From: Hu Weiwen <sehuww@xxxxxxxxxxxxxxxx>
commit 7cb9994754f8a36ae9e5ec4597c5c4c2d6c03832 upstream.
Clear O_TRUNC from the flags sent in the MDS create request.
`atomic_open' is called before permission check. We should not do any
modification to the file here. The caller will do the truncation
afterward.
Fixes: 124e68e74099 ("ceph: file operations")
Signed-off-by: Hu Weiwen <sehuww@xxxxxxxxxxxxxxxx>
Reviewed-by: Xiubo Li <xiubli@xxxxxxxxxx>
Signed-off-by: Ilya Dryomov <idryomov@xxxxxxxxx>
[Xiubo: fixed a trivial conflict for 4.9 backport]
Signed-off-by: Xiubo Li <xiubli@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/ceph/file.c | 9 ++++++---
1 file changed, 6 insertions(+), 3 deletions(-)
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -354,6 +354,11 @@ int ceph_atomic_open(struct inode *dir,
err = ceph_init_dentry(dentry);
if (err < 0)
return err;
+ /*
+ * Do not truncate the file, since atomic_open is called before the
+ * permission check. The caller will do the truncation afterward.
+ */
+ flags &= ~O_TRUNC;
if (flags & O_CREAT) {
err = ceph_pre_init_acls(dir, &mode, &acls);
@@ -384,9 +389,7 @@ int ceph_atomic_open(struct inode *dir,
req->r_args.open.mask = cpu_to_le32(mask);
req->r_locked_dir = dir; /* caller holds dir->i_mutex */
- err = ceph_mdsc_do_request(mdsc,
- (flags & (O_CREAT|O_TRUNC)) ? dir : NULL,
- req);
+ err = ceph_mdsc_do_request(mdsc, (flags & O_CREAT) ? dir : NULL, req);
err = ceph_handle_snapdir(req, dentry, err);
if (err)
goto out_req;
