From 502aa0a5be633e6558574ebcf63b65afdfbfcd7a Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Wed, 10 Aug 2016 14:46:27 -0400 Subject: [PATCH] nfsd: fix dentry refcounting on create b44061d0b9 introduced a dentry ref counting bug. Previously we were grabbing one ref to dchild in nfsd_create(), but with the creation of nfsd_create_locked() we have a ref for dchild from the lookup in nfsd_create(), and then another ref in nfsd_create_locked(). The ref from the lookup in nfsd_create() is never dropped and results in dentries still in use at unmount. Signed-off-by: Josef Bacik Fixes: b44061d0b9 "nfsd: reorganize nfsd_create" Reported-by: kernel test robot Reviewed-by: Jeff Layton Acked-by: Al Viro Signed-off-by: J. Bruce Fields --- fs/nfsd/vfs.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index ba944123167b..ff476e654b8f 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -1252,10 +1252,13 @@ nfsd_create(struct svc_rqst *rqstp, struct svc_fh *fhp, if (IS_ERR(dchild)) return nfserrno(host_err); err = fh_compose(resfhp, fhp->fh_export, dchild, fhp); - if (err) { - dput(dchild); + /* + * We unconditionally drop our ref to dchild as fh_compose will have + * already grabbed its own ref for it. + */ + dput(dchild); + if (err) return err; - } return nfsd_create_locked(rqstp, fhp, fname, flen, iap, type, rdev, resfhp); }