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authorLinus Torvalds <torvalds@linux-foundation.org>2017-09-14 18:54:01 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-09-14 18:54:01 -0700
commit0f0d12728e56c94d3289c6831243b6faeae8a19d (patch)
treebd52fd4ed6fba2a0d8bb95e7fc33f51ac299001d /fs/namespace.c
parent581bfce969cbfc7ce43ee92273be9cb7c3fdfa61 (diff)
parente462ec50cb5fad19f6003a3d8087f4a0945dd2b1 (diff)
downloadlinux-0f0d12728e56c94d3289c6831243b6faeae8a19d.tar.gz
Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull mount flag updates from Al Viro:
 "Another chunk of fmount preparations from dhowells; only trivial
  conflicts for that part. It separates MS_... bits (very grotty
  mount(2) ABI) from the struct super_block ->s_flags (kernel-internal,
  only a small subset of MS_... stuff).

  This does *not* convert the filesystems to new constants; only the
  infrastructure is done here. The next step in that series is where the
  conflicts would be; that's the conversion of filesystems. It's purely
  mechanical and it's better done after the merge, so if you could run
  something like

	list=$(for i in MS_RDONLY MS_NOSUID MS_NODEV MS_NOEXEC MS_SYNCHRONOUS MS_MANDLOCK MS_DIRSYNC MS_NOATIME MS_NODIRATIME MS_SILENT MS_POSIXACL MS_KERNMOUNT MS_I_VERSION MS_LAZYTIME; do git grep -l $i fs drivers/staging/lustre drivers/mtd ipc mm include/linux; done|sort|uniq|grep -v '^fs/namespace.c$')

	sed -i -e 's/\<MS_RDONLY\>/SB_RDONLY/g' \
	        -e 's/\<MS_NOSUID\>/SB_NOSUID/g' \
	        -e 's/\<MS_NODEV\>/SB_NODEV/g' \
	        -e 's/\<MS_NOEXEC\>/SB_NOEXEC/g' \
	        -e 's/\<MS_SYNCHRONOUS\>/SB_SYNCHRONOUS/g' \
	        -e 's/\<MS_MANDLOCK\>/SB_MANDLOCK/g' \
	        -e 's/\<MS_DIRSYNC\>/SB_DIRSYNC/g' \
	        -e 's/\<MS_NOATIME\>/SB_NOATIME/g' \
	        -e 's/\<MS_NODIRATIME\>/SB_NODIRATIME/g' \
	        -e 's/\<MS_SILENT\>/SB_SILENT/g' \
	        -e 's/\<MS_POSIXACL\>/SB_POSIXACL/g' \
	        -e 's/\<MS_KERNMOUNT\>/SB_KERNMOUNT/g' \
	        -e 's/\<MS_I_VERSION\>/SB_I_VERSION/g' \
	        -e 's/\<MS_LAZYTIME\>/SB_LAZYTIME/g' \
	        $list

  and commit it with something along the lines of 'convert filesystems
  away from use of MS_... constants' as commit message, it would save a
  quite a bit of headache next cycle"

* 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  VFS: Differentiate mount flags (MS_*) from internal superblock flags
  VFS: Convert sb->s_flags & MS_RDONLY to sb_rdonly(sb)
  vfs: Add sb_rdonly(sb) to query the MS_RDONLY flag on s_flags
Diffstat (limited to 'fs/namespace.c')
-rw-r--r--fs/namespace.c62
1 files changed, 34 insertions, 28 deletions
diff --git a/fs/namespace.c b/fs/namespace.c
index df0f7521979a..e48ad0192d81 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -275,7 +275,7 @@ int __mnt_is_readonly(struct vfsmount *mnt)
 {
 	if (mnt->mnt_flags & MNT_READONLY)
 		return 1;
-	if (mnt->mnt_sb->s_flags & MS_RDONLY)
+	if (sb_rdonly(mnt->mnt_sb))
 		return 1;
 	return 0;
 }
@@ -1029,7 +1029,7 @@ vfs_kern_mount(struct file_system_type *type, int flags, const char *name, void
 	if (!mnt)
 		return ERR_PTR(-ENOMEM);
 
-	if (flags & MS_KERNMOUNT)
+	if (flags & SB_KERNMOUNT)
 		mnt->mnt.mnt_flags = MNT_INTERNAL;
 
 	root = mount_fs(type, flags, name, data);
@@ -1061,7 +1061,7 @@ vfs_submount(const struct dentry *mountpoint, struct file_system_type *type,
 	if (mountpoint->d_sb->s_user_ns != &init_user_ns)
 		return ERR_PTR(-EPERM);
 
-	return vfs_kern_mount(type, MS_SUBMOUNT, name, data);
+	return vfs_kern_mount(type, SB_SUBMOUNT, name, data);
 }
 EXPORT_SYMBOL_GPL(vfs_submount);
 
@@ -1592,8 +1592,8 @@ static int do_umount(struct mount *mnt, int flags)
 		if (!capable(CAP_SYS_ADMIN))
 			return -EPERM;
 		down_write(&sb->s_umount);
-		if (!(sb->s_flags & MS_RDONLY))
-			retval = do_remount_sb(sb, MS_RDONLY, NULL, 0);
+		if (!sb_rdonly(sb))
+			retval = do_remount_sb(sb, SB_RDONLY, NULL, 0);
 		up_write(&sb->s_umount);
 		return retval;
 	}
@@ -2117,7 +2117,7 @@ static void unlock_mount(struct mountpoint *where)
 
 static int graft_tree(struct mount *mnt, struct mount *p, struct mountpoint *mp)
 {
-	if (mnt->mnt.mnt_sb->s_flags & MS_NOUSER)
+	if (mnt->mnt.mnt_sb->s_flags & SB_NOUSER)
 		return -EINVAL;
 
 	if (d_is_dir(mp->m_dentry) !=
@@ -2131,9 +2131,9 @@ static int graft_tree(struct mount *mnt, struct mount *p, struct mountpoint *mp)
  * Sanity check the flags to change_mnt_propagation.
  */
 
-static int flags_to_propagation_type(int flags)
+static int flags_to_propagation_type(int ms_flags)
 {
-	int type = flags & ~(MS_REC | MS_SILENT);
+	int type = ms_flags & ~(MS_REC | MS_SILENT);
 
 	/* Fail if any non-propagation flags are set */
 	if (type & ~(MS_SHARED | MS_PRIVATE | MS_SLAVE | MS_UNBINDABLE))
@@ -2147,18 +2147,18 @@ static int flags_to_propagation_type(int flags)
 /*
  * recursively change the type of the mountpoint.
  */
-static int do_change_type(struct path *path, int flag)
+static int do_change_type(struct path *path, int ms_flags)
 {
 	struct mount *m;
 	struct mount *mnt = real_mount(path->mnt);
-	int recurse = flag & MS_REC;
+	int recurse = ms_flags & MS_REC;
 	int type;
 	int err = 0;
 
 	if (path->dentry != path->mnt->mnt_root)
 		return -EINVAL;
 
-	type = flags_to_propagation_type(flag);
+	type = flags_to_propagation_type(ms_flags);
 	if (!type)
 		return -EINVAL;
 
@@ -2280,8 +2280,8 @@ static int change_mount_flags(struct vfsmount *mnt, int ms_flags)
  * If you've mounted a non-root directory somewhere and want to do remount
  * on it - tough luck.
  */
-static int do_remount(struct path *path, int flags, int mnt_flags,
-		      void *data)
+static int do_remount(struct path *path, int ms_flags, int sb_flags,
+		      int mnt_flags, void *data)
 {
 	int err;
 	struct super_block *sb = path->mnt->mnt_sb;
@@ -2325,12 +2325,12 @@ static int do_remount(struct path *path, int flags, int mnt_flags,
 		return err;
 
 	down_write(&sb->s_umount);
-	if (flags & MS_BIND)
-		err = change_mount_flags(path->mnt, flags);
+	if (ms_flags & MS_BIND)
+		err = change_mount_flags(path->mnt, ms_flags);
 	else if (!capable(CAP_SYS_ADMIN))
 		err = -EPERM;
 	else
-		err = do_remount_sb(sb, flags, data, 0);
+		err = do_remount_sb(sb, sb_flags, data, 0);
 	if (!err) {
 		lock_mount_hash();
 		mnt_flags |= mnt->mnt.mnt_flags & ~MNT_USER_SETTABLE_MASK;
@@ -2495,7 +2495,7 @@ static bool mount_too_revealing(struct vfsmount *mnt, int *new_mnt_flags);
  * create a new mount for userspace and request it to be added into the
  * namespace's tree
  */
-static int do_new_mount(struct path *path, const char *fstype, int flags,
+static int do_new_mount(struct path *path, const char *fstype, int sb_flags,
 			int mnt_flags, const char *name, void *data)
 {
 	struct file_system_type *type;
@@ -2509,7 +2509,7 @@ static int do_new_mount(struct path *path, const char *fstype, int flags,
 	if (!type)
 		return -ENODEV;
 
-	mnt = vfs_kern_mount(type, flags, name, data);
+	mnt = vfs_kern_mount(type, sb_flags, name, data);
 	if (!IS_ERR(mnt) && (type->fs_flags & FS_HAS_SUBTYPE) &&
 	    !mnt->mnt_sb->s_subtype)
 		mnt = fs_set_subtype(mnt, fstype);
@@ -2764,8 +2764,8 @@ long do_mount(const char *dev_name, const char __user *dir_name,
 		const char *type_page, unsigned long flags, void *data_page)
 {
 	struct path path;
+	unsigned int mnt_flags = 0, sb_flags;
 	int retval = 0;
-	int mnt_flags = 0;
 
 	/* Discard magic */
 	if ((flags & MS_MGC_MSK) == MS_MGC_VAL)
@@ -2775,6 +2775,9 @@ long do_mount(const char *dev_name, const char __user *dir_name,
 	if (data_page)
 		((char *)data_page)[PAGE_SIZE - 1] = 0;
 
+	if (flags & MS_NOUSER)
+		return -EINVAL;
+
 	/* ... and get the mountpoint */
 	retval = user_path(dir_name, &path);
 	if (retval)
@@ -2784,7 +2787,7 @@ long do_mount(const char *dev_name, const char __user *dir_name,
 				   type_page, flags, data_page);
 	if (!retval && !may_mount())
 		retval = -EPERM;
-	if (!retval && (flags & MS_MANDLOCK) && !may_mandlock())
+	if (!retval && (flags & SB_MANDLOCK) && !may_mandlock())
 		retval = -EPERM;
 	if (retval)
 		goto dput_out;
@@ -2806,7 +2809,7 @@ long do_mount(const char *dev_name, const char __user *dir_name,
 		mnt_flags |= MNT_NODIRATIME;
 	if (flags & MS_STRICTATIME)
 		mnt_flags &= ~(MNT_RELATIME | MNT_NOATIME);
-	if (flags & MS_RDONLY)
+	if (flags & SB_RDONLY)
 		mnt_flags |= MNT_READONLY;
 
 	/* The default atime for remount is preservation */
@@ -2817,12 +2820,15 @@ long do_mount(const char *dev_name, const char __user *dir_name,
 		mnt_flags |= path.mnt->mnt_flags & MNT_ATIME_MASK;
 	}
 
-	flags &= ~(MS_NOSUID | MS_NOEXEC | MS_NODEV | MS_ACTIVE | MS_BORN |
-		   MS_NOATIME | MS_NODIRATIME | MS_RELATIME| MS_KERNMOUNT |
-		   MS_STRICTATIME | MS_NOREMOTELOCK | MS_SUBMOUNT);
+	sb_flags = flags & (SB_RDONLY |
+			    SB_SYNCHRONOUS |
+			    SB_MANDLOCK |
+			    SB_DIRSYNC |
+			    SB_SILENT |
+			    SB_POSIXACL);
 
 	if (flags & MS_REMOUNT)
-		retval = do_remount(&path, flags & ~MS_REMOUNT, mnt_flags,
+		retval = do_remount(&path, flags, sb_flags, mnt_flags,
 				    data_page);
 	else if (flags & MS_BIND)
 		retval = do_loopback(&path, dev_name, flags & MS_REC);
@@ -2831,7 +2837,7 @@ long do_mount(const char *dev_name, const char __user *dir_name,
 	else if (flags & MS_MOVE)
 		retval = do_move_mount(&path, dev_name);
 	else
-		retval = do_new_mount(&path, type_page, flags, mnt_flags,
+		retval = do_new_mount(&path, type_page, sb_flags, mnt_flags,
 				      dev_name, data_page);
 dput_out:
 	path_put(&path);
@@ -3281,7 +3287,7 @@ void put_mnt_ns(struct mnt_namespace *ns)
 struct vfsmount *kern_mount_data(struct file_system_type *type, void *data)
 {
 	struct vfsmount *mnt;
-	mnt = vfs_kern_mount(type, MS_KERNMOUNT, type->name, data);
+	mnt = vfs_kern_mount(type, SB_KERNMOUNT, type->name, data);
 	if (!IS_ERR(mnt)) {
 		/*
 		 * it is a longterm mount, don't release mnt until
@@ -3358,7 +3364,7 @@ static bool mnt_already_visible(struct mnt_namespace *ns, struct vfsmount *new,
 		mnt_flags = mnt->mnt.mnt_flags;
 
 		/* Don't miss readonly hidden in the superblock flags */
-		if (mnt->mnt.mnt_sb->s_flags & MS_RDONLY)
+		if (sb_rdonly(mnt->mnt.mnt_sb))
 			mnt_flags |= MNT_LOCK_READONLY;
 
 		/* Verify the mount flags are equal to or more permissive