Merge tag '6.3-rc2-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs client fixes from Steve French:
"Seven cifs/smb3 client fixes, all also for stable:

- four DFS fixes

- multichannel reconnect fix

- fix smb1 stats for cancel command

- fix for set file size error path"

* tag '6.3-rc2-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
cifs: use DFS root session instead of tcon ses
cifs: return DFS root session id in DebugData
cifs: fix use-after-free bug in refresh_cache_worker()
cifs: set DFS root session in cifs_get_smb_ses()
cifs: generate signkey for the channel that's reconnecting
cifs: Fix smb2_set_path_size()
cifs: Move the in_send statistic to __smb_send_rqst()

fs/cifs/cifs_debug.c

···
 				   from_kuid(&init_user_ns, ses->linux_uid),
 				   from_kuid(&init_user_ns, ses->cred_uid));
 
+			if (ses->dfs_root_ses) {
+				seq_printf(m, "\n\tDFS root session id: 0x%llx",
+					   ses->dfs_root_ses->Suid);
+			}
+
 			spin_lock(&ses->chan_lock);
 			if (CIFS_CHAN_NEEDS_RECONNECT(ses, 0))
 				seq_puts(m, "\tPrimary channel: DISCONNECTED ");

fs/cifs/cifs_dfs_ref.c

···
 	tmp.source = full_path;
 	tmp.leaf_fullpath = NULL;
 	tmp.UNC = tmp.prepath = NULL;
+	tmp.dfs_root_ses = NULL;
 
 	rc = smb3_fs_context_dup(ctx, &tmp);
 	if (rc) {

fs/cifs/cifs_fs_sb.h

···
 	/* only used when CIFS_MOUNT_USE_PREFIX_PATH is set */
 	char *prepath;
 
-	/* randomly generated 128-bit number for indexing dfs mount groups in referral cache */
-	uuid_t dfs_mount_id;
 	/*
 	 * Indicate whether serverino option was turned off later
 	 * (cifs_autodisable_serverino) in order to match new mounts.

fs/cifs/cifsglob.h

···
 	/* BB add field for back pointer to sb struct(s)? */
 #ifdef CONFIG_CIFS_DFS_UPCALL
 	struct list_head ulist; /* cache update list */
+	struct list_head dfs_ses_list;
 #endif
 	struct delayed_work	query_interfaces; /* query interfaces workqueue job */
 };
···
 	struct TCP_Server_Info *server;
 	struct cifs_ses *ses;
 	struct cifs_tcon *tcon;
-	struct cifs_ses *root_ses;
-	uuid_t mount_id;
 	char *origin_fullpath, *leaf_fullpath;
+	struct list_head dfs_ses_list;
 };
 
 static inline void free_dfs_info_param(struct dfs_info3_param *param)

fs/cifs/connect.c

···
 	 * need to lock before changing something in the session.
 	 */
 	spin_lock(&cifs_tcp_ses_lock);
+	ses->dfs_root_ses = ctx->dfs_root_ses;
 	list_add(&ses->smb_ses_list, &server->smb_ses_list);
 	spin_unlock(&cifs_tcp_ses_lock);
 
···
 	bool isdfs;
 	int rc;
 
-	uuid_gen(&mnt_ctx.mount_id);
+	INIT_LIST_HEAD(&mnt_ctx.dfs_ses_list);
+
 	rc = dfs_mount_share(&mnt_ctx, &isdfs);
 	if (rc)
 		goto error;
···
 	kfree(cifs_sb->prepath);
 	cifs_sb->prepath = ctx->prepath;
 	ctx->prepath = NULL;
-	uuid_copy(&cifs_sb->dfs_mount_id, &mnt_ctx.mount_id);
 
 out:
 	cifs_try_adding_channels(cifs_sb, mnt_ctx.ses);
···
 	return rc;
 
 error:
-	dfs_cache_put_refsrv_sessions(&mnt_ctx.mount_id);
+	dfs_put_root_smb_sessions(&mnt_ctx.dfs_ses_list);
 	kfree(mnt_ctx.origin_fullpath);
 	kfree(mnt_ctx.leaf_fullpath);
 	cifs_mount_put_conns(&mnt_ctx);
···
 	spin_unlock(&cifs_sb->tlink_tree_lock);
 
 	kfree(cifs_sb->prepath);
-#ifdef CONFIG_CIFS_DFS_UPCALL
-	dfs_cache_put_refsrv_sessions(&cifs_sb->dfs_mount_id);
-#endif
 	call_rcu(&cifs_sb->rcu, delayed_free);
 }
 

fs/cifs/dfs.c

···
 	ctx->leaf_fullpath = (char *)full_path;
 	rc = cifs_mount_get_session(mnt_ctx);
 	ctx->leaf_fullpath = NULL;
-	if (!rc) {
-		struct cifs_ses *ses = mnt_ctx->ses;
 
-		mutex_lock(&ses->session_mutex);
-		ses->dfs_root_ses = mnt_ctx->root_ses;
-		mutex_unlock(&ses->session_mutex);
-	}
 	return rc;
 }
 
-static void set_root_ses(struct cifs_mount_ctx *mnt_ctx)
+static int get_root_smb_session(struct cifs_mount_ctx *mnt_ctx)
 {
-	if (mnt_ctx->ses) {
+	struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
+	struct dfs_root_ses *root_ses;
+	struct cifs_ses *ses = mnt_ctx->ses;
+
+	if (ses) {
+		root_ses = kmalloc(sizeof(*root_ses), GFP_KERNEL);
+		if (!root_ses)
+			return -ENOMEM;
+
+		INIT_LIST_HEAD(&root_ses->list);
+
 		spin_lock(&cifs_tcp_ses_lock);
-		mnt_ctx->ses->ses_count++;
+		ses->ses_count++;
 		spin_unlock(&cifs_tcp_ses_lock);
-		dfs_cache_add_refsrv_session(&mnt_ctx->mount_id, mnt_ctx->ses);
+		root_ses->ses = ses;
+		list_add_tail(&root_ses->list, &mnt_ctx->dfs_ses_list);
 	}
-	mnt_ctx->root_ses = mnt_ctx->ses;
+	ctx->dfs_root_ses = ses;
+	return 0;
 }
 
 static int get_dfs_conn(struct cifs_mount_ctx *mnt_ctx, const char *ref_path, const char *full_path,
···
 {
 	struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
 	struct dfs_info3_param ref = {};
-	int rc;
+	bool is_refsrv = false;
+	int rc, rc2;
 
 	rc = dfs_cache_get_tgt_referral(ref_path + 1, tit, &ref);
 	if (rc)
···
 	if (rc)
 		goto out;
 
-	if (ref.flags & DFSREF_REFERRAL_SERVER)
-		set_root_ses(mnt_ctx);
+	is_refsrv = !!(ref.flags & DFSREF_REFERRAL_SERVER);
 
 	rc = -EREMOTE;
 	if (ref.flags & DFSREF_STORAGE_SERVER) {
···
 			goto out;
 
 		/* some servers may not advertise referral capability under ref.flags */
-		if (!(ref.flags & DFSREF_REFERRAL_SERVER) &&
-		    is_tcon_dfs(mnt_ctx->tcon))
-			set_root_ses(mnt_ctx);
+		is_refsrv |= is_tcon_dfs(mnt_ctx->tcon);
 
 		rc = cifs_is_path_remote(mnt_ctx);
+	}
+
+	if (rc == -EREMOTE && is_refsrv) {
+		rc2 = get_root_smb_session(mnt_ctx);
+		if (rc2)
+			rc = rc2;
 	}
 
 out:
···
 	char *ref_path = NULL, *full_path = NULL;
 	struct dfs_cache_tgt_iterator *tit;
 	struct TCP_Server_Info *server;
+	struct cifs_tcon *tcon;
 	char *origin_fullpath = NULL;
 	int num_links = 0;
 	int rc;
···
 
 	if (!rc) {
 		server = mnt_ctx->server;
+		tcon = mnt_ctx->tcon;
 
 		mutex_lock(&server->refpath_lock);
-		server->origin_fullpath = origin_fullpath;
-		server->current_fullpath = server->leaf_fullpath;
+		if (!server->origin_fullpath) {
+			server->origin_fullpath = origin_fullpath;
+			server->current_fullpath = server->leaf_fullpath;
+			origin_fullpath = NULL;
+		}
 		mutex_unlock(&server->refpath_lock);
-		origin_fullpath = NULL;
+
+		if (list_empty(&tcon->dfs_ses_list)) {
+			list_replace_init(&mnt_ctx->dfs_ses_list,
+					  &tcon->dfs_ses_list);
+		} else {
+			dfs_put_root_smb_sessions(&mnt_ctx->dfs_ses_list);
+		}
 	}
 
 out:
···
 	rc = get_session(mnt_ctx, NULL);
 	if (rc)
 		return rc;
-	mnt_ctx->root_ses = mnt_ctx->ses;
+	ctx->dfs_root_ses = mnt_ctx->ses;
 	/*
 	 * If called with 'nodfs' mount option, then skip DFS resolving.  Otherwise unconditionally
 	 * try to get an DFS referral (even cached) to determine whether it is an DFS mount.
···
 	}
 
 	*isdfs = true;
-	set_root_ses(mnt_ctx);
+	rc = get_root_smb_session(mnt_ctx);
+	if (rc)
+		return rc;
 
 	return __dfs_mount_share(mnt_ctx);
 }

fs/cifs/dfs.h

···
 #include "fs_context.h"
 #include "cifs_unicode.h"
 
+struct dfs_root_ses {
+	struct list_head list;
+	struct cifs_ses *ses;
+};
+
 int dfs_parse_target_referral(const char *full_path, const struct dfs_info3_param *ref,
 			      struct smb3_fs_context *ctx);
 int dfs_mount_share(struct cifs_mount_ctx *mnt_ctx, bool *isdfs);
···
 static inline int dfs_get_referral(struct cifs_mount_ctx *mnt_ctx, const char *path,
 				   struct dfs_info3_param *ref, struct dfs_cache_tgt_list *tl)
 {
+	struct smb3_fs_context *ctx = mnt_ctx->fs_ctx;
 	struct cifs_sb_info *cifs_sb = mnt_ctx->cifs_sb;
 
-	return dfs_cache_find(mnt_ctx->xid, mnt_ctx->root_ses, cifs_sb->local_nls,
+	return dfs_cache_find(mnt_ctx->xid, ctx->dfs_root_ses, cifs_sb->local_nls,
 			      cifs_remap(cifs_sb), path, ref, tl);
 }
 
···
 							server->origin_fullpath,
 							strlen(server->origin_fullpath),
 							true);
+}
+
+static inline void dfs_put_root_smb_sessions(struct list_head *head)
+{
+	struct dfs_root_ses *root, *tmp;
+
+	list_for_each_entry_safe(root, tmp, head, list) {
+		list_del_init(&root->list);
+		cifs_put_smb_ses(root->ses);
+		kfree(root);
+	}
 }
 
 #endif /* _CIFS_DFS_H */

fs/cifs/dfs_cache.c

···
 	struct cache_dfs_tgt *tgthint;
 };
 
-/* List of referral server sessions per dfs mount */
-struct mount_group {
-	struct list_head list;
-	uuid_t id;
-	struct cifs_ses *sessions[CACHE_MAX_ENTRIES];
-	int num_sessions;
-	spinlock_t lock;
-	struct list_head refresh_list;
-	struct kref refcount;
-};
-
 static struct kmem_cache *cache_slab __read_mostly;
 static struct workqueue_struct *dfscache_wq __read_mostly;
 
···
 static struct hlist_head cache_htable[CACHE_HTABLE_SIZE];
 static DECLARE_RWSEM(htable_rw_lock);
 
-static LIST_HEAD(mount_group_list);
-static DEFINE_MUTEX(mount_group_list_lock);
-
 static void refresh_cache_worker(struct work_struct *work);
 
 static DECLARE_DELAYED_WORK(refresh_task, refresh_cache_worker);
-
-static void __mount_group_release(struct mount_group *mg)
-{
-	int i;
-
-	for (i = 0; i < mg->num_sessions; i++)
-		cifs_put_smb_ses(mg->sessions[i]);
-	kfree(mg);
-}
-
-static void mount_group_release(struct kref *kref)
-{
-	struct mount_group *mg = container_of(kref, struct mount_group, refcount);
-
-	mutex_lock(&mount_group_list_lock);
-	list_del(&mg->list);
-	mutex_unlock(&mount_group_list_lock);
-	__mount_group_release(mg);
-}
-
-static struct mount_group *find_mount_group_locked(const uuid_t *id)
-{
-	struct mount_group *mg;
-
-	list_for_each_entry(mg, &mount_group_list, list) {
-		if (uuid_equal(&mg->id, id))
-			return mg;
-	}
-	return ERR_PTR(-ENOENT);
-}
-
-static struct mount_group *__get_mount_group_locked(const uuid_t *id)
-{
-	struct mount_group *mg;
-
-	mg = find_mount_group_locked(id);
-	if (!IS_ERR(mg))
-		return mg;
-
-	mg = kmalloc(sizeof(*mg), GFP_KERNEL);
-	if (!mg)
-		return ERR_PTR(-ENOMEM);
-	kref_init(&mg->refcount);
-	uuid_copy(&mg->id, id);
-	mg->num_sessions = 0;
-	spin_lock_init(&mg->lock);
-	list_add(&mg->list, &mount_group_list);
-	return mg;
-}
-
-static struct mount_group *get_mount_group(const uuid_t *id)
-{
-	struct mount_group *mg;
-
-	mutex_lock(&mount_group_list_lock);
-	mg = __get_mount_group_locked(id);
-	if (!IS_ERR(mg))
-		kref_get(&mg->refcount);
-	mutex_unlock(&mount_group_list_lock);
-
-	return mg;
-}
-
-static void free_mount_group_list(void)
-{
-	struct mount_group *mg, *tmp_mg;
-
-	list_for_each_entry_safe(mg, tmp_mg, &mount_group_list, list) {
-		list_del_init(&mg->list);
-		__mount_group_release(mg);
-	}
-}
 
 /**
  * dfs_cache_canonical_path - get a canonical DFS path
···
 {
 	cancel_delayed_work_sync(&refresh_task);
 	unload_nls(cache_cp);
-	free_mount_group_list();
 	flush_cache_ents();
 	kmem_cache_destroy(cache_slab);
 	destroy_workqueue(dfscache_wq);
···
 	return rc;
 }
 
-/**
- * dfs_cache_add_refsrv_session - add SMB session of referral server
- *
- * @mount_id: mount group uuid to lookup.
- * @ses: reference counted SMB session of referral server.
- */
-void dfs_cache_add_refsrv_session(const uuid_t *mount_id, struct cifs_ses *ses)
-{
-	struct mount_group *mg;
-
-	if (WARN_ON_ONCE(!mount_id || uuid_is_null(mount_id) || !ses))
-		return;
-
-	mg = get_mount_group(mount_id);
-	if (WARN_ON_ONCE(IS_ERR(mg)))
-		return;
-
-	spin_lock(&mg->lock);
-	if (mg->num_sessions < ARRAY_SIZE(mg->sessions))
-		mg->sessions[mg->num_sessions++] = ses;
-	spin_unlock(&mg->lock);
-	kref_put(&mg->refcount, mount_group_release);
-}
-
-/**
- * dfs_cache_put_refsrv_sessions - put all referral server sessions
- *
- * Put all SMB sessions from the given mount group id.
- *
- * @mount_id: mount group uuid to lookup.
- */
-void dfs_cache_put_refsrv_sessions(const uuid_t *mount_id)
-{
-	struct mount_group *mg;
-
-	if (!mount_id || uuid_is_null(mount_id))
-		return;
-
-	mutex_lock(&mount_group_list_lock);
-	mg = find_mount_group_locked(mount_id);
-	if (IS_ERR(mg)) {
-		mutex_unlock(&mount_group_list_lock);
-		return;
-	}
-	mutex_unlock(&mount_group_list_lock);
-	kref_put(&mg->refcount, mount_group_release);
-}
-
 /* Extract share from DFS target and return a pointer to prefix path or NULL */
 static const char *parse_target_share(const char *target, char **share)
 {
···
 	if (!server->origin_fullpath) {
 		cifs_dbg(FYI, "%s: not a dfs mount\n", __func__);
 		return 0;
-	}
-
-	if (uuid_is_null(&cifs_sb->dfs_mount_id)) {
-		cifs_dbg(FYI, "%s: no dfs mount group id\n", __func__);
-		return -EINVAL;
 	}
 	/*
 	 * After reconnecting to a different server, unique ids won't match anymore, so we disable

fs/cifs/dfs_cache.h

···
 			       struct dfs_info3_param *ref);
 int dfs_cache_get_tgt_share(char *path, const struct dfs_cache_tgt_iterator *it, char **share,
 			    char **prefix);
-void dfs_cache_put_refsrv_sessions(const uuid_t *mount_id);
-void dfs_cache_add_refsrv_session(const uuid_t *mount_id, struct cifs_ses *ses);
 char *dfs_cache_canonical_path(const char *path, const struct nls_table *cp, int remap);
 int dfs_cache_remount_fs(struct cifs_sb_info *cifs_sb);
 

fs/cifs/fs_context.h

···
 	bool rootfs:1; /* if it's a SMB root file system */
 	bool witness:1; /* use witness protocol */
 	char *leaf_fullpath;
+	struct cifs_ses *dfs_root_ses;
 };
 
 extern const struct fs_parameter_spec smb3_fs_parameters[];

fs/cifs/misc.c

···
 #ifdef CONFIG_CIFS_DFS_UPCALL
 #include "dns_resolve.h"
 #include "dfs_cache.h"
+#include "dfs.h"
 #endif
 #include "fs_context.h"
 #include "cached_dir.h"
···
 	spin_lock_init(&ret_buf->stat_lock);
 	atomic_set(&ret_buf->num_local_opens, 0);
 	atomic_set(&ret_buf->num_remote_opens, 0);
+#ifdef CONFIG_CIFS_DFS_UPCALL
+	INIT_LIST_HEAD(&ret_buf->dfs_ses_list);
+#endif
 
 	return ret_buf;
 }
···
 	atomic_dec(&tconInfoAllocCount);
 	kfree(tcon->nativeFileSystem);
 	kfree_sensitive(tcon->password);
+#ifdef CONFIG_CIFS_DFS_UPCALL
+	dfs_put_root_smb_sessions(&tcon->dfs_ses_list);
+#endif
 	kfree(tcon);
 }
 
···
 		 * removing cached DFS targets that the client would eventually
 		 * need during failover.
 		 */
+		ses = CIFS_DFS_ROOT_SES(ses);
 		if (ses->server->ops->get_dfs_refer &&
 		    !ses->server->ops->get_dfs_refer(xid, ses, ref_path, &refs,
 						     &num_refs, cifs_sb->local_nls,

fs/cifs/smb2inode.c

···
 		size[0] = 8; /* sizeof __le64 */
 		data[0] = ptr;
 
-		rc = SMB2_set_info_init(tcon, server,
-					&rqst[num_rqst], COMPOUND_FID,
-					COMPOUND_FID, current->tgid,
-					FILE_END_OF_FILE_INFORMATION,
-					SMB2_O_INFO_FILE, 0, data, size);
+		if (cfile) {
+			rc = SMB2_set_info_init(tcon, server,
+						&rqst[num_rqst],
+						cfile->fid.persistent_fid,
+						cfile->fid.volatile_fid,
+						current->tgid,
+						FILE_END_OF_FILE_INFORMATION,
+						SMB2_O_INFO_FILE, 0,
+						data, size);
+		} else {
+			rc = SMB2_set_info_init(tcon, server,
+						&rqst[num_rqst],
+						COMPOUND_FID,
+						COMPOUND_FID,
+						current->tgid,
+						FILE_END_OF_FILE_INFORMATION,
+						SMB2_O_INFO_FILE, 0,
+						data, size);
+			if (!rc) {
+				smb2_set_next_command(tcon, &rqst[num_rqst]);
+				smb2_set_related(&rqst[num_rqst]);
+			}
+		}
 		if (rc)
 			goto finished;
-		smb2_set_next_command(tcon, &rqst[num_rqst]);
-		smb2_set_related(&rqst[num_rqst++]);
+		num_rqst++;
 		trace_smb3_set_eof_enter(xid, ses->Suid, tcon->tid, full_path);
 		break;
 	case SMB2_OP_SET_INFO:

fs/cifs/smb2transport.c

···
 
 		/* safe to access primary channel, since it will never go away */
 		spin_lock(&ses->chan_lock);
-		memcpy(ses->chans[0].signkey, ses->smb3signingkey,
+		memcpy(ses->chans[chan_index].signkey, ses->smb3signingkey,
 		       SMB3_SIGN_KEY_SIZE);
 		spin_unlock(&ses->chan_lock);
 

fs/cifs/transport.c

···
 __smb_send_rqst(struct TCP_Server_Info *server, int num_rqst,
 		struct smb_rqst *rqst)
 {
-	int rc = 0;
+	int rc;
 	struct kvec *iov;
 	int n_vec;
 	unsigned int send_length = 0;
···
 	struct msghdr smb_msg = {};
 	__be32 rfc1002_marker;
 
+	cifs_in_send_inc(server);
 	if (cifs_rdma_enabled(server)) {
 		/* return -EAGAIN when connecting or reconnecting */
 		rc = -EAGAIN;
···
 		goto smbd_done;
 	}
 
+	rc = -EAGAIN;
 	if (ssocket == NULL)
-		return -EAGAIN;
+		goto out;
 
+	rc = -ERESTARTSYS;
 	if (fatal_signal_pending(current)) {
 		cifs_dbg(FYI, "signal pending before send request\n");
-		return -ERESTARTSYS;
+		goto out;
 	}
 
+	rc = 0;
 	/* cork the socket */
 	tcp_sock_set_cork(ssocket->sk, true);
 
···
 			 rc);
 	else if (rc > 0)
 		rc = 0;
-
+out:
+	cifs_in_send_dec(server);
 	return rc;
 }
 
···
 	 * I/O response may come back and free the mid entry on another thread.
 	 */
 	cifs_save_when_sent(mid);
-	cifs_in_send_inc(server);
 	rc = smb_send_rqst(server, 1, rqst, flags);
-	cifs_in_send_dec(server);
 
 	if (rc < 0) {
 		revert_current_mid(server, mid->credits);
···
 		else
 			midQ[i]->callback = cifs_compound_last_callback;
 	}
-	cifs_in_send_inc(server);
 	rc = smb_send_rqst(server, num_rqst, rqst, flags);
-	cifs_in_send_dec(server);
 
 	for (i = 0; i < num_rqst; i++)
 		cifs_save_when_sent(midQ[i]);
···
 
 	midQ->mid_state = MID_REQUEST_SUBMITTED;
 
-	cifs_in_send_inc(server);
 	rc = smb_send(server, in_buf, len);
-	cifs_in_send_dec(server);
 	cifs_save_when_sent(midQ);
 
 	if (rc < 0)
···
 	}
 
 	midQ->mid_state = MID_REQUEST_SUBMITTED;
-	cifs_in_send_inc(server);
 	rc = smb_send(server, in_buf, len);
-	cifs_in_send_dec(server);
 	cifs_save_when_sent(midQ);
 
 	if (rc < 0)