From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jun Piao , Eric Van Hensbergen , Ron Minnich , Latchesar Ionkov , Andrew Morton , Dominique Martinet Subject: [PATCH 4.18 051/145] fs/9p/xattr.c: catch the error of p9_client_clunk when setting xattr failed Date: Fri, 7 Sep 2018 23:08:37 +0200 Message-Id: <20180907210908.765426516@linuxfoundation.org> In-Reply-To: <20180907210903.617721278@linuxfoundation.org> References: <20180907210903.617721278@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: piaojun commit 3111784bee81591ea2815011688d28b65df03627 upstream. In my testing, v9fs_fid_xattr_set will return successfully even if the backend ext4 filesystem has no space to store xattr key-value. That will cause inconsistent behavior between front end and back end. The reason is that lsetxattr will be triggered by p9_client_clunk, and unfortunately we did not catch the error. This patch will catch the error to notify upper caller. p9_client_clunk (in 9p) p9_client_rpc(clnt, P9_TCLUNK, "d", fid->fid); v9fs_clunk (in qemu) put_fid free_fid v9fs_xattr_fid_clunk v9fs_co_lsetxattr s->ops->lsetxattr ext4_xattr_user_set (in host ext4 filesystem) Link: http://lkml.kernel.org/r/5B57EACC.2060900@huawei.com Signed-off-by: Jun Piao Cc: Eric Van Hensbergen Cc: Ron Minnich Cc: Latchesar Ionkov Cc: Andrew Morton Cc: stable@vger.kernel.org Signed-off-by: Dominique Martinet Signed-off-by: Greg Kroah-Hartman --- fs/9p/xattr.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- a/fs/9p/xattr.c +++ b/fs/9p/xattr.c @@ -105,7 +105,7 @@ int v9fs_fid_xattr_set(struct p9_fid *fi { struct kvec kvec = {.iov_base = (void *)value, .iov_len = value_len}; struct iov_iter from; - int retval; + int retval, err; iov_iter_kvec(&from, WRITE | ITER_KVEC, &kvec, 1, value_len); @@ -126,7 +126,9 @@ int v9fs_fid_xattr_set(struct p9_fid *fi retval); else p9_client_write(fid, 0, &from, &retval); - p9_client_clunk(fid); + err = p9_client_clunk(fid); + if (!retval && err) + retval = err; return retval; }