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> --- 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 da59e836a06e..a5ecb97b6f41 100644 --- a/fs/ceph/file.c +++ b/fs/ceph/file.c @@ -757,6 +757,11 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry, /* If it's not being looked up, it's negative */ return -ENOENT; } + /* + * 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: /* do the open */ req = prepare_open_request(dir->i_sb, flags, mode); @@ -807,9 +812,7 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry, } 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); if (err == -ENOENT) { dentry = ceph_handle_snapdir(req, dentry); if (IS_ERR(dentry)) { -- 2.25.1