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> --- rebased onto ceph_client repo testing branch fs/ceph/file.c | 9 ++++++--- 1 file changed, 6 insertions(+), 3 deletions(-) diff --git a/fs/ceph/file.c b/fs/ceph/file.c index 296fd1c7ece8..289e66e9cbb0 100644 --- a/fs/ceph/file.c +++ b/fs/ceph/file.c @@ -745,6 +745,11 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry, err = ceph_wait_on_conflict_unlink(dentry); if (err) 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; retry: if (flags & O_CREAT) { @@ -836,9 +841,7 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry, set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags); req->r_new_inode = new_inode; new_inode = NULL; - 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); if (err == -ENOENT) { dentry = ceph_handle_snapdir(req, dentry); if (IS_ERR(dentry)) { -- 2.25.1