_RHOST -ne 0 ]; then
> > +		tst_res TINFO "Root NS client RPC calls: $root_calls => $new_root_calls"
> > +
> > +		if [ $root_calls -ne $new_root_calls ]; then
> > +			tst_res TFAIL "RPC stats leaked between net namespaces"
> > +		else
> > +			tst_res TPASS "RPC stats stay within net namespaces"
> > +		fi
> > +	fi
> > +
> >  	tst_res TINFO "checking NFS calls for server/client"
> >  	case $VERSION in
> >  	2) client_field=13 server_field=13
> > -- 
> > 2.46.0