Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6:
  cifs: propagate errors from cifs_get_root() to mount(2)
  cifs: tidy cifs_do_mount() up a bit
  cifs: more breakage on mount failures
  cifs: close sget() races
  cifs: pull freeing mountdata/dropping nls/freeing cifs_sb into cifs_umount()
  cifs: move cifs_umount() call into ->kill_sb()
  cifs: pull cifs_mount() call up
  sanitize cifs_umount() prototype
  cifs: initialize ->tlink_tree in cifs_setup_cifs_sb()
  cifs: allocate mountdata earlier
  cifs: leak on mount if we share superblock
  cifs: don't pass superblock to cifs_mount()
  cifs: don't leak nls on mount failure
  cifs: double free on mount failure
  take bdi setup/destruction into cifs_mount/cifs_umount

Acked-by: Steve French <smfrench@gmail.com>

4 files changed, 98 insertions, 116 deletions

diff --git a/fs/cifs/cifs_fs_sb.h b/fs/cifs/cifs_fs_sb.h
index ffb1459dc6e..7260e11e21f 100644
--- a/fs/cifs/cifs_fs_sb.h
+++ b/fs/cifs/cifs_fs_sb.h
@@ -42,6 +42,7 @@
 #define CIFS_MOUNT_MULTIUSER	0x20000 /* multiuser mount */
 #define CIFS_MOUNT_STRICT_IO	0x40000 /* strict cache mode */
 #define CIFS_MOUNT_RWPIDFORWARD	0x80000 /* use pid forwarding for rw */
+#define CIFS_MOUNT_POSIXACL	0x100000 /* mirror of MS_POSIXACL in mnt_cifs_flags */
 
 struct cifs_sb_info {
 	struct rb_root tlink_tree;
diff --git a/fs/cifs/cifsfs.c b/fs/cifs/cifsfs.c
index 2f0c58646c1..35f9154615f 100644
--- a/fs/cifs/cifsfs.c
+++ b/fs/cifs/cifsfs.c
@@ -104,8 +104,7 @@ cifs_sb_deactive(struct super_block *sb)
 }
 
 static int
-cifs_read_super(struct super_block *sb, struct smb_vol *volume_info,
-		const char *devname, int silent)
+cifs_read_super(struct super_block *sb)
 {
 	struct inode *inode;
 	struct cifs_sb_info *cifs_sb;
@@ -113,22 +112,16 @@ cifs_read_super(struct super_block *sb, struct smb_vol *volume_info,
 
 	cifs_sb = CIFS_SB(sb);
 
-	spin_lock_init(&cifs_sb->tlink_tree_lock);
-	cifs_sb->tlink_tree = RB_ROOT;
+	if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIXACL)
+		sb->s_flags |= MS_POSIXACL;
 
-	rc = bdi_setup_and_register(&cifs_sb->bdi, "cifs", BDI_CAP_MAP_COPY);
-	if (rc)
-		return rc;
-
-	cifs_sb->bdi.ra_pages = default_backing_dev_info.ra_pages;
+	if (cifs_sb_master_tcon(cifs_sb)->ses->capabilities & CAP_LARGE_FILES)
+		sb->s_maxbytes = MAX_LFS_FILESIZE;
+	else
+		sb->s_maxbytes = MAX_NON_LFS;
 
-	rc = cifs_mount(sb, cifs_sb, volume_info, devname);
-
-	if (rc) {
-		if (!silent)
-			cERROR(1, "cifs_mount failed w/return code = %d", rc);
-		goto out_mount_failed;
-	}
+	/* BB FIXME fix time_gran to be larger for LANMAN sessions */
+	sb->s_time_gran = 100;
 
 	sb->s_magic = CIFS_MAGIC_NUMBER;
 	sb->s_op = &cifs_super_ops;
@@ -170,37 +163,14 @@ out_no_root:
 	if (inode)
 		iput(inode);
 
-	cifs_umount(sb, cifs_sb);
-
-out_mount_failed:
-	bdi_destroy(&cifs_sb->bdi);
 	return rc;
 }
 
-static void
-cifs_put_super(struct super_block *sb)
+static void cifs_kill_sb(struct super_block *sb)
 {
-	int rc = 0;
-	struct cifs_sb_info *cifs_sb;
-
-	cFYI(1, "In cifs_put_super");
-	cifs_sb = CIFS_SB(sb);
-	if (cifs_sb == NULL) {
-		cFYI(1, "Empty cifs superblock info passed to unmount");
-		return;
-	}
-
-	rc = cifs_umount(sb, cifs_sb);
-	if (rc)
-		cERROR(1, "cifs_umount failed with return code %d", rc);
-	if (cifs_sb->mountdata) {
-		kfree(cifs_sb->mountdata);
-		cifs_sb->mountdata = NULL;
-	}
-
-	unload_nls(cifs_sb->local_nls);
-	bdi_destroy(&cifs_sb->bdi);
-	kfree(cifs_sb);
+	struct cifs_sb_info *cifs_sb = CIFS_SB(sb);
+	kill_anon_super(sb);
+	cifs_umount(cifs_sb);
 }
 
 static int
@@ -548,7 +518,6 @@ static int cifs_drop_inode(struct inode *inode)
 }
 
 static const struct super_operations cifs_super_ops = {
-	.put_super = cifs_put_super,
 	.statfs = cifs_statfs,
 	.alloc_inode = cifs_alloc_inode,
 	.destroy_inode = cifs_destroy_inode,
@@ -585,7 +554,7 @@ cifs_get_root(struct smb_vol *vol, struct super_block *sb)
 	full_path = cifs_build_path_to_root(vol, cifs_sb,
 					    cifs_sb_master_tcon(cifs_sb));
 	if (full_path == NULL)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 	cFYI(1, "Get root dentry for %s", full_path);
 
@@ -614,7 +583,7 @@ cifs_get_root(struct smb_vol *vol, struct super_block *sb)
 			dchild = d_alloc(dparent, &name);
 			if (dchild == NULL) {
 				dput(dparent);
-				dparent = NULL;
+				dparent = ERR_PTR(-ENOMEM);
 				goto out;
 			}
 		}
@@ -632,7 +601,7 @@ cifs_get_root(struct smb_vol *vol, struct super_block *sb)
 			if (rc) {
 				dput(dchild);
 				dput(dparent);
-				dparent = NULL;
+				dparent = ERR_PTR(rc);
 				goto out;
 			}
 			alias = d_materialise_unique(dchild, inode);
@@ -640,7 +609,7 @@ cifs_get_root(struct smb_vol *vol, struct super_block *sb)
 				dput(dchild);
 				if (IS_ERR(alias)) {
 					dput(dparent);
-					dparent = NULL;
+					dparent = ERR_PTR(-EINVAL); /* XXX */
 					goto out;
 				}
 				dchild = alias;
@@ -660,6 +629,13 @@ out:
 	return dparent;
 }
 
+static int cifs_set_super(struct super_block *sb, void *data)
+{
+	struct cifs_mnt_data *mnt_data = data;
+	sb->s_fs_info = mnt_data->cifs_sb;
+	return set_anon_super(sb, NULL);
+}
+
 static struct dentry *
 cifs_do_mount(struct file_system_type *fs_type,
 	      int flags, const char *dev_name, void *data)
@@ -680,75 +656,73 @@ cifs_do_mount(struct file_system_type *fs_type,
 	cifs_sb = kzalloc(sizeof(struct cifs_sb_info), GFP_KERNEL);
 	if (cifs_sb == NULL) {
 		root = ERR_PTR(-ENOMEM);
-		goto out;
+		goto out_nls;
+	}
+
+	cifs_sb->mountdata = kstrndup(data, PAGE_SIZE, GFP_KERNEL);
+	if (cifs_sb->mountdata == NULL) {
+		root = ERR_PTR(-ENOMEM);
+		goto out_cifs_sb;
 	}
 
 	cifs_setup_cifs_sb(volume_info, cifs_sb);
 
+	rc = cifs_mount(cifs_sb, volume_info);
+	if (rc) {
+		if (!(flags & MS_SILENT))
+			cERROR(1, "cifs_mount failed w/return code = %d", rc);
+		root = ERR_PTR(rc);
+		goto out_mountdata;
+	}
+
 	mnt_data.vol = volume_info;
 	mnt_data.cifs_sb = cifs_sb;
 	mnt_data.flags = flags;
 
-	sb = sget(fs_type, cifs_match_super, set_anon_super, &mnt_data);
+	sb = sget(fs_type, cifs_match_super, cifs_set_super, &mnt_data);
 	if (IS_ERR(sb)) {
 		root = ERR_CAST(sb);
-		goto out_cifs_sb;
+		cifs_umount(cifs_sb);
+		goto out;
 	}
 
-	if (sb->s_fs_info) {
+	if (sb->s_root) {
 		cFYI(1, "Use existing superblock");
-		goto out_shared;
-	}
-
-	/*
-	 * Copy mount params for use in submounts. Better to do
-	 * the copy here and deal with the error before cleanup gets
-	 * complicated post-mount.
-	 */
-	cifs_sb->mountdata = kstrndup(data, PAGE_SIZE, GFP_KERNEL);
-	if (cifs_sb->mountdata == NULL) {
-		root = ERR_PTR(-ENOMEM);
-		goto out_super;
-	}
-
-	sb->s_flags = flags;
-	/* BB should we make this contingent on mount parm? */
-	sb->s_flags |= MS_NODIRATIME | MS_NOATIME;
-	sb->s_fs_info = cifs_sb;
+		cifs_umount(cifs_sb);
+	} else {
+		sb->s_flags = flags;
+		/* BB should we make this contingent on mount parm? */
+		sb->s_flags |= MS_NODIRATIME | MS_NOATIME;
+
+		rc = cifs_read_super(sb);
+		if (rc) {
+			root = ERR_PTR(rc);
+			goto out_super;
+		}
 
-	rc = cifs_read_super(sb, volume_info, dev_name,
-			     flags & MS_SILENT ? 1 : 0);
-	if (rc) {
-		root = ERR_PTR(rc);
-		goto out_super;
+		sb->s_flags |= MS_ACTIVE;
 	}
 
-	sb->s_flags |= MS_ACTIVE;
-
 	root = cifs_get_root(volume_info, sb);
-	if (root == NULL)
+	if (IS_ERR(root))
 		goto out_super;
 
 	cFYI(1, "dentry root is: %p", root);
 	goto out;
 
-out_shared:
-	root = cifs_get_root(volume_info, sb);
-	if (root)
-		cFYI(1, "dentry root is: %p", root);
-	goto out;
-
 out_super:
-	kfree(cifs_sb->mountdata);
 	deactivate_locked_super(sb);
-
-out_cifs_sb:
-	unload_nls(cifs_sb->local_nls);
-	kfree(cifs_sb);
-
 out:
 	cifs_cleanup_volume_info(&volume_info);
 	return root;
+
+out_mountdata:
+	kfree(cifs_sb->mountdata);
+out_cifs_sb:
+	kfree(cifs_sb);
+out_nls:
+	unload_nls(volume_info->local_nls);
+	goto out;
 }
 
 static ssize_t cifs_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
@@ -837,7 +811,7 @@ struct file_system_type cifs_fs_type = {
 	.owner = THIS_MODULE,
 	.name = "cifs",
 	.mount = cifs_do_mount,
-	.kill_sb = kill_anon_super,
+	.kill_sb = cifs_kill_sb,
 	/*  .fs_flags */
 };
 const struct inode_operations cifs_dir_inode_ops = {
diff --git a/fs/cifs/cifsproto.h b/fs/cifs/cifsproto.h
index 953f84413c7..257f312ede4 100644
--- a/fs/cifs/cifsproto.h
+++ b/fs/cifs/cifsproto.h
@@ -157,9 +157,8 @@ extern int cifs_match_super(struct super_block *, void *);
 extern void cifs_cleanup_volume_info(struct smb_vol **pvolume_info);
 extern int cifs_setup_volume_info(struct smb_vol **pvolume_info,
 				  char *mount_data, const char *devname);
-extern int cifs_mount(struct super_block *, struct cifs_sb_info *,
-		      struct smb_vol *, const char *);
-extern int cifs_umount(struct super_block *, struct cifs_sb_info *);
+extern int cifs_mount(struct cifs_sb_info *, struct smb_vol *);
+extern void cifs_umount(struct cifs_sb_info *);
 extern void cifs_dfs_release_automount_timer(void);
 void cifs_proc_init(void);
 void cifs_proc_clean(void);
@@ -218,7 +217,8 @@ extern int get_dfs_path(int xid, struct cifs_ses *pSesInfo,
 			struct dfs_info3_param **preferrals,
 			int remap);
 extern void reset_cifs_unix_caps(int xid, struct cifs_tcon *tcon,
-				 struct super_block *sb, struct smb_vol *vol);
+				 struct cifs_sb_info *cifs_sb,
+				 struct smb_vol *vol);
 extern int CIFSSMBQFSInfo(const int xid, struct cifs_tcon *tcon,
 			struct kstatfs *FSData);
 extern int SMBOldQFSInfo(const int xid, struct cifs_tcon *tcon,
diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
index c761935eab8..7f540df5252 100644
--- a/fs/cifs/connect.c
+++ b/fs/cifs/connect.c
@@ -2546,7 +2546,7 @@ ip_connect(struct TCP_Server_Info *server)
 }
 
 void reset_cifs_unix_caps(int xid, struct cifs_tcon *tcon,
-			  struct super_block *sb, struct smb_vol *vol_info)
+			  struct cifs_sb_info *cifs_sb, struct smb_vol *vol_info)
 {
 	/* if we are reconnecting then should we check to see if
 	 * any requested capabilities changed locally e.g. via
@@ -2600,22 +2600,23 @@ void reset_cifs_unix_caps(int xid, struct cifs_tcon *tcon,
 			cap &= ~CIFS_UNIX_POSIX_ACL_CAP;
 		else if (CIFS_UNIX_POSIX_ACL_CAP & cap) {
 			cFYI(1, "negotiated posix acl support");
-			if (sb)
-				sb->s_flags |= MS_POSIXACL;
+			if (cifs_sb)
+				cifs_sb->mnt_cifs_flags |=
+					CIFS_MOUNT_POSIXACL;
 		}
 
 		if (vol_info && vol_info->posix_paths == 0)
 			cap &= ~CIFS_UNIX_POSIX_PATHNAMES_CAP;
 		else if (cap & CIFS_UNIX_POSIX_PATHNAMES_CAP) {
 			cFYI(1, "negotiate posix pathnames");
-			if (sb)
-				CIFS_SB(sb)->mnt_cifs_flags |=
+			if (cifs_sb)
+				cifs_sb->mnt_cifs_flags |=
 					CIFS_MOUNT_POSIX_PATHS;
 		}
 
-		if (sb && (CIFS_SB(sb)->rsize > 127 * 1024)) {
+		if (cifs_sb && (cifs_sb->rsize > 127 * 1024)) {
 			if ((cap & CIFS_UNIX_LARGE_READ_CAP) == 0) {
-				CIFS_SB(sb)->rsize = 127 * 1024;
+				cifs_sb->rsize = 127 * 1024;
 				cFYI(DBG2, "larger reads not supported by srv");
 			}
 		}
@@ -2662,6 +2663,9 @@ void cifs_setup_cifs_sb(struct smb_vol *pvolume_info,
 {
 	INIT_DELAYED_WORK(&cifs_sb->prune_tlinks, cifs_prune_tlinks);
 
+	spin_lock_init(&cifs_sb->tlink_tree_lock);
+	cifs_sb->tlink_tree = RB_ROOT;
+
 	if (pvolume_info->rsize > CIFSMaxBufSize) {
 		cERROR(1, "rsize %d too large, using MaxBufSize",
 			pvolume_info->rsize);
@@ -2982,8 +2986,7 @@ out:
 }
 
 int
-cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
-	   struct smb_vol *volume_info, const char *devname)
+cifs_mount(struct cifs_sb_info *cifs_sb, struct smb_vol *volume_info)
 {
 	int rc = 0;
 	int xid;
@@ -2994,6 +2997,13 @@ cifs_mount(struct super_block *sb, struct cifs_sb_info *cifs_sb,
 	struct tcon_link *tlink;
 #ifdef CONFIG_CIFS_DFS_UPCALL
 	int referral_walks_count = 0;
+
+	rc = bdi_setup_and_register(&cifs_sb->bdi, "cifs", BDI_CAP_MAP_COPY);
+	if (rc)
+		return rc;
+
+	cifs_sb->bdi.ra_pages = default_backing_dev_info.ra_pages;
+
 try_mount_again:
 	/* cleanup activities if we're chasing a referral */
 	if (referral_walks_count) {
@@ -3018,6 +3028,7 @@ try_mount_again:
 	srvTcp = cifs_get_tcp_session(volume_info);
 	if (IS_ERR(srvTcp)) {
 		rc = PTR_ERR(srvTcp);
+		bdi_destroy(&cifs_sb->bdi);
 		goto out;
 	}
 
@@ -3029,14 +3040,6 @@ try_mount_again:
 		goto mount_fail_check;
 	}
 
-	if (pSesInfo->capabilities & CAP_LARGE_FILES)
-		sb->s_maxbytes = MAX_LFS_FILESIZE;
-	else
-		sb->s_maxbytes = MAX_NON_LFS;
-
-	/* BB FIXME fix time_gran to be larger for LANMAN sessions */
-	sb->s_time_gran = 100;
-
 	/* search for existing tcon to this server share */
 	tcon = cifs_get_tcon(pSesInfo, volume_info);
 	if (IS_ERR(tcon)) {
@@ -3049,7 +3052,7 @@ try_mount_again:
 	if (tcon->ses->capabilities & CAP_UNIX) {
 		/* reset of caps checks mount to see if unix extensions
 		   disabled for just this mount */
-		reset_cifs_unix_caps(xid, tcon, sb, volume_info);
+		reset_cifs_unix_caps(xid, tcon, cifs_sb, volume_info);
 		if ((tcon->ses->server->tcpStatus == CifsNeedReconnect) &&
 		    (le64_to_cpu(tcon->fsUnixInfo.Capability) &
 		     CIFS_UNIX_TRANSPORT_ENCRYPTION_MANDATORY_CAP)) {
@@ -3172,6 +3175,7 @@ mount_fail_check:
 			cifs_put_smb_ses(pSesInfo);
 		else
 			cifs_put_tcp_session(srvTcp);
+		bdi_destroy(&cifs_sb->bdi);
 		goto out;
 	}
 
@@ -3346,8 +3350,8 @@ CIFSTCon(unsigned int xid, struct cifs_ses *ses,
 	return rc;
 }
 
-int
-cifs_umount(struct super_block *sb, struct cifs_sb_info *cifs_sb)
+void
+cifs_umount(struct cifs_sb_info *cifs_sb)
 {
 	struct rb_root *root = &cifs_sb->tlink_tree;
 	struct rb_node *node;
@@ -3368,7 +3372,10 @@ cifs_umount(struct super_block *sb, struct cifs_sb_info *cifs_sb)
 	}
 	spin_unlock(&cifs_sb->tlink_tree_lock);
 
-	return 0;
+	bdi_destroy(&cifs_sb->bdi);
+	kfree(cifs_sb->mountdata);
+	unload_nls(cifs_sb->local_nls);
+	kfree(cifs_sb);
 }
 
 int cifs_negotiate_protocol(unsigned int xid, struct cifs_ses *ses)