lkml.org 
[lkml]   [2013]   [Mar]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] nfsd: fix bad offset use
On Fri, Mar 22, 2013 at 04:53:53PM -0400, J. Bruce Fields wrote:
> On Fri, Mar 22, 2013 at 11:18:24AM -0700, Kent Overstreet wrote:
> > vfs_writev() updates the offset argument - but the code then passes the
> > offset to vfs_fsync_range(). Since offset now points to the offset after
> > what was just written, this is probably not what was intended
>
> Whoops--thanks! Looks like this was introduced by my
> face15025ffdf664de95e86ae831544154d26c9c "nfsd: use vfs_fsync_range(),
> not O_SYNC, for stable writes", in 3.8.
>
> I'll queue up for 3.9 and stable.

(By the way, out of curiosity: how did you stumble across this?)

--b.

>
> --b.
>
> >
> > Signed-off-by: Kent Overstreet <koverstreet@google.com>
> > Cc: "J. Bruce Fields" <bfields@fieldses.org>
> > Cc: Al Viro <viro@zeniv.linux.org.uk>
> > Cc: "Eric W. Biederman" <ebiederm@xmission.com>
> > Cc: Zach Brown <zab@redhat.com>
> > ---
> > fs/nfsd/vfs.c | 3 ++-
> > 1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c
> > index 2a7eb53..2b2e239 100644
> > --- a/fs/nfsd/vfs.c
> > +++ b/fs/nfsd/vfs.c
> > @@ -1013,6 +1013,7 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
> > int host_err;
> > int stable = *stablep;
> > int use_wgather;
> > + loff_t pos = offset;
> >
> > dentry = file->f_path.dentry;
> > inode = dentry->d_inode;
> > @@ -1025,7 +1026,7 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file,
> >
> > /* Write the data. */
> > oldfs = get_fs(); set_fs(KERNEL_DS);
> > - host_err = vfs_writev(file, (struct iovec __user *)vec, vlen, &offset);
> > + host_err = vfs_writev(file, (struct iovec __user *)vec, vlen, &pos);
> > set_fs(oldfs);
> > if (host_err < 0)
> > goto out_nfserr;
> > --
> > 1.8.1.3
> >


\
 
 \ /
  Last update: 2013-03-22 22:42    [W:2.246 / U:0.008 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site