2.6.35-longterm review patch. If anyone has any objections, please let me know.
------------------ From: Sachin Prabhu <[email protected]> commit 1574dff8996ab1ed92c09012f8038b5566fce313 upstream. An open on a NFS4 share using the O_CREAT flag on an existing file for which we have permissions to open but contained in a directory with no write permissions will fail with EACCES. A tcpdump shows that the client had set the open mode to UNCHECKED which indicates that the file should be created if it doesn't exist and encountering an existing flag is not an error. Since in this case the file exists and can be opened by the user, the NFS server is wrong in attempting to check create permissions on the parent directory. The patch adds a conditional statement to check for create permissions only if the file doesn't exist. Signed-off-by: Sachin S. Prabhu <[email protected]> Signed-off-by: J. Bruce Fields <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> Signed-off-by: Andi Kleen <[email protected]> --- fs/nfsd/vfs.c | 9 ++++++++- 1 file changed, 8 insertions(+), 1 deletion(-) Index: linux-2.6.35.y/fs/nfsd/vfs.c =================================================================== --- linux-2.6.35.y.orig/fs/nfsd/vfs.c +++ linux-2.6.35.y/fs/nfsd/vfs.c @@ -1386,7 +1386,7 @@ nfsd_create_v3(struct svc_rqst *rqstp, s goto out; if (!(iap->ia_valid & ATTR_MODE)) iap->ia_mode = 0; - err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE); + err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_EXEC); if (err) goto out; @@ -1408,6 +1408,13 @@ nfsd_create_v3(struct svc_rqst *rqstp, s if (IS_ERR(dchild)) goto out_nfserr; + /* If file doesn't exist, check for permissions to create one */ + if (!dchild->d_inode) { + err = fh_verify(rqstp, fhp, S_IFDIR, NFSD_MAY_CREATE); + if (err) + goto out; + } + err = fh_compose(resfhp, fhp->fh_export, dchild, fhp); if (err) goto out; _______________________________________________ stable mailing list [email protected] http://linux.kernel.org/mailman/listinfo/stable
