summaryrefslogtreecommitdiffstats
path: root/fs/cifs
diff options
context:
space:
mode:
authorSachin Prabhu <sprabhu@redhat.com>2017-04-16 20:37:24 +0100
committerSteve French <smfrench@gmail.com>2017-04-17 15:44:23 -0500
commit62a6cfddcc0a5313e7da3e8311ba16226fe0ac10 (patch)
tree3f1ce0ef2db15fb6bbdd8a426cfe50d185beb122 /fs/cifs
parent4f7d029b9bf009fbee76bb10c0c4351a1870d2f3 (diff)
downloadlinux-62a6cfddcc0a5313e7da3e8311ba16226fe0ac10.tar.bz2
cifs: Do not send echoes before Negotiate is complete
commit 4fcd1813e640 ("Fix reconnect to not defer smb3 session reconnect long after socket reconnect") added support for Negotiate requests to be initiated by echo calls. To avoid delays in calling echo after a reconnect, I added the patch introduced by the commit b8c600120fc8 ("Call echo service immediately after socket reconnect"). This has however caused a regression with cifs shares which do not have support for echo calls to trigger Negotiate requests. On connections which need to call Negotiation, the echo calls trigger an error which triggers a reconnect which in turn triggers another echo call. This results in a loop which is only broken when an operation is performed on the cifs share. For an idle share, it can DOS a server. The patch uses the smb_operation can_echo() for cifs so that it is called only if connection has been already been setup. kernel bz: 194531 Signed-off-by: Sachin Prabhu <sprabhu@redhat.com> Tested-by: Jonathan Liu <net147@gmail.com> Acked-by: Pavel Shilovsky <pshilov@microsoft.com> CC: Stable <stable@vger.kernel.org> Signed-off-by: Steve French <smfrench@gmail.com>
Diffstat (limited to 'fs/cifs')
-rw-r--r--fs/cifs/smb1ops.c10
1 files changed, 10 insertions, 0 deletions
diff --git a/fs/cifs/smb1ops.c b/fs/cifs/smb1ops.c
index cc93ba4da9b5..27bc360c7ffd 100644
--- a/fs/cifs/smb1ops.c
+++ b/fs/cifs/smb1ops.c
@@ -1015,6 +1015,15 @@ cifs_dir_needs_close(struct cifsFileInfo *cfile)
return !cfile->srch_inf.endOfSearch && !cfile->invalidHandle;
}
+static bool
+cifs_can_echo(struct TCP_Server_Info *server)
+{
+ if (server->tcpStatus == CifsGood)
+ return true;
+
+ return false;
+}
+
struct smb_version_operations smb1_operations = {
.send_cancel = send_nt_cancel,
.compare_fids = cifs_compare_fids,
@@ -1049,6 +1058,7 @@ struct smb_version_operations smb1_operations = {
.get_dfs_refer = CIFSGetDFSRefer,
.qfs_tcon = cifs_qfs_tcon,
.is_path_accessible = cifs_is_path_accessible,
+ .can_echo = cifs_can_echo,
.query_path_info = cifs_query_path_info,
.query_file_info = cifs_query_file_info,
.get_srv_inum = cifs_get_srv_inum,