cifs: Add support for mounting Windows 2008 DFS shares (c1508ca2) · Commits · e / devices / android_kernel_sony_msm8994

Windows 2008 CIFS servers do not always return PATH_NOT_COVERED when attempting to access a DFS share. Therefore, when checking for remote shares, unconditionally ask for a DFS referral for the UNC (w/out prepath) before continuing with previous behavior of attempting to access the UNC + prepath and checking for PATH_NOT_COVERED. Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=31092 Reviewed-by:

Jeff Layton <jlayton@redhat.com> Signed-off-by:

Sean Finney <seanius@seanius.net> Signed-off-by:

Pavel Shilovsky <piastry@etersoft.ru> Signed-off-by:

Steve French <sfrench@us.ibm.com>

fs/cifs/connect.c

+18 −0

Original line number	Diff line number	Diff line
		@@ -2937,6 +2937,24 @@ try_mount_again:
		(tcon->ses->server->maxBuf - MAX_CIFS_HDR_SIZE));

		remote_path_check:
		#ifdef CONFIG_CIFS_DFS_UPCALL
		/*
		* Perform an unconditional check for whether there are DFS
		* referrals for this path without prefix, to provide support
		* for DFS referrals from w2k8 servers which don't seem to respond
		* with PATH_NOT_COVERED to requests that include the prefix.
		* Chase the referral if found, otherwise continue normally.
		*/
		if (referral_walks_count == 0) {
		int refrc = expand_dfs_referral(xid, pSesInfo, volume_info,
		cifs_sb, &mount_data, false);
		if (!refrc) {
		referral_walks_count++;
		goto try_mount_again;
		}
		}
		#endif

		/* check if a whole path (including prepath) is not remote */
		if (!rc && tcon) {
		/* build_path_to_root works only when we have a valid tcon */