nfsd: don't fail unchecked creates of non-special files
Allow a v3 unchecked open of a non-regular file succeed as if it were a
lookup; typically a client in such a case will want to fall back on a
local open, so succeeding and giving it the filehandle is more useful
than failing with nfserr_exist, which makes it appear that nothing at
all exists by that name.
Similarly for v4, on an open-create, return the same errors we would on
an attempt to open a non-regular file, instead of returning
nfserr_exist.
This fixes a problem found doing a v4 open of a symlink with
O_RDONLY|O_CREAT, which resulted in the current client returning EEXIST.
Thanks also to Trond for analysis.
Cc: stable@kernel.org
Reported-by: Orion Poplawski <orion@cora.nwra.com>
Tested-by: Orion Poplawski <orion@cora.nwra.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/nfs4proc.c b/fs/nfsd/nfs4proc.c
index 2ed14df..8256efd 100644
--- a/fs/nfsd/nfs4proc.c
+++ b/fs/nfsd/nfs4proc.c
@@ -235,17 +235,17 @@
*/
if (open->op_createmode == NFS4_CREATE_EXCLUSIVE && status == 0)
open->op_bmval[1] = (FATTR4_WORD1_TIME_ACCESS |
- FATTR4_WORD1_TIME_MODIFY);
+ FATTR4_WORD1_TIME_MODIFY);
} else {
status = nfsd_lookup(rqstp, current_fh,
open->op_fname.data, open->op_fname.len, resfh);
fh_unlock(current_fh);
- if (status)
- goto out;
- status = nfsd_check_obj_isreg(resfh);
}
if (status)
goto out;
+ status = nfsd_check_obj_isreg(resfh);
+ if (status)
+ goto out;
if (is_create_with_attrs(open) && open->op_acl != NULL)
do_set_nfs4_acl(rqstp, resfh, open->op_acl, open->op_bmval);