1 files changed, 297 insertions, 195 deletions

diff --git a/fs/fat/file.c b/fs/fat/file.c
index c614175876e..85f79a89e74 100644
--- a/fs/fat/file.c
+++ b/fs/fat/file.c
@@ -8,132 +8,179 @@
 
 #include <linux/capability.h>
 #include <linux/module.h>
+#include <linux/compat.h>
+#include <linux/mount.h>
 #include <linux/time.h>
-#include <linux/msdos_fs.h>
-#include <linux/smp_lock.h>
 #include <linux/buffer_head.h>
 #include <linux/writeback.h>
 #include <linux/backing-dev.h>
 #include <linux/blkdev.h>
+#include <linux/fsnotify.h>
+#include <linux/security.h>
+#include "fat.h"
 
-int fat_generic_ioctl(struct inode *inode, struct file *filp,
-		      unsigned int cmd, unsigned long arg)
+static int fat_ioctl_get_attributes(struct inode *inode, u32 __user *user_attr)
 {
+	u32 attr;
+
+	mutex_lock(&inode->i_mutex);
+	attr = fat_make_attrs(inode);
+	mutex_unlock(&inode->i_mutex);
+
+	return put_user(attr, user_attr);
+}
+
+static int fat_ioctl_set_attributes(struct file *file, u32 __user *user_attr)
+{
+	struct inode *inode = file_inode(file);
 	struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
-	u32 __user *user_attr = (u32 __user *)arg;
+	int is_dir = S_ISDIR(inode->i_mode);
+	u32 attr, oldattr;
+	struct iattr ia;
+	int err;
 
-	switch (cmd) {
-	case FAT_IOCTL_GET_ATTRIBUTES:
-	{
-		u32 attr;
+	err = get_user(attr, user_attr);
+	if (err)
+		goto out;
 
-		if (inode->i_ino == MSDOS_ROOT_INO)
-			attr = ATTR_DIR;
-		else
-			attr = fat_attr(inode);
+	err = mnt_want_write_file(file);
+	if (err)
+		goto out;
+	mutex_lock(&inode->i_mutex);
 
-		return put_user(attr, user_attr);
+	/*
+	 * ATTR_VOLUME and ATTR_DIR cannot be changed; this also
+	 * prevents the user from turning us into a VFAT
+	 * longname entry.  Also, we obviously can't set
+	 * any of the NTFS attributes in the high 24 bits.
+	 */
+	attr &= 0xff & ~(ATTR_VOLUME | ATTR_DIR);
+	/* Merge in ATTR_VOLUME and ATTR_DIR */
+	attr |= (MSDOS_I(inode)->i_attrs & ATTR_VOLUME) |
+		(is_dir ? ATTR_DIR : 0);
+	oldattr = fat_make_attrs(inode);
+
+	/* Equivalent to a chmod() */
+	ia.ia_valid = ATTR_MODE | ATTR_CTIME;
+	ia.ia_ctime = current_fs_time(inode->i_sb);
+	if (is_dir)
+		ia.ia_mode = fat_make_mode(sbi, attr, S_IRWXUGO);
+	else {
+		ia.ia_mode = fat_make_mode(sbi, attr,
+			S_IRUGO | S_IWUGO | (inode->i_mode & S_IXUGO));
 	}
-	case FAT_IOCTL_SET_ATTRIBUTES:
-	{
-		u32 attr, oldattr;
-		int err, is_dir = S_ISDIR(inode->i_mode);
-		struct iattr ia;
 
-		err = get_user(attr, user_attr);
-		if (err)
-			return err;
+	/* The root directory has no attributes */
+	if (inode->i_ino == MSDOS_ROOT_INO && attr != ATTR_DIR) {
+		err = -EINVAL;
+		goto out_unlock_inode;
+	}
 
-		mutex_lock(&inode->i_mutex);
+	if (sbi->options.sys_immutable &&
+	    ((attr | oldattr) & ATTR_SYS) &&
+	    !capable(CAP_LINUX_IMMUTABLE)) {
+		err = -EPERM;
+		goto out_unlock_inode;
+	}
 
-		if (IS_RDONLY(inode)) {
-			err = -EROFS;
-			goto up;
-		}
+	/*
+	 * The security check is questionable...  We single
+	 * out the RO attribute for checking by the security
+	 * module, just because it maps to a file mode.
+	 */
+	err = security_inode_setattr(file->f_path.dentry, &ia);
+	if (err)
+		goto out_unlock_inode;
 
-		/*
-		 * ATTR_VOLUME and ATTR_DIR cannot be changed; this also
-		 * prevents the user from turning us into a VFAT
-		 * longname entry.  Also, we obviously can't set
-		 * any of the NTFS attributes in the high 24 bits.
-		 */
-		attr &= 0xff & ~(ATTR_VOLUME | ATTR_DIR);
-		/* Merge in ATTR_VOLUME and ATTR_DIR */
-		attr |= (MSDOS_I(inode)->i_attrs & ATTR_VOLUME) |
-			(is_dir ? ATTR_DIR : 0);
-		oldattr = fat_attr(inode);
-
-		/* Equivalent to a chmod() */
-		ia.ia_valid = ATTR_MODE | ATTR_CTIME;
-		if (is_dir) {
-			ia.ia_mode = MSDOS_MKMODE(attr,
-				S_IRWXUGO & ~sbi->options.fs_dmask)
-				| S_IFDIR;
-		} else {
-			ia.ia_mode = MSDOS_MKMODE(attr,
-				(S_IRUGO | S_IWUGO | (inode->i_mode & S_IXUGO))
-				& ~sbi->options.fs_fmask)
-				| S_IFREG;
-		}
+	/* This MUST be done before doing anything irreversible... */
+	err = fat_setattr(file->f_path.dentry, &ia);
+	if (err)
+		goto out_unlock_inode;
 
-		/* The root directory has no attributes */
-		if (inode->i_ino == MSDOS_ROOT_INO && attr != ATTR_DIR) {
-			err = -EINVAL;
-			goto up;
-		}
+	fsnotify_change(file->f_path.dentry, ia.ia_valid);
+	if (sbi->options.sys_immutable) {
+		if (attr & ATTR_SYS)
+			inode->i_flags |= S_IMMUTABLE;
+		else
+			inode->i_flags &= ~S_IMMUTABLE;
+	}
 
-		if (sbi->options.sys_immutable) {
-			if ((attr | oldattr) & ATTR_SYS) {
-				if (!capable(CAP_LINUX_IMMUTABLE)) {
-					err = -EPERM;
-					goto up;
-				}
-			}
-		}
+	fat_save_attrs(inode, attr);
+	mark_inode_dirty(inode);
+out_unlock_inode:
+	mutex_unlock(&inode->i_mutex);
+	mnt_drop_write_file(file);
+out:
+	return err;
+}
 
-		/* This MUST be done before doing anything irreversible... */
-		err = notify_change(filp->f_path.dentry, &ia);
-		if (err)
-			goto up;
+static int fat_ioctl_get_volume_id(struct inode *inode, u32 __user *user_attr)
+{
+	struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
+	return put_user(sbi->vol_id, user_attr);
+}
 
-		if (sbi->options.sys_immutable) {
-			if (attr & ATTR_SYS)
-				inode->i_flags |= S_IMMUTABLE;
-			else
-				inode->i_flags &= S_IMMUTABLE;
-		}
+long fat_generic_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
+{
+	struct inode *inode = file_inode(filp);
+	u32 __user *user_attr = (u32 __user *)arg;
 
-		MSDOS_I(inode)->i_attrs = attr & ATTR_UNUSED;
-		mark_inode_dirty(inode);
-	up:
-		mutex_unlock(&inode->i_mutex);
-		return err;
-	}
+	switch (cmd) {
+	case FAT_IOCTL_GET_ATTRIBUTES:
+		return fat_ioctl_get_attributes(inode, user_attr);
+	case FAT_IOCTL_SET_ATTRIBUTES:
+		return fat_ioctl_set_attributes(filp, user_attr);
+	case FAT_IOCTL_GET_VOLUME_ID:
+		return fat_ioctl_get_volume_id(inode, user_attr);
 	default:
 		return -ENOTTY;	/* Inappropriate ioctl for device */
 	}
 }
 
+#ifdef CONFIG_COMPAT
+static long fat_generic_compat_ioctl(struct file *filp, unsigned int cmd,
+				      unsigned long arg)
+
+{
+	return fat_generic_ioctl(filp, cmd, (unsigned long)compat_ptr(arg));
+}
+#endif
+
 static int fat_file_release(struct inode *inode, struct file *filp)
 {
 	if ((filp->f_mode & FMODE_WRITE) &&
 	     MSDOS_SB(inode->i_sb)->options.flush) {
 		fat_flush_inodes(inode->i_sb, inode, NULL);
-		congestion_wait(WRITE, HZ/10);
+		congestion_wait(BLK_RW_ASYNC, HZ/10);
 	}
 	return 0;
 }
 
+int fat_file_fsync(struct file *filp, loff_t start, loff_t end, int datasync)
+{
+	struct inode *inode = filp->f_mapping->host;
+	int res, err;
+
+	res = generic_file_fsync(filp, start, end, datasync);
+	err = sync_mapping_buffers(MSDOS_SB(inode->i_sb)->fat_inode->i_mapping);
+
+	return res ? res : err;
+}
+
+
 const struct file_operations fat_file_operations = {
 	.llseek		= generic_file_llseek,
-	.read		= do_sync_read,
-	.write		= do_sync_write,
-	.aio_read	= generic_file_aio_read,
-	.aio_write	= generic_file_aio_write,
+	.read		= new_sync_read,
+	.write		= new_sync_write,
+	.read_iter	= generic_file_read_iter,
+	.write_iter	= generic_file_write_iter,
 	.mmap		= generic_file_mmap,
 	.release	= fat_file_release,
-	.ioctl		= fat_generic_ioctl,
-	.fsync		= file_fsync,
+	.unlocked_ioctl	= fat_generic_ioctl,
+#ifdef CONFIG_COMPAT
+	.compat_ioctl	= fat_generic_compat_ioctl,
+#endif
+	.fsync		= fat_file_fsync,
 	.splice_read	= generic_file_splice_read,
 };
 
@@ -149,110 +196,30 @@ static int fat_cont_expand(struct inode *inode, loff_t size)
 
 	inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC;
 	mark_inode_dirty(inode);
-	if (IS_SYNC(inode))
-		err = sync_page_range_nolock(inode, mapping, start, count);
-out:
-	return err;
-}
-
-static int check_mode(const struct msdos_sb_info *sbi, mode_t mode)
-{
-	mode_t req = mode & ~S_IFMT;
-
-	/*
-	 * Of the r and x bits, all (subject to umask) must be present. Of the
-	 * w bits, either all (subject to umask) or none must be present.
-	 */
-
-	if (S_ISREG(mode)) {
-		req &= ~sbi->options.fs_fmask;
-
-		if ((req & (S_IRUGO | S_IXUGO)) !=
-		    ((S_IRUGO | S_IXUGO) & ~sbi->options.fs_fmask))
-			return -EPERM;
-
-		if ((req & S_IWUGO) != 0 &&
-		    (req & S_IWUGO) != (S_IWUGO & ~sbi->options.fs_fmask))
-			return -EPERM;
-	} else if (S_ISDIR(mode)) {
-		req &= ~sbi->options.fs_dmask;
-
-		if ((req & (S_IRUGO | S_IXUGO)) !=
-		    ((S_IRUGO | S_IXUGO) & ~sbi->options.fs_dmask))
-			return -EPERM;
-
-		if ((req & S_IWUGO) != 0 &&
-		    (req & S_IWUGO) != (S_IWUGO & ~sbi->options.fs_dmask))
-			return -EPERM;
-	} else {
-		return -EPERM;
-	}
+	if (IS_SYNC(inode)) {
+		int err2;
 
-	return 0;
-}
-
-int fat_notify_change(struct dentry *dentry, struct iattr *attr)
-{
-	struct msdos_sb_info *sbi = MSDOS_SB(dentry->d_sb);
-	struct inode *inode = dentry->d_inode;
-	int mask, error = 0;
-
-	lock_kernel();
-
-	/*
-	 * Expand the file. Since inode_setattr() updates ->i_size
-	 * before calling the ->truncate(), but FAT needs to fill the
-	 * hole before it.
-	 */
-	if (attr->ia_valid & ATTR_SIZE) {
-		if (attr->ia_size > inode->i_size) {
-			error = fat_cont_expand(inode, attr->ia_size);
-			if (error || attr->ia_valid == ATTR_SIZE)
-				goto out;
-			attr->ia_valid &= ~ATTR_SIZE;
+		/*
+		 * Opencode syncing since we don't have a file open to use
+		 * standard fsync path.
+		 */
+		err = filemap_fdatawrite_range(mapping, start,
+					       start + count - 1);
+		err2 = sync_mapping_buffers(mapping);
+		if (!err)
+			err = err2;
+		err2 = write_inode_now(inode, 1);
+		if (!err)
+			err = err2;
+		if (!err) {
+			err =  filemap_fdatawait_range(mapping, start,
+						       start + count - 1);
 		}
 	}
-
-	error = inode_change_ok(inode, attr);
-	if (error) {
-		if (sbi->options.quiet)
-			error = 0;
-		goto out;
-	}
-	if (((attr->ia_valid & ATTR_UID) &&
-	     (attr->ia_uid != sbi->options.fs_uid)) ||
-	    ((attr->ia_valid & ATTR_GID) &&
-	     (attr->ia_gid != sbi->options.fs_gid)))
-		error = -EPERM;
-
-	if (error) {
-		if (sbi->options.quiet)
-			error = 0;
-		goto out;
-	}
-
-	if (attr->ia_valid & ATTR_MODE) {
-		error = check_mode(sbi, attr->ia_mode);
-		if (error != 0 && !sbi->options.quiet)
-			goto out;
-	}
-
-	error = inode_setattr(inode, attr);
-	if (error)
-		goto out;
-
-	if (S_ISDIR(inode->i_mode))
-		mask = sbi->options.fs_dmask;
-	else
-		mask = sbi->options.fs_fmask;
-	inode->i_mode &= S_IFMT | (S_IRWXUGO & ~mask);
 out:
-	unlock_kernel();
-	return error;
+	return err;
 }
 
-EXPORT_SYMBOL_GPL(fat_notify_change);
-
 /* Free all clusters after the skip'th cluster. */
 static int fat_free(struct inode *inode, int skip)
 {
@@ -302,9 +269,9 @@ static int fat_free(struct inode *inode, int skip)
 			fatent_brelse(&fatent);
 			return 0;
 		} else if (ret == FAT_ENT_FREE) {
-			fat_fs_panic(sb,
+			fat_fs_error(sb,
 				     "%s: invalid cluster chain (i_pos %lld)",
-				     __FUNCTION__, MSDOS_I(inode)->i_pos);
+				     __func__, MSDOS_I(inode)->i_pos);
 			ret = -EIO;
 		} else if (ret > 0) {
 			err = fat_ent_write(inode, &fatent, FAT_ENT_EOF, wait);
@@ -323,7 +290,7 @@ static int fat_free(struct inode *inode, int skip)
 	return fat_free_clusters(inode, free_start);
 }
 
-void fat_truncate(struct inode *inode)
+void fat_truncate_blocks(struct inode *inode, loff_t offset)
 {
 	struct msdos_sb_info *sbi = MSDOS_SB(inode->i_sb);
 	const unsigned int cluster_size = sbi->cluster_size;
@@ -333,14 +300,12 @@ void fat_truncate(struct inode *inode)
 	 * This protects against truncating a file bigger than it was then
 	 * trying to write into the hole.
 	 */
-	if (MSDOS_I(inode)->mmu_private > inode->i_size)
-		MSDOS_I(inode)->mmu_private = inode->i_size;
+	if (MSDOS_I(inode)->mmu_private > offset)
+		MSDOS_I(inode)->mmu_private = offset;
 
-	nr_clusters = (inode->i_size + (cluster_size - 1)) >> sbi->cluster_bits;
+	nr_clusters = (offset + (cluster_size - 1)) >> sbi->cluster_bits;
 
-	lock_kernel();
 	fat_free(inode, nr_clusters);
-	unlock_kernel();
 	fat_flush_inodes(inode->i_sb, inode, NULL);
 }
 
@@ -349,12 +314,149 @@ int fat_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
 	struct inode *inode = dentry->d_inode;
 	generic_fillattr(inode, stat);
 	stat->blksize = MSDOS_SB(inode->i_sb)->cluster_size;
+
+	if (MSDOS_SB(inode->i_sb)->options.nfs == FAT_NFS_NOSTALE_RO) {
+		/* Use i_pos for ino. This is used as fileid of nfs. */
+		stat->ino = fat_i_pos_read(MSDOS_SB(inode->i_sb), inode);
+	}
 	return 0;
 }
 EXPORT_SYMBOL_GPL(fat_getattr);
 
+static int fat_sanitize_mode(const struct msdos_sb_info *sbi,
+			     struct inode *inode, umode_t *mode_ptr)
+{
+	umode_t mask, perm;
+
+	/*
+	 * Note, the basic check is already done by a caller of
+	 * (attr->ia_mode & ~FAT_VALID_MODE)
+	 */
+
+	if (S_ISREG(inode->i_mode))
+		mask = sbi->options.fs_fmask;
+	else
+		mask = sbi->options.fs_dmask;
+
+	perm = *mode_ptr & ~(S_IFMT | mask);
+
+	/*
+	 * Of the r and x bits, all (subject to umask) must be present. Of the
+	 * w bits, either all (subject to umask) or none must be present.
+	 *
+	 * If fat_mode_can_hold_ro(inode) is false, can't change w bits.
+	 */
+	if ((perm & (S_IRUGO | S_IXUGO)) != (inode->i_mode & (S_IRUGO|S_IXUGO)))
+		return -EPERM;
+	if (fat_mode_can_hold_ro(inode)) {
+		if ((perm & S_IWUGO) && ((perm & S_IWUGO) != (S_IWUGO & ~mask)))
+			return -EPERM;
+	} else {
+		if ((perm & S_IWUGO) != (S_IWUGO & ~mask))
+			return -EPERM;
+	}
+
+	*mode_ptr &= S_IFMT | perm;
+
+	return 0;
+}
+
+static int fat_allow_set_time(struct msdos_sb_info *sbi, struct inode *inode)
+{
+	umode_t allow_utime = sbi->options.allow_utime;
+
+	if (!uid_eq(current_fsuid(), inode->i_uid)) {
+		if (in_group_p(inode->i_gid))
+			allow_utime >>= 3;
+		if (allow_utime & MAY_WRITE)
+			return 1;
+	}
+
+	/* use a default check */
+	return 0;
+}
+
+#define TIMES_SET_FLAGS	(ATTR_MTIME_SET | ATTR_ATIME_SET | ATTR_TIMES_SET)
+/* valid file mode bits */
+#define FAT_VALID_MODE	(S_IFREG | S_IFDIR | S_IRWXUGO)
+
+int fat_setattr(struct dentry *dentry, struct iattr *attr)
+{
+	struct msdos_sb_info *sbi = MSDOS_SB(dentry->d_sb);
+	struct inode *inode = dentry->d_inode;
+	unsigned int ia_valid;
+	int error;
+
+	/* Check for setting the inode time. */
+	ia_valid = attr->ia_valid;
+	if (ia_valid & TIMES_SET_FLAGS) {
+		if (fat_allow_set_time(sbi, inode))
+			attr->ia_valid &= ~TIMES_SET_FLAGS;
+	}
+
+	error = inode_change_ok(inode, attr);
+	attr->ia_valid = ia_valid;
+	if (error) {
+		if (sbi->options.quiet)
+			error = 0;
+		goto out;
+	}
+
+	/*
+	 * Expand the file. Since inode_setattr() updates ->i_size
+	 * before calling the ->truncate(), but FAT needs to fill the
+	 * hole before it. XXX: this is no longer true with new truncate
+	 * sequence.
+	 */
+	if (attr->ia_valid & ATTR_SIZE) {
+		inode_dio_wait(inode);
+
+		if (attr->ia_size > inode->i_size) {
+			error = fat_cont_expand(inode, attr->ia_size);
+			if (error || attr->ia_valid == ATTR_SIZE)
+				goto out;
+			attr->ia_valid &= ~ATTR_SIZE;
+		}
+	}
+
+	if (((attr->ia_valid & ATTR_UID) &&
+	     (!uid_eq(attr->ia_uid, sbi->options.fs_uid))) ||
+	    ((attr->ia_valid & ATTR_GID) &&
+	     (!gid_eq(attr->ia_gid, sbi->options.fs_gid))) ||
+	    ((attr->ia_valid & ATTR_MODE) &&
+	     (attr->ia_mode & ~FAT_VALID_MODE)))
+		error = -EPERM;
+
+	if (error) {
+		if (sbi->options.quiet)
+			error = 0;
+		goto out;
+	}
+
+	/*
+	 * We don't return -EPERM here. Yes, strange, but this is too
+	 * old behavior.
+	 */
+	if (attr->ia_valid & ATTR_MODE) {
+		if (fat_sanitize_mode(sbi, inode, &attr->ia_mode) < 0)
+			attr->ia_valid &= ~ATTR_MODE;
+	}
+
+	if (attr->ia_valid & ATTR_SIZE) {
+		down_write(&MSDOS_I(inode)->truncate_lock);
+		truncate_setsize(inode, attr->ia_size);
+		fat_truncate_blocks(inode, attr->ia_size);
+		up_write(&MSDOS_I(inode)->truncate_lock);
+	}
+
+	setattr_copy(inode, attr);
+	mark_inode_dirty(inode);
+out:
+	return error;
+}
+EXPORT_SYMBOL_GPL(fat_setattr);
+
 const struct inode_operations fat_file_inode_operations = {
-	.truncate	= fat_truncate,
-	.setattr	= fat_notify_change,
+	.setattr	= fat_setattr,
 	.getattr	= fat_getattr,
 };