From cc0c473f895a540ad3b3df422dcd01c47df3b731 Mon Sep 17 00:00:00 2001 From: "J. Bruce Fields" Date: Mon, 24 Feb 2014 14:59:47 -0500 Subject: nfsd: notify_change needs elevated write count commit 9f67f189939eccaa54f3d2c9cf10788abaf2d584 upstream. Looks like this bug has been here since these write counts were introduced, not sure why it was just noticed now. Thanks also to Jan Kara for pointing out the problem. Reported-by: Matthew Rahtz Signed-off-by: J. Bruce Fields Signed-off-by: Greg Kroah-Hartman --- fs/nfsd/vfs.c | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'fs') diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 6d7be3f8035..eea5ad18898 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -404,6 +404,7 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap, umode_t ftype = 0; __be32 err; int host_err; + bool get_write_count; int size_change = 0; if (iap->ia_valid & (ATTR_ATIME | ATTR_MTIME | ATTR_SIZE)) @@ -411,10 +412,18 @@ nfsd_setattr(struct svc_rqst *rqstp, struct svc_fh *fhp, struct iattr *iap, if (iap->ia_valid & ATTR_SIZE) ftype = S_IFREG; + /* Callers that do fh_verify should do the fh_want_write: */ + get_write_count = !fhp->fh_dentry; + /* Get inode */ err = fh_verify(rqstp, fhp, ftype, accmode); if (err) goto out; + if (get_write_count) { + host_err = fh_want_write(fhp); + if (host_err) + return nfserrno(host_err); + } dentry = fhp->fh_dentry; inode = dentry->d_inode; -- cgit v1.2.3