From: Hu Weiwen sehuww@mail.scut.edu.cn
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@mail.scut.edu.cn Reviewed-by: Xiubo Li xiubli@redhat.com Signed-off-by: Ilya Dryomov idryomov@gmail.com [Xiubo: fixed a trivial conflict for 5.10 backport] Signed-off-by: Xiubo Li xiubli@redhat.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/ceph/file.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)
--- a/fs/ceph/file.c +++ b/fs/ceph/file.c @@ -381,6 +381,12 @@ int ceph_atomic_open(struct inode *dir, if (dentry->d_name.len > NAME_MAX) return -ENAMETOOLONG;
+ /* + * 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); if (err < 0) @@ -411,9 +417,7 @@ int ceph_atomic_open(struct inode *dir,
req->r_parent = dir; set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags); - 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;