| Message ID | 1407591840-19080-1-git-send-email-rosslagerwall@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Sat, Aug 09, 2014 at 02:44:00PM +0100, Ross Lagerwall wrote: > When creating a file that already exists in a read-only directory with > O_EXCL, the NFSv3 server returns EACCES rather than EEXIST (which local > files and the NFSv4 server return). Fix this by checking the MAY_CREATE > permission only if the file does not exist. Since this already happens > in do_nfsd_create, the check in nfsd3_proc_create can simply be removed. Thanks. From a look at the history I believe the server has behaved this way since the beginning. Is this creating a practical problem for you? How did you notice it? Inclined to apply it just for consistency as you suggest. And because it removes some unnecessary code. But as a low priority: for 3.18 and not stable. --b. > > Signed-off-by: Ross Lagerwall <rosslagerwall@gmail.com> > --- > fs/nfsd/nfs3proc.c | 5 ----- > 1 file changed, 5 deletions(-) > > diff --git a/fs/nfsd/nfs3proc.c b/fs/nfsd/nfs3proc.c > index 4012899..8ebd4ac 100644 > --- a/fs/nfsd/nfs3proc.c > +++ b/fs/nfsd/nfs3proc.c > @@ -227,11 +227,6 @@ nfsd3_proc_create(struct svc_rqst *rqstp, struct nfsd3_createargs *argp, > newfhp = fh_init(&resp->fh, NFS3_FHSIZE); > attr = &argp->attrs; > > - /* Get the directory inode */ > - nfserr = fh_verify(rqstp, dirfhp, S_IFDIR, NFSD_MAY_CREATE); > - if (nfserr) > - RETURN_STATUS(nfserr); > - > /* Unfudge the mode bits */ > attr->ia_mode &= ~S_IFMT; > if (!(attr->ia_valid & ATTR_MODE)) { > -- > 2.0.3 > -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, Aug 11, 2014 at 03:08:38PM -0400, J. Bruce Fields wrote: > On Sat, Aug 09, 2014 at 02:44:00PM +0100, Ross Lagerwall wrote: > > When creating a file that already exists in a read-only directory with > > O_EXCL, the NFSv3 server returns EACCES rather than EEXIST (which local > > files and the NFSv4 server return). Fix this by checking the MAY_CREATE > > permission only if the file does not exist. Since this already happens > > in do_nfsd_create, the check in nfsd3_proc_create can simply be removed. > > Thanks. > > From a look at the history I believe the server has behaved this way > since the beginning. Is this creating a practical problem for you? How > did you notice it? I help maintain GNOME's gvfs and so I have a bunch of test programs which I run to check for conformance. I noticed that: gvfs-save /mnt/dir/file fails with a permission denied error when file is on an NFSv3 mount and dir is read-only. Basically, gvfs-save first tries to create the file. If it already exists, then it just truncates it. But on NFSv3, the first creation generates a permission denied error so the operation is aborted. Not really a practical problem, but it is possible to see this with various real-world programs which do a similar dance when saving like this: open(path, O_WRONLY|O_CREAT|O_EXCL) if EEXIST: open(path, O_WRONLY|O_CREAT|O_TRUNC) else: bail() (For Linux NFS clients, the kernel does its own client-side caching so if you do: ls /mnt/dir; gvfs-save /mnt/dir/file it magically works!) > > Inclined to apply it just for consistency as you suggest. And because > it removes some unnecessary code. But as a low priority: for 3.18 and > not stable. > OK, your decision. That is OK with me. Cheers,
diff --git a/fs/nfsd/nfs3proc.c b/fs/nfsd/nfs3proc.c index 4012899..8ebd4ac 100644 --- a/fs/nfsd/nfs3proc.c +++ b/fs/nfsd/nfs3proc.c @@ -227,11 +227,6 @@ nfsd3_proc_create(struct svc_rqst *rqstp, struct nfsd3_createargs *argp, newfhp = fh_init(&resp->fh, NFS3_FHSIZE); attr = &argp->attrs; - /* Get the directory inode */ - nfserr = fh_verify(rqstp, dirfhp, S_IFDIR, NFSD_MAY_CREATE); - if (nfserr) - RETURN_STATUS(nfserr); - /* Unfudge the mode bits */ attr->ia_mode &= ~S_IFMT; if (!(attr->ia_valid & ATTR_MODE)) {
When creating a file that already exists in a read-only directory with O_EXCL, the NFSv3 server returns EACCES rather than EEXIST (which local files and the NFSv4 server return). Fix this by checking the MAY_CREATE permission only if the file does not exist. Since this already happens in do_nfsd_create, the check in nfsd3_proc_create can simply be removed. Signed-off-by: Ross Lagerwall <rosslagerwall@gmail.com> --- fs/nfsd/nfs3proc.c | 5 ----- 1 file changed, 5 deletions(-)