diff options
| author |   J. Bruce Fields <bfields@citi.umich.edu> | 2006-06-30 01:56:14 -0700 |
|---|---|---|
| committer |   Linus Torvalds <torvalds@g5.osdl.org> | 2006-06-30 11:25:40 -0700 |
| commit | 7fc90ec93a5eb71f4b08403baf5ba7176b3ec6b1 (patch) | |
| tree | 4fc33145b741f153a49d3623b77de82251b7316a /fs | |
| parent | [PATCH] knfsd: nfsd4: fix open_confirm locking (diff) | |
| download | linux-dev-7fc90ec93a5eb71f4b08403baf5ba7176b3ec6b1.tar.xz linux-dev-7fc90ec93a5eb71f4b08403baf5ba7176b3ec6b1.zip | |
[PATCH] knfsd: nfsd: call nfsd_setuser() on fh_compose(), fix nfsd4 permissions problem
In the typical v2/v3 case the only new filehandles used as arguments to
operations are filehandles taken directly off the wire, which don't get
dentries until fh_verify() is called.
But in v4 the filehandles that are arguments to operations were often created
by previous operations (putrootfh, lookup, etc.) using fh_compose, which sets
the dentry in the filehandle without calling nfsd_setuser().
This also means that, for example, if filesystem B is mounted on filesystem A,
and filesystem A is exported without root-squashing, then a client can bypass
the rootsquashing on B using a compound that starts at a filehandle in A,
crosses into B using lookups, and then does stuff in B.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/nfsd/nfsfh.c | 15 |
1 files changed, 8 insertions, 7 deletions
diff --git a/fs/nfsd/nfsfh.c b/fs/nfsd/nfsfh.c index ca96ede30a10..ecc439d2565f 100644 --- a/fs/nfsd/nfsfh.c +++ b/fs/nfsd/nfsfh.c @@ -187,13 +187,6 @@ fh_verify(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, int access) goto out; } - /* Set user creds for this exportpoint */ - error = nfsd_setuser(rqstp, exp); - if (error) { - error = nfserrno(error); - goto out; - } - /* * Look up the dentry using the NFS file handle. */ @@ -251,6 +244,14 @@ fh_verify(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, int access) } cache_get(&exp->h); + /* Set user creds for this exportpoint; necessary even in the "just + * checking" case because this may be a filehandle that was created by + * fh_compose, and that is about to be used in another nfsv4 compound + * operation */ + error = nfserrno(nfsd_setuser(rqstp, exp)); + if (error) + goto out; + error = nfsd_mode_check(rqstp, dentry->d_inode->i_mode, type); if (error) goto out; |