Re: kern/44625: memory exhaustion on NFS server while writing many files

[David Holland <dholland-bugs%netbsd.org@localhost>]

The following reply was made to PR kern/44625; it has been noted by GNATS.

From: David Holland <dholland-bugs%netbsd.org@localhost>
To: gnats-bugs%NetBSD.org@localhost, Mindaugas Rasiukevicius 
<rmind%netbsd.org@localhost>
Cc: 
Subject: Re: kern/44625: memory exhaustion on NFS server while writing many
 files
Date: Thu, 17 Mar 2011 09:18:53 +0000

 On Thu, Mar 17, 2011 at 05:35:01AM +0000, Mindaugas Rasiukevicius wrote:
  >  > The Npage of pnbufpl grows extremely.
  >  > 
  >  > I also tried some kernels checked out on other date. It seems that
  >  > this leakage is seen after struct componentname changes on Nov 30 2010.
  >  
  >  http://nxr.netbsd.org/xref/src/sys/nfs/nfs_serv.c?r=1.156#465
  >  
  >  A leak in this error path (at least)?
 
 good catch and boy don't I feel stupid. :-/
 
 This may help (not tested yet though):
 
 Index: nfs/nfs_serv.c
 ===================================================================
 RCS file: /cvsroot/src/sys/nfs/nfs_serv.c,v
 retrieving revision 1.156
 diff -u -p -r1.156 nfs_serv.c
 --- nfs/nfs_serv.c     5 Feb 2011 13:35:11 -0000       1.156
 +++ nfs/nfs_serv.c     17 Mar 2011 09:14:46 -0000
 @@ -463,6 +463,12 @@ nfsrv_lookup(struct nfsrv_descript *nfsd
        }
  
        if (error) {
 +              if (nd.ni_pathbuf != NULL) {
 +                      pathbuf_destroy(nd.ni_pathbuf);
 +              }
 +              if (ipb != NULL) {
 +                      pathbuf_destroy(ipb);
 +              }
                nfsm_reply(NFSX_POSTOPATTR(v3));
                nfsm_srvpostop_attr(dirattr_ret, &dirattr);
                return (0);
 Index: nfs/nfs_srvsubs.c
 ===================================================================
 RCS file: /cvsroot/src/sys/nfs/nfs_srvsubs.c,v
 retrieving revision 1.8
 diff -u -p -r1.8 nfs_srvsubs.c
 --- nfs/nfs_srvsubs.c  30 Nov 2010 10:30:03 -0000      1.8
 +++ nfs/nfs_srvsubs.c  17 Mar 2011 09:14:46 -0000
 @@ -276,6 +276,7 @@ nfs_namei(struct nameidata *ndp, nfsrvfh
  out:
        if (ndp->ni_pathbuf != NULL) {
                pathbuf_destroy(ndp->ni_pathbuf);
 +              ndp->ni_pathbuf = NULL;
        } else {
                PNBUF_PUT(path);
        }
 
 
 -- 
 David A. Holland
 dholland%netbsd.org@localhost