Merge branch 'for-next' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs fixes from Steve French:
 "This ncludes various cifs/smb3 bug fixes, mostly for stable as well.

  In the next week I expect that Germano will have some reconnection
  fixes, and also I expect to have the remaining pieces of the snapshot
  enablement and SMB3 ACLs, but wanted to get this set of bug fixes in"

* 'for-next' of git://git.samba.org/sfrench/cifs-2.6:
  cifs_get_root shouldn't use path with tree name
  Fix default behaviour for empty domains and add domainauto option
  cifs: use %16phN for formatting md5 sum
  cifs: Fix smbencrypt() to stop pointing a scatterlist at the stack
  CIFS: Fix a possible double locking of mutex during reconnect
  CIFS: Fix a possible memory corruption during reconnect
  CIFS: Fix a possible memory corruption in push locks
  CIFS: Fix missing nls unload in smb2_reconnect()
  CIFS: Decrease verbosity of ioctl call
  SMB3: parsing for new snapshot timestamp mount parm

fs/cifs/cifsencrypt.c

@@ -699,11 +699,15 @@ setup_ntlmv2_rsp(struct cifs_ses *ses, const struct nls_table *nls_cp)
 
 	if (ses->server->negflavor == CIFS_NEGFLAVOR_EXTENDED) {
 		if (!ses->domainName) {
-			rc = find_domain_name(ses, nls_cp);
-			if (rc) {
-				cifs_dbg(VFS, "error %d finding domain name\n",
-					 rc);
-				goto setup_ntlmv2_rsp_ret;
+			if (ses->domainAuto) {
+				rc = find_domain_name(ses, nls_cp);
+				if (rc) {
+					cifs_dbg(VFS, "error %d finding domain name\n",
+						 rc);
+					goto setup_ntlmv2_rsp_ret;
+				}
+			} else {
+				ses->domainName = kstrdup("", GFP_KERNEL);
 			}
 		}
 	} else {

fs/cifs/cifsfs.c

@@ -615,7 +615,7 @@ cifs_get_root(struct smb_vol *vol, struct super_block *sb)
 		return dget(sb->s_root);
 
 	full_path = cifs_build_path_to_root(vol, cifs_sb,
-					    cifs_sb_master_tcon(cifs_sb));
+				cifs_sb_master_tcon(cifs_sb), 0);
 	if (full_path == NULL)
 		return ERR_PTR(-ENOMEM);
 

fs/cifs/cifsglob.h

@@ -514,6 +514,7 @@ struct smb_vol {
 	bool persistent:1;
 	bool nopersistent:1;
 	bool resilient:1; /* noresilient not required since not fored for CA */
+	bool domainauto:1;
 	unsigned int rsize;
 	unsigned int wsize;
 	bool sockopt_tcp_nodelay:1;
@@ -525,6 +526,7 @@ struct smb_vol {
 	struct sockaddr_storage srcaddr; /* allow binding to a local IP */
 	struct nls_table *local_nls;
 	unsigned int echo_interval; /* echo interval in secs */
+	__u64 snapshot_time; /* needed for timewarp tokens */
 	unsigned int max_credits; /* smb3 max_credits 10 < credits < 60000 */
 };
 
@@ -646,6 +648,8 @@ struct TCP_Server_Info {
 	unsigned int	max_read;
 	unsigned int	max_write;
 	__u8		preauth_hash[512];
+	struct delayed_work reconnect; /* reconnect workqueue job */
+	struct mutex reconnect_mutex; /* prevent simultaneous reconnects */
 #endif /* CONFIG_CIFS_SMB2 */
 	unsigned long echo_interval;
 };
@@ -827,6 +831,7 @@ struct cifs_ses {
 	enum securityEnum sectype; /* what security flavor was specified? */
 	bool sign;		/* is signing required? */
 	bool need_reconnect:1; /* connection reset, uid now invalid */
+	bool domainAuto:1;
 #ifdef CONFIG_CIFS_SMB2
 	__u16 session_flags;
 	__u8 smb3signingkey[SMB3_SIGN_KEY_SIZE];
@@ -849,6 +854,7 @@ cap_unix(struct cifs_ses *ses)
 struct cifs_tcon {
 	struct list_head tcon_list;
 	int tc_count;
+	struct list_head rlist; /* reconnect list */
 	struct list_head openFileList;
 	spinlock_t open_file_lock; /* protects list above */
 	struct cifs_ses *ses;	/* pointer to session associated with */
@@ -922,6 +928,7 @@ struct cifs_tcon {
 	bool broken_posix_open; /* e.g. Samba server versions < 3.3.2, 3.2.9 */
 	bool broken_sparse_sup; /* if server or share does not support sparse */
 	bool need_reconnect:1; /* connection reset, tid now invalid */
+	bool need_reopen_files:1; /* need to reopen tcon file handles */
 	bool use_resilient:1; /* use resilient instead of durable handles */
 	bool use_persistent:1; /* use persistent instead of durable handles */
 #ifdef CONFIG_CIFS_SMB2
@@ -932,6 +939,7 @@ struct cifs_tcon {
 	__u32 maximal_access;
 	__u32 vol_serial_number;
 	__le64 vol_create_time;
+	__u64 snapshot_time; /* for timewarp tokens - timestamp of snapshot */
 	__u32 ss_flags;		/* sector size flags */
 	__u32 perf_sector_size; /* best sector size for perf */
 	__u32 max_chunks;

fs/cifs/cifsproto.h

@@ -63,7 +63,8 @@ extern void exit_cifs_spnego(void);
 extern char *build_path_from_dentry(struct dentry *);
 extern char *cifs_build_path_to_root(struct smb_vol *vol,
 				     struct cifs_sb_info *cifs_sb,
-				     struct cifs_tcon *tcon);
+				     struct cifs_tcon *tcon,
+				     int add_treename);
 extern char *build_wildcard_path_from_dentry(struct dentry *direntry);
 extern char *cifs_compose_mount_options(const char *sb_mountdata,
 		const char *fullpath, const struct dfs_info3_param *ref,
@@ -206,6 +207,9 @@ extern void cifs_add_pending_open_locked(struct cifs_fid *fid,
 					 struct tcon_link *tlink,
 					 struct cifs_pending_open *open);
 extern void cifs_del_pending_open(struct cifs_pending_open *open);
+extern void cifs_put_tcp_session(struct TCP_Server_Info *server,
+				 int from_reconnect);
+extern void cifs_put_tcon(struct cifs_tcon *tcon);
 
 #if IS_ENABLED(CONFIG_CIFS_DFS_UPCALL)
 extern void cifs_dfs_release_automount_timer(void);

fs/cifs/connect.c

@@ -53,6 +53,9 @@
 #include "nterr.h"
 #include "rfc1002pdu.h"
 #include "fscache.h"
+#ifdef CONFIG_CIFS_SMB2
+#include "smb2proto.h"
+#endif
 
 #define CIFS_PORT 445
 #define RFC1001_PORT 139
@@ -89,13 +92,15 @@ enum {
 	Opt_multiuser, Opt_sloppy, Opt_nosharesock,
 	Opt_persistent, Opt_nopersistent,
 	Opt_resilient, Opt_noresilient,
+	Opt_domainauto,
 
 	/* Mount options which take numeric value */
 	Opt_backupuid, Opt_backupgid, Opt_uid,
 	Opt_cruid, Opt_gid, Opt_file_mode,
 	Opt_dirmode, Opt_port,
 	Opt_rsize, Opt_wsize, Opt_actimeo,
 	Opt_echo_interval, Opt_max_credits,
+	Opt_snapshot,
 
 	/* Mount options which take string value */
 	Opt_user, Opt_pass, Opt_ip,
@@ -177,6 +182,7 @@ static const match_table_t cifs_mount_option_tokens = {
 	{ Opt_nopersistent, "nopersistenthandles"},
 	{ Opt_resilient, "resilienthandles"},
 	{ Opt_noresilient, "noresilienthandles"},
+	{ Opt_domainauto, "domainauto"},
 
 	{ Opt_backupuid, "backupuid=%s" },
 	{ Opt_backupgid, "backupgid=%s" },
@@ -192,6 +198,7 @@ static const match_table_t cifs_mount_option_tokens = {
 	{ Opt_actimeo, "actimeo=%s" },
 	{ Opt_echo_interval, "echo_interval=%s" },
 	{ Opt_max_credits, "max_credits=%s" },
+	{ Opt_snapshot, "snapshot=%s" },
 
 	{ Opt_blank_user, "user=" },
 	{ Opt_blank_user, "username=" },
@@ -1500,6 +1507,9 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
 		case Opt_noresilient:
 			vol->resilient = false; /* already the default */
 			break;
+		case Opt_domainauto:
+			vol->domainauto = true;
+			break;
 
 		/* Numeric Values */
 		case Opt_backupuid:
@@ -1602,6 +1612,14 @@ cifs_parse_mount_options(const char *mountdata, const char *devname,
 			}
 			vol->echo_interval = option;
 			break;
+		case Opt_snapshot:
+			if (get_option_ul(args, &option)) {
+				cifs_dbg(VFS, "%s: Invalid snapshot time\n",
+					 __func__);
+				goto cifs_parse_mount_err;
+			}
+			vol->snapshot_time = option;
+			break;
 		case Opt_max_credits:
 			if (get_option_ul(args, &option) || (option < 20) ||
 			    (option > 60000)) {
@@ -2101,8 +2119,8 @@ cifs_find_tcp_session(struct smb_vol *vol)
 	return NULL;
 }
 
-static void
-cifs_put_tcp_session(struct TCP_Server_Info *server)
+void
+cifs_put_tcp_session(struct TCP_Server_Info *server, int from_reconnect)
 {
 	struct task_struct *task;
 
@@ -2119,6 +2137,19 @@ cifs_put_tcp_session(struct TCP_Server_Info *server)
 
 	cancel_delayed_work_sync(&server->echo);
 
+#ifdef CONFIG_CIFS_SMB2
+	if (from_reconnect)
+		/*
+		 * Avoid deadlock here: reconnect work calls
+		 * cifs_put_tcp_session() at its end. Need to be sure
+		 * that reconnect work does nothing with server pointer after
+		 * that step.
+		 */
+		cancel_delayed_work(&server->reconnect);
+	else
+		cancel_delayed_work_sync(&server->reconnect);
+#endif
+
 	spin_lock(&GlobalMid_Lock);
 	server->tcpStatus = CifsExiting;
 	spin_unlock(&GlobalMid_Lock);
@@ -2183,6 +2214,10 @@ cifs_get_tcp_session(struct smb_vol *volume_info)
 	INIT_LIST_HEAD(&tcp_ses->tcp_ses_list);
 	INIT_LIST_HEAD(&tcp_ses->smb_ses_list);
 	INIT_DELAYED_WORK(&tcp_ses->echo, cifs_echo_request);
+#ifdef CONFIG_CIFS_SMB2
+	INIT_DELAYED_WORK(&tcp_ses->reconnect, smb2_reconnect_server);
+	mutex_init(&tcp_ses->reconnect_mutex);
+#endif
 	memcpy(&tcp_ses->srcaddr, &volume_info->srcaddr,
 	       sizeof(tcp_ses->srcaddr));
 	memcpy(&tcp_ses->dstaddr, &volume_info->dstaddr,
@@ -2341,7 +2376,7 @@ cifs_put_smb_ses(struct cifs_ses *ses)
 	spin_unlock(&cifs_tcp_ses_lock);
 
 	sesInfoFree(ses);
-	cifs_put_tcp_session(server);
+	cifs_put_tcp_session(server, 0);
 }
 
 #ifdef CONFIG_KEYS
@@ -2515,7 +2550,7 @@ cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb_vol *volume_info)
 		mutex_unlock(&ses->session_mutex);
 
 		/* existing SMB ses has a server reference already */
-		cifs_put_tcp_session(server);
+		cifs_put_tcp_session(server, 0);
 		free_xid(xid);
 		return ses;
 	}
@@ -2549,6 +2584,8 @@ cifs_get_smb_ses(struct TCP_Server_Info *server, struct smb_vol *volume_info)
 		if (!ses->domainName)
 			goto get_ses_fail;
 	}
+	if (volume_info->domainauto)
+		ses->domainAuto = volume_info->domainauto;
 	ses->cred_uid = volume_info->cred_uid;
 	ses->linux_uid = volume_info->linux_uid;
 
@@ -2587,16 +2624,22 @@ static int match_tcon(struct cifs_tcon *tcon, const char *unc)
 }
 
 static struct cifs_tcon *
-cifs_find_tcon(struct cifs_ses *ses, const char *unc)
+cifs_find_tcon(struct cifs_ses *ses, struct smb_vol *volume_info)
 {
 	struct list_head *tmp;
 	struct cifs_tcon *tcon;
 
 	spin_lock(&cifs_tcp_ses_lock);
 	list_for_each(tmp, &ses->tcon_list) {
 		tcon = list_entry(tmp, struct cifs_tcon, tcon_list);
-		if (!match_tcon(tcon, unc))
+		if (!match_tcon(tcon, volume_info->UNC))
 			continue;
+
+#ifdef CONFIG_CIFS_SMB2
+		if (tcon->snapshot_time != volume_info->snapshot_time)
+			continue;
+#endif /* CONFIG_CIFS_SMB2 */
+
 		++tcon->tc_count;
 		spin_unlock(&cifs_tcp_ses_lock);
 		return tcon;
@@ -2605,7 +2648,7 @@ cifs_find_tcon(struct cifs_ses *ses, const char *unc)
 	return NULL;
 }
 
-static void
+void
 cifs_put_tcon(struct cifs_tcon *tcon)
 {
 	unsigned int xid;
@@ -2637,7 +2680,7 @@ cifs_get_tcon(struct cifs_ses *ses, struct smb_vol *volume_info)
 	int rc, xid;
 	struct cifs_tcon *tcon;
 
-	tcon = cifs_find_tcon(ses, volume_info->UNC);
+	tcon = cifs_find_tcon(ses, volume_info);
 	if (tcon) {
 		cifs_dbg(FYI, "Found match on UNC path\n");
 		/* existing tcon already has a reference */
@@ -2658,6 +2701,22 @@ cifs_get_tcon(struct cifs_ses *ses, struct smb_vol *volume_info)
 		goto out_fail;
 	}
 
+	if (volume_info->snapshot_time) {
+#ifdef CONFIG_CIFS_SMB2
+		if (ses->server->vals->protocol_id == 0) {
+			cifs_dbg(VFS,
+			     "Use SMB2 or later for snapshot mount option\n");
+			rc = -EOPNOTSUPP;
+			goto out_fail;
+		} else
+			tcon->snapshot_time = volume_info->snapshot_time;
+#else
+		cifs_dbg(VFS, "Snapshot mount option requires SMB2 support\n");
+		rc = -EOPNOTSUPP;
+		goto out_fail;
+#endif /* CONFIG_CIFS_SMB2 */
+	}
+
 	tcon->ses = ses;
 	if (volume_info->password) {
 		tcon->password = kstrdup(volume_info->password, GFP_KERNEL);
@@ -3707,7 +3766,8 @@ cifs_mount(struct cifs_sb_info *cifs_sb, struct smb_vol *volume_info)
 		/*
 		 * cifs_build_path_to_root works only when we have a valid tcon
 		 */
-		full_path = cifs_build_path_to_root(volume_info, cifs_sb, tcon);
+		full_path = cifs_build_path_to_root(volume_info, cifs_sb, tcon,
+					tcon->Flags & SMB_SHARE_IS_IN_DFS);
 		if (full_path == NULL) {
 			rc = -ENOMEM;
 			goto mount_fail_check;
@@ -3793,7 +3853,7 @@ cifs_mount(struct cifs_sb_info *cifs_sb, struct smb_vol *volume_info)
 		else if (ses)
 			cifs_put_smb_ses(ses);
 		else
-			cifs_put_tcp_session(server);
+			cifs_put_tcp_session(server, 0);
 		bdi_destroy(&cifs_sb->bdi);
 	}
 
@@ -4104,7 +4164,7 @@ cifs_construct_tcon(struct cifs_sb_info *cifs_sb, kuid_t fsuid)
 	ses = cifs_get_smb_ses(master_tcon->ses->server, vol_info);
 	if (IS_ERR(ses)) {
 		tcon = (struct cifs_tcon *)ses;
-		cifs_put_tcp_session(master_tcon->ses->server);
+		cifs_put_tcp_session(master_tcon->ses->server, 0);
 		goto out;
 	}
 

fs/cifs/dir.c

@@ -47,7 +47,7 @@ renew_parental_timestamps(struct dentry *direntry)
 
 char *
 cifs_build_path_to_root(struct smb_vol *vol, struct cifs_sb_info *cifs_sb,
-			struct cifs_tcon *tcon)
+			struct cifs_tcon *tcon, int add_treename)
 {
 	int pplen = vol->prepath ? strlen(vol->prepath) + 1 : 0;
 	int dfsplen;
@@ -59,7 +59,7 @@ cifs_build_path_to_root(struct smb_vol *vol, struct cifs_sb_info *cifs_sb,
 		return full_path;
 	}
 
-	if (tcon->Flags & SMB_SHARE_IS_IN_DFS)
+	if (add_treename)
 		dfsplen = strnlen(tcon->treeName, MAX_TREE_SIZE + 1);
 	else
 		dfsplen = 0;

fs/cifs/file.c

@@ -777,6 +777,11 @@ cifs_reopen_persistent_handles(struct cifs_tcon *tcon)
 	struct list_head *tmp1;
 	struct list_head tmp_list;
 
+	if (!tcon->use_persistent || !tcon->need_reopen_files)
+		return;
+
+	tcon->need_reopen_files = false;
+
 	cifs_dbg(FYI, "Reopen persistent handles");
 	INIT_LIST_HEAD(&tmp_list);
 
@@ -793,7 +798,8 @@ cifs_reopen_persistent_handles(struct cifs_tcon *tcon)
 
 	list_for_each_safe(tmp, tmp1, &tmp_list) {
 		open_file = list_entry(tmp, struct cifsFileInfo, rlist);
-		cifs_reopen_file(open_file, false /* do not flush */);
+		if (cifs_reopen_file(open_file, false /* do not flush */))
+			tcon->need_reopen_files = true;
 		list_del_init(&open_file->rlist);
 		cifsFileInfo_put(open_file);
 	}

fs/cifs/ioctl.c

@@ -189,7 +189,7 @@ long cifs_ioctl(struct file *filep, unsigned int command, unsigned long arg)
 	xid = get_xid();
 
 	cifs_sb = CIFS_SB(inode->i_sb);
-	cifs_dbg(VFS, "cifs ioctl 0x%x\n", command);
+	cifs_dbg(FYI, "cifs ioctl 0x%x\n", command);
 	switch (command) {
 		case FS_IOC_GETFLAGS:
 			if (pSMBFile == NULL)