1 files changed, 73 insertions, 86 deletions

diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index 495c395f9def..5d269f583dac 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -1,22 +1,10 @@
+// SPDX-License-Identifier: LGPL-2.1
 /*
  *   fs/cifs/connect.c
  *
  *   Copyright (C) International Business Machines  Corp., 2002,2011
  *   Author(s): Steve French (sfrench@us.ibm.com)
  *
- *   This library is free software; you can redistribute it and/or modify
- *   it under the terms of the GNU Lesser General Public License as published
- *   by the Free Software Foundation; either version 2.1 of the License, or
- *   (at your option) any later version.
- *
- *   This library is distributed in the hope that it will be useful,
- *   but WITHOUT ANY WARRANTY; without even the implied warranty of
- *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
- *   the GNU Lesser General Public License for more details.
- *
- *   You should have received a copy of the GNU Lesser General Public License
- *   along with this library; if not, write to the Free Software
- *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  */
 #include <linux/fs.h>
 #include <linux/net.h>
@@ -368,13 +356,7 @@ cifs_reconnect(struct TCP_Server_Info *server)
 			cifs_server_dbg(VFS, "%s: failed to update DFS target hint: rc = %d\n",
 				 __func__, rc);
 		}
-		rc = dfs_cache_update_vol(cifs_sb->origin_fullpath, server);
-		if (rc) {
-			cifs_server_dbg(VFS, "%s: failed to update vol info in DFS cache: rc = %d\n",
-				 __func__, rc);
-		}
 		dfs_cache_free_tgts(&tgt_list);
-
 	}
 
 	cifs_put_tcp_super(sb);
@@ -1557,29 +1539,25 @@ out:
 /**
  * cifs_free_ipc - helper to release the session IPC tcon
  *
- * Needs to be called everytime a session is destroyed
+ * Needs to be called everytime a session is destroyed.
+ *
+ * On session close, the IPC is closed and the server must release all tcons of the session.
+ * No need to send a tree disconnect here.
+ *
+ * Besides, it will make the server to not close durable and resilient files on session close, as
+ * specified in MS-SMB2 3.3.5.6 Receiving an SMB2 LOGOFF Request.
  */
 static int
 cifs_free_ipc(struct cifs_ses *ses)
 {
-	int rc = 0, xid;
 	struct cifs_tcon *tcon = ses->tcon_ipc;
 
 	if (tcon == NULL)
 		return 0;
 
-	if (ses->server->ops->tree_disconnect) {
-		xid = get_xid();
-		rc = ses->server->ops->tree_disconnect(xid, tcon);
-		free_xid(xid);
-	}
-
-	if (rc)
-		cifs_dbg(FYI, "failed to disconnect IPC tcon (rc=%d)\n", rc);
-
 	tconInfoFree(tcon);
 	ses->tcon_ipc = NULL;
-	return rc;
+	return 0;
 }
 
 static struct cifs_ses *
@@ -1605,7 +1583,6 @@ void cifs_put_smb_ses(struct cifs_ses *ses)
 {
 	unsigned int rc, xid;
 	struct TCP_Server_Info *server = ses->server;
-
 	cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
 
 	spin_lock(&cifs_tcp_ses_lock);
@@ -1613,13 +1590,20 @@ void cifs_put_smb_ses(struct cifs_ses *ses)
 		spin_unlock(&cifs_tcp_ses_lock);
 		return;
 	}
+
+	cifs_dbg(FYI, "%s: ses_count=%d\n", __func__, ses->ses_count);
+	cifs_dbg(FYI, "%s: ses ipc: %s\n", __func__, ses->tcon_ipc ? ses->tcon_ipc->treeName : "NONE");
+
 	if (--ses->ses_count > 0) {
 		spin_unlock(&cifs_tcp_ses_lock);
 		return;
 	}
+	spin_unlock(&cifs_tcp_ses_lock);
+
+	spin_lock(&GlobalMid_Lock);
 	if (ses->status == CifsGood)
 		ses->status = CifsExiting;
-	spin_unlock(&cifs_tcp_ses_lock);
+	spin_unlock(&GlobalMid_Lock);
 
 	cifs_free_ipc(ses);
 
@@ -1951,10 +1935,7 @@ cifs_find_tcon(struct cifs_ses *ses, struct smb3_fs_context *ctx)
 	spin_lock(&cifs_tcp_ses_lock);
 	list_for_each(tmp, &ses->tcon_list) {
 		tcon = list_entry(tmp, struct cifs_tcon, tcon_list);
-#ifdef CONFIG_CIFS_DFS_UPCALL
-		if (tcon->dfs_path)
-			continue;
-#endif
+
 		if (!match_tcon(tcon, ctx))
 			continue;
 		++tcon->tc_count;
@@ -3017,9 +2998,8 @@ expand_dfs_referral(const unsigned int xid, struct cifs_ses *ses,
 	return rc;
 }
 
-static inline int get_next_dfs_tgt(const char *path,
-				   struct dfs_cache_tgt_list *tgt_list,
-				   struct dfs_cache_tgt_iterator **tgt_it)
+static int get_next_dfs_tgt(struct dfs_cache_tgt_list *tgt_list,
+			    struct dfs_cache_tgt_iterator **tgt_it)
 {
 	if (!*tgt_it)
 		*tgt_it = dfs_cache_get_tgt_iterator(tgt_list);
@@ -3059,6 +3039,7 @@ static int do_dfs_failover(const char *path, const char *full_path, struct cifs_
 			   struct cifs_ses **ses, struct cifs_tcon **tcon)
 {
 	int rc;
+	char *npath = NULL;
 	struct dfs_cache_tgt_list tgt_list = {0};
 	struct dfs_cache_tgt_iterator *tgt_it = NULL;
 	struct smb3_fs_context tmp_ctx = {NULL};
@@ -3066,11 +3047,15 @@ static int do_dfs_failover(const char *path, const char *full_path, struct cifs_
 	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_DFS)
 		return -EOPNOTSUPP;
 
-	cifs_dbg(FYI, "%s: path=%s full_path=%s\n", __func__, path, full_path);
+	npath = dfs_cache_canonical_path(path, cifs_sb->local_nls, cifs_remap(cifs_sb));
+	if (IS_ERR(npath))
+		return PTR_ERR(npath);
+
+	cifs_dbg(FYI, "%s: path=%s full_path=%s\n", __func__, npath, full_path);
 
-	rc = dfs_cache_noreq_find(path, NULL, &tgt_list);
+	rc = dfs_cache_noreq_find(npath, NULL, &tgt_list);
 	if (rc)
-		return rc;
+		goto out;
 	/*
 	 * We use a 'tmp_ctx' here because we need pass it down to the mount_{get,put} functions to
 	 * test connection against new DFS targets.
@@ -3084,11 +3069,11 @@ static int do_dfs_failover(const char *path, const char *full_path, struct cifs_
 		char *fake_devname = NULL, *mdata = NULL;
 
 		/* Get next DFS target server - if any */
-		rc = get_next_dfs_tgt(path, &tgt_list, &tgt_it);
+		rc = get_next_dfs_tgt(&tgt_list, &tgt_it);
 		if (rc)
 			break;
 
-		rc = dfs_cache_get_tgt_referral(path, tgt_it, &ref);
+		rc = dfs_cache_get_tgt_referral(npath, tgt_it, &ref);
 		if (rc)
 			break;
 
@@ -3137,6 +3122,7 @@ static int do_dfs_failover(const char *path, const char *full_path, struct cifs_
 	}
 
 out:
+	kfree(npath);
 	smb3_cleanup_fs_context_contents(&tmp_ctx);
 	dfs_cache_free_tgts(&tgt_list);
 	return rc;
@@ -3288,25 +3274,18 @@ static int is_path_remote(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *
 }
 
 #ifdef CONFIG_CIFS_DFS_UPCALL
-static void set_root_ses(struct cifs_sb_info *cifs_sb, struct cifs_ses *ses,
+static void set_root_ses(struct cifs_sb_info *cifs_sb, const uuid_t *mount_id, struct cifs_ses *ses,
 			 struct cifs_ses **root_ses)
 {
 	if (ses) {
 		spin_lock(&cifs_tcp_ses_lock);
 		ses->ses_count++;
-		if (ses->tcon_ipc)
-			ses->tcon_ipc->remap = cifs_remap(cifs_sb);
 		spin_unlock(&cifs_tcp_ses_lock);
+		dfs_cache_add_refsrv_session(mount_id, ses);
 	}
 	*root_ses = ses;
 }
 
-static void put_root_ses(struct cifs_ses *ses)
-{
-	if (ses)
-		cifs_put_smb_ses(ses);
-}
-
 /* Set up next dfs prefix path in @dfs_path */
 static int next_dfs_prepath(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx,
 			    const unsigned int xid, struct TCP_Server_Info *server,
@@ -3352,17 +3331,25 @@ out:
 }
 
 /* Check if resolved targets can handle any DFS referrals */
-static int is_referral_server(const char *ref_path, struct cifs_tcon *tcon, bool *ref_server)
+static int is_referral_server(const char *ref_path, struct cifs_sb_info *cifs_sb,
+			      struct cifs_tcon *tcon, bool *ref_server)
 {
 	int rc;
 	struct dfs_info3_param ref = {0};
 
+	cifs_dbg(FYI, "%s: ref_path=%s\n", __func__, ref_path);
+
 	if (is_tcon_dfs(tcon)) {
 		*ref_server = true;
 	} else {
-		cifs_dbg(FYI, "%s: ref_path=%s\n", __func__, ref_path);
+		char *npath;
 
-		rc = dfs_cache_noreq_find(ref_path, &ref, NULL);
+		npath = dfs_cache_canonical_path(ref_path, cifs_sb->local_nls, cifs_remap(cifs_sb));
+		if (IS_ERR(npath))
+			return PTR_ERR(npath);
+
+		rc = dfs_cache_noreq_find(npath, &ref, NULL);
+		kfree(npath);
 		if (rc) {
 			cifs_dbg(VFS, "%s: dfs_cache_noreq_find: failed (rc=%d)\n", __func__, rc);
 			return rc;
@@ -3386,9 +3373,9 @@ int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
 	struct cifs_ses *ses = NULL, *root_ses = NULL;
 	struct cifs_tcon *tcon = NULL;
 	int count = 0;
+	uuid_t mount_id = {0};
 	char *ref_path = NULL, *full_path = NULL;
 	char *oldmnt = NULL;
-	char *mntdata = NULL;
 	bool ref_server = false;
 
 	rc = mount_get_conns(ctx, cifs_sb, &xid, &server, &ses, &tcon);
@@ -3411,12 +3398,9 @@ int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
 		if (rc != -EREMOTE)
 			goto error;
 	}
-	/* Save mount options */
-	mntdata = kstrdup(cifs_sb->ctx->mount_options, GFP_KERNEL);
-	if (!mntdata) {
-		rc = -ENOMEM;
-		goto error;
-	}
+
+	ctx->nosharesock = true;
+
 	/* Get path of DFS root */
 	ref_path = build_unc_path_to_root(ctx, cifs_sb, false);
 	if (IS_ERR(ref_path)) {
@@ -3425,7 +3409,8 @@ int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
 		goto error;
 	}
 
-	set_root_ses(cifs_sb, ses, &root_ses);
+	uuid_gen(&mount_id);
+	set_root_ses(cifs_sb, &mount_id, ses, &root_ses);
 	do {
 		/* Save full path of last DFS path we used to resolve final target server */
 		kfree(full_path);
@@ -3456,13 +3441,11 @@ int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
 			continue;
 
 		/* Make sure that requests go through new root servers */
-		rc = is_referral_server(ref_path + 1, tcon, &ref_server);
+		rc = is_referral_server(ref_path + 1, cifs_sb, tcon, &ref_server);
 		if (rc)
 			break;
-		if (ref_server) {
-			put_root_ses(root_ses);
-			set_root_ses(cifs_sb, ses, &root_ses);
-		}
+		if (ref_server)
+			set_root_ses(cifs_sb, &mount_id, ses, &root_ses);
 
 		/* Get next dfs path and then continue chasing them if -EREMOTE */
 		rc = next_dfs_prepath(cifs_sb, ctx, xid, server, tcon, &ref_path);
@@ -3471,12 +3454,10 @@ int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
 			rc = -ELOOP;
 	} while (rc == -EREMOTE);
 
-	if (rc)
+	if (rc || !tcon)
 		goto error;
-	put_root_ses(root_ses);
-	root_ses = NULL;
+
 	kfree(ref_path);
-	ref_path = NULL;
 	/*
 	 * Store DFS full path in both superblock and tree connect structures.
 	 *
@@ -3485,21 +3466,27 @@ int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
 	 * links, the prefix path is included in both and may be changed during reconnect.  See
 	 * cifs_tree_connect().
 	 */
-	cifs_sb->origin_fullpath = kstrdup(full_path, GFP_KERNEL);
-	if (!cifs_sb->origin_fullpath) {
+	ref_path = dfs_cache_canonical_path(full_path, cifs_sb->local_nls, cifs_remap(cifs_sb));
+	kfree(full_path);
+	full_path = NULL;
+
+	if (IS_ERR(ref_path)) {
+		rc = PTR_ERR(ref_path);
+		ref_path = NULL;
+		goto error;
+	}
+	cifs_sb->origin_fullpath = ref_path;
+
+	ref_path = kstrdup(cifs_sb->origin_fullpath, GFP_KERNEL);
+	if (!ref_path) {
 		rc = -ENOMEM;
 		goto error;
 	}
 	spin_lock(&cifs_tcp_ses_lock);
-	tcon->dfs_path = full_path;
-	full_path = NULL;
-	tcon->remap = cifs_remap(cifs_sb);
+	tcon->dfs_path = ref_path;
+	ref_path = NULL;
 	spin_unlock(&cifs_tcp_ses_lock);
 
-	/* Add original context for DFS cache to be used when refreshing referrals */
-	rc = dfs_cache_add_vol(mntdata, ctx, cifs_sb->origin_fullpath);
-	if (rc)
-		goto error;
 	/*
 	 * After reconnecting to a different server, unique ids won't
 	 * match anymore, so we disable serverino. This prevents
@@ -3514,6 +3501,7 @@ int cifs_mount(struct cifs_sb_info *cifs_sb, struct smb3_fs_context *ctx)
 	kfree(cifs_sb->prepath);
 	cifs_sb->prepath = ctx->prepath;
 	ctx->prepath = NULL;
+	uuid_copy(&cifs_sb->dfs_mount_id, &mount_id);
 
 out:
 	free_xid(xid);
@@ -3523,9 +3511,8 @@ out:
 error:
 	kfree(ref_path);
 	kfree(full_path);
-	kfree(mntdata);
 	kfree(cifs_sb->origin_fullpath);
-	put_root_ses(root_ses);
+	dfs_cache_put_refsrv_sessions(&mount_id);
 	mount_put_conns(cifs_sb, xid, server, ses, tcon);
 	return rc;
 }
@@ -3755,7 +3742,7 @@ cifs_umount(struct cifs_sb_info *cifs_sb)
 
 	kfree(cifs_sb->prepath);
 #ifdef CONFIG_CIFS_DFS_UPCALL
-	dfs_cache_del_vol(cifs_sb->origin_fullpath);
+	dfs_cache_put_refsrv_sessions(&cifs_sb->dfs_mount_id);
 	kfree(cifs_sb->origin_fullpath);
 #endif
 	call_rcu(&cifs_sb->rcu, delayed_free);