1 files changed, 202 insertions, 156 deletions

diff --git a/fs/cramfs/inode.c b/fs/cramfs/inode.c
index 7fe85415ae7..ddcfe590b8a 100644
--- a/fs/cramfs/inode.c
+++ b/fs/cramfs/inode.c
@@ -17,99 +17,113 @@
 #include <linux/init.h>
 #include <linux/string.h>
 #include <linux/blkdev.h>
-#include <linux/cramfs_fs.h>
 #include <linux/slab.h>
-#include <linux/cramfs_fs_sb.h>
-#include <linux/buffer_head.h>
 #include <linux/vfs.h>
-#include <asm/semaphore.h>
-
+#include <linux/mutex.h>
+#include <uapi/linux/cramfs_fs.h>
 #include <asm/uaccess.h>
 
-static struct super_operations cramfs_ops;
-static struct inode_operations cramfs_dir_inode_operations;
-static struct file_operations cramfs_directory_operations;
-static struct address_space_operations cramfs_aops;
-
-static DECLARE_MUTEX(read_mutex);
-
-
-/* These two macros may change in future, to provide better st_ino
-   semantics. */
-#define CRAMINO(x)	((x)->offset?(x)->offset<<2:1)
-#define OFFSET(x)	((x)->i_ino)
+#include "internal.h"
 
+/*
+ * cramfs super-block data in memory
+ */
+struct cramfs_sb_info {
+	unsigned long magic;
+	unsigned long size;
+	unsigned long blocks;
+	unsigned long files;
+	unsigned long flags;
+};
 
-static int cramfs_iget5_test(struct inode *inode, void *opaque)
+static inline struct cramfs_sb_info *CRAMFS_SB(struct super_block *sb)
 {
-	struct cramfs_inode *cramfs_inode = opaque;
-
-	if (inode->i_ino != CRAMINO(cramfs_inode))
-		return 0; /* does not match */
-
-	if (inode->i_ino != 1)
-		return 1;
+	return sb->s_fs_info;
+}
 
-	/* all empty directories, char, block, pipe, and sock, share inode #1 */
+static const struct super_operations cramfs_ops;
+static const struct inode_operations cramfs_dir_inode_operations;
+static const struct file_operations cramfs_directory_operations;
+static const struct address_space_operations cramfs_aops;
 
-	if ((inode->i_mode != cramfs_inode->mode) ||
-	    (inode->i_gid != cramfs_inode->gid) ||
-	    (inode->i_uid != cramfs_inode->uid))
-		return 0; /* does not match */
+static DEFINE_MUTEX(read_mutex);
 
-	if ((S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) &&
-	    (inode->i_rdev != old_decode_dev(cramfs_inode->size)))
-		return 0; /* does not match */
 
-	return 1; /* matches */
-}
+/* These macros may change in future, to provide better st_ino semantics. */
+#define OFFSET(x)	((x)->i_ino)
 
-static int cramfs_iget5_set(struct inode *inode, void *opaque)
+static unsigned long cramino(const struct cramfs_inode *cino, unsigned int offset)
 {
-	struct cramfs_inode *cramfs_inode = opaque;
-	inode->i_ino = CRAMINO(cramfs_inode);
-	return 0;
+	if (!cino->offset)
+		return offset + 1;
+	if (!cino->size)
+		return offset + 1;
+
+	/*
+	 * The file mode test fixes buggy mkcramfs implementations where
+	 * cramfs_inode->offset is set to a non zero value for entries
+	 * which did not contain data, like devices node and fifos.
+	 */
+	switch (cino->mode & S_IFMT) {
+	case S_IFREG:
+	case S_IFDIR:
+	case S_IFLNK:
+		return cino->offset << 2;
+	default:
+		break;
+	}
+	return offset + 1;
 }
 
 static struct inode *get_cramfs_inode(struct super_block *sb,
-				struct cramfs_inode * cramfs_inode)
+	const struct cramfs_inode *cramfs_inode, unsigned int offset)
 {
-	struct inode *inode = iget5_locked(sb, CRAMINO(cramfs_inode),
-					    cramfs_iget5_test, cramfs_iget5_set,
-					    cramfs_inode);
+	struct inode *inode;
 	static struct timespec zerotime;
 
-	if (inode && (inode->i_state & I_NEW)) {
-		inode->i_mode = cramfs_inode->mode;
-		inode->i_uid = cramfs_inode->uid;
+	inode = iget_locked(sb, cramino(cramfs_inode, offset));
+	if (!inode)
+		return ERR_PTR(-ENOMEM);
+	if (!(inode->i_state & I_NEW))
+		return inode;
+
+	switch (cramfs_inode->mode & S_IFMT) {
+	case S_IFREG:
+		inode->i_fop = &generic_ro_fops;
+		inode->i_data.a_ops = &cramfs_aops;
+		break;
+	case S_IFDIR:
+		inode->i_op = &cramfs_dir_inode_operations;
+		inode->i_fop = &cramfs_directory_operations;
+		break;
+	case S_IFLNK:
+		inode->i_op = &page_symlink_inode_operations;
+		inode->i_data.a_ops = &cramfs_aops;
+		break;
+	default:
+		init_special_inode(inode, cramfs_inode->mode,
+				old_decode_dev(cramfs_inode->size));
+	}
+
+	inode->i_mode = cramfs_inode->mode;
+	i_uid_write(inode, cramfs_inode->uid);
+	i_gid_write(inode, cramfs_inode->gid);
+
+	/* if the lower 2 bits are zero, the inode contains data */
+	if (!(inode->i_ino & 3)) {
 		inode->i_size = cramfs_inode->size;
 		inode->i_blocks = (cramfs_inode->size - 1) / 512 + 1;
-		inode->i_blksize = PAGE_CACHE_SIZE;
-		inode->i_gid = cramfs_inode->gid;
-		/* Struct copy intentional */
-		inode->i_mtime = inode->i_atime = inode->i_ctime = zerotime;
-		inode->i_ino = CRAMINO(cramfs_inode);
-		/* inode->i_nlink is left 1 - arguably wrong for directories,
-		   but it's the best we can do without reading the directory
-	           contents.  1 yields the right result in GNU find, even
-		   without -noleaf option. */
-		if (S_ISREG(inode->i_mode)) {
-			inode->i_fop = &generic_ro_fops;
-			inode->i_data.a_ops = &cramfs_aops;
-		} else if (S_ISDIR(inode->i_mode)) {
-			inode->i_op = &cramfs_dir_inode_operations;
-			inode->i_fop = &cramfs_directory_operations;
-		} else if (S_ISLNK(inode->i_mode)) {
-			inode->i_op = &page_symlink_inode_operations;
-			inode->i_data.a_ops = &cramfs_aops;
-		} else {
-			inode->i_size = 0;
-			inode->i_blocks = 0;
-			init_special_inode(inode, inode->i_mode,
-				old_decode_dev(cramfs_inode->size));
-		}
-		unlock_new_inode(inode);
 	}
+
+	/* Struct copy intentional */
+	inode->i_mtime = inode->i_atime = inode->i_ctime = zerotime;
+	/* inode->i_nlink is left 1 - arguably wrong for directories,
+	   but it's the best we can do without reading the directory
+	   contents.  1 yields the right result in GNU find, even
+	   without -noleaf option. */
+
+	unlock_new_inode(inode);
+
 	return inode;
 }
 
@@ -150,7 +164,7 @@ static void *cramfs_read(struct super_block *sb, unsigned int offset, unsigned i
 {
 	struct address_space *mapping = sb->s_bdev->bd_inode->i_mapping;
 	struct page *pages[BLKS_PER_BUF];
-	unsigned i, blocknr, buffer, unread;
+	unsigned i, blocknr, buffer;
 	unsigned long devsize;
 	char *data;
 
@@ -177,14 +191,11 @@ static void *cramfs_read(struct super_block *sb, unsigned int offset, unsigned i
 	devsize = mapping->host->i_size >> PAGE_CACHE_SHIFT;
 
 	/* Ok, read in BLKS_PER_BUF pages completely first. */
-	unread = 0;
 	for (i = 0; i < BLKS_PER_BUF; i++) {
 		struct page *page = NULL;
 
 		if (blocknr + i < devsize) {
-			page = read_cache_page(mapping, blocknr + i,
-				(filler_t *)mapping->a_ops->readpage,
-				NULL);
+			page = read_mapping_page(mapping, blocknr + i, NULL);
 			/* synchronous error? */
 			if (IS_ERR(page))
 				page = NULL;
@@ -223,14 +234,16 @@ static void *cramfs_read(struct super_block *sb, unsigned int offset, unsigned i
 	return read_buffers[buffer] + offset;
 }
 
-static void cramfs_put_super(struct super_block *sb)
+static void cramfs_kill_sb(struct super_block *sb)
 {
-	kfree(sb->s_fs_info);
-	sb->s_fs_info = NULL;
+	struct cramfs_sb_info *sbi = CRAMFS_SB(sb);
+	kill_block_super(sb);
+	kfree(sbi);
 }
 
 static int cramfs_remount(struct super_block *sb, int *flags, char *data)
 {
+	sync_filesystem(sb);
 	*flags |= MS_RDONLY;
 	return 0;
 }
@@ -245,45 +258,56 @@ static int cramfs_fill_super(struct super_block *sb, void *data, int silent)
 
 	sb->s_flags |= MS_RDONLY;
 
-	sbi = kmalloc(sizeof(struct cramfs_sb_info), GFP_KERNEL);
+	sbi = kzalloc(sizeof(struct cramfs_sb_info), GFP_KERNEL);
 	if (!sbi)
 		return -ENOMEM;
 	sb->s_fs_info = sbi;
-	memset(sbi, 0, sizeof(struct cramfs_sb_info));
 
 	/* Invalidate the read buffers on mount: think disk change.. */
-	down(&read_mutex);
+	mutex_lock(&read_mutex);
 	for (i = 0; i < READ_BUFFERS; i++)
 		buffer_blocknr[i] = -1;
 
 	/* Read the first block and get the superblock from it */
 	memcpy(&super, cramfs_read(sb, 0, sizeof(super)), sizeof(super));
-	up(&read_mutex);
+	mutex_unlock(&read_mutex);
 
 	/* Do sanity checks on the superblock */
 	if (super.magic != CRAMFS_MAGIC) {
+		/* check for wrong endianness */
+		if (super.magic == CRAMFS_MAGIC_WEND) {
+			if (!silent)
+				printk(KERN_ERR "cramfs: wrong endianness\n");
+			return -EINVAL;
+		}
+
 		/* check at 512 byte offset */
-		down(&read_mutex);
+		mutex_lock(&read_mutex);
 		memcpy(&super, cramfs_read(sb, 512, sizeof(super)), sizeof(super));
-		up(&read_mutex);
+		mutex_unlock(&read_mutex);
 		if (super.magic != CRAMFS_MAGIC) {
-			if (!silent)
+			if (super.magic == CRAMFS_MAGIC_WEND && !silent)
+				printk(KERN_ERR "cramfs: wrong endianness\n");
+			else if (!silent)
 				printk(KERN_ERR "cramfs: wrong magic\n");
-			goto out;
+			return -EINVAL;
 		}
 	}
 
 	/* get feature flags first */
 	if (super.flags & ~CRAMFS_SUPPORTED_FLAGS) {
 		printk(KERN_ERR "cramfs: unsupported filesystem features\n");
-		goto out;
+		return -EINVAL;
 	}
 
 	/* Check that the root inode is in a sane state */
 	if (!S_ISDIR(super.root.mode)) {
 		printk(KERN_ERR "cramfs: root is not a directory\n");
-		goto out;
+		return -EINVAL;
 	}
+	/* correct strange, hard-coded permissions of mkcramfs */
+	super.root.mode |= (S_IRUSR | S_IXUSR | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH);
+
 	root_offset = super.root.offset << 2;
 	if (super.flags & CRAMFS_FLAG_FSID_VERSION_2) {
 		sbi->size=super.size;
@@ -303,28 +327,25 @@ static int cramfs_fill_super(struct super_block *sb, void *data, int silent)
 		  (root_offset != 512 + sizeof(struct cramfs_super))))
 	{
 		printk(KERN_ERR "cramfs: bad root offset %lu\n", root_offset);
-		goto out;
+		return -EINVAL;
 	}
 
 	/* Set it all up.. */
 	sb->s_op = &cramfs_ops;
-	root = get_cramfs_inode(sb, &super.root);
-	if (!root)
-		goto out;
-	sb->s_root = d_alloc_root(root);
-	if (!sb->s_root) {
-		iput(root);
-		goto out;
-	}
+	root = get_cramfs_inode(sb, &super.root, 0);
+	if (IS_ERR(root))
+		return PTR_ERR(root);
+	sb->s_root = d_make_root(root);
+	if (!sb->s_root)
+		return -ENOMEM;
 	return 0;
-out:
-	kfree(sbi);
-	sb->s_fs_info = NULL;
-	return -EINVAL;
 }
 
-static int cramfs_statfs(struct super_block *sb, struct kstatfs *buf)
+static int cramfs_statfs(struct dentry *dentry, struct kstatfs *buf)
 {
+	struct super_block *sb = dentry->d_sb;
+	u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
+
 	buf->f_type = CRAMFS_MAGIC;
 	buf->f_bsize = PAGE_CACHE_SIZE;
 	buf->f_blocks = CRAMFS_SB(sb)->blocks;
@@ -332,6 +353,8 @@ static int cramfs_statfs(struct super_block *sb, struct kstatfs *buf)
 	buf->f_bavail = 0;
 	buf->f_files = CRAMFS_SB(sb)->files;
 	buf->f_ffree = 0;
+	buf->f_fsid.val[0] = (u32)id;
+	buf->f_fsid.val[1] = (u32)(id >> 32);
 	buf->f_namelen = CRAMFS_MAXPATHLEN;
 	return 0;
 }
@@ -339,37 +362,35 @@ static int cramfs_statfs(struct super_block *sb, struct kstatfs *buf)
 /*
  * Read a cramfs directory entry.
  */
-static int cramfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
+static int cramfs_readdir(struct file *file, struct dir_context *ctx)
 {
-	struct inode *inode = filp->f_dentry->d_inode;
+	struct inode *inode = file_inode(file);
 	struct super_block *sb = inode->i_sb;
 	char *buf;
 	unsigned int offset;
-	int copied;
 
 	/* Offset within the thing. */
-	offset = filp->f_pos;
-	if (offset >= inode->i_size)
+	if (ctx->pos >= inode->i_size)
 		return 0;
+	offset = ctx->pos;
 	/* Directory entries are always 4-byte aligned */
 	if (offset & 3)
 		return -EINVAL;
 
-	buf = kmalloc(256, GFP_KERNEL);
+	buf = kmalloc(CRAMFS_MAXPATHLEN, GFP_KERNEL);
 	if (!buf)
 		return -ENOMEM;
 
-	copied = 0;
 	while (offset < inode->i_size) {
 		struct cramfs_inode *de;
 		unsigned long nextoffset;
 		char *name;
 		ino_t ino;
-		mode_t mode;
-		int namelen, error;
+		umode_t mode;
+		int namelen;
 
-		down(&read_mutex);
-		de = cramfs_read(sb, OFFSET(inode) + offset, sizeof(*de)+256);
+		mutex_lock(&read_mutex);
+		de = cramfs_read(sb, OFFSET(inode) + offset, sizeof(*de)+CRAMFS_MAXPATHLEN);
 		name = (char *)(de+1);
 
 		/*
@@ -379,9 +400,9 @@ static int cramfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
 		 */
 		namelen = de->namelen << 2;
 		memcpy(buf, name, namelen);
-		ino = CRAMINO(de);
+		ino = cramino(de, OFFSET(inode) + offset);
 		mode = de->mode;
-		up(&read_mutex);
+		mutex_unlock(&read_mutex);
 		nextoffset = offset + sizeof(*de) + namelen;
 		for (;;) {
 			if (!namelen) {
@@ -392,13 +413,10 @@ static int cramfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
 				break;
 			namelen--;
 		}
-		error = filldir(dirent, buf, namelen, offset, ino, mode >> 12);
-		if (error)
+		if (!dir_emit(ctx, buf, namelen, ino, mode >> 12))
 			break;
 
-		offset = nextoffset;
-		filp->f_pos = offset;
-		copied++;
+		ctx->pos = offset = nextoffset;
 	}
 	kfree(buf);
 	return 0;
@@ -407,19 +425,21 @@ static int cramfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
 /*
  * Lookup and fill in the inode data..
  */
-static struct dentry * cramfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
+static struct dentry * cramfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
 {
 	unsigned int offset = 0;
+	struct inode *inode = NULL;
 	int sorted;
 
-	down(&read_mutex);
+	mutex_lock(&read_mutex);
 	sorted = CRAMFS_SB(dir->i_sb)->flags & CRAMFS_FLAG_SORTED_DIRS;
 	while (offset < dir->i_size) {
 		struct cramfs_inode *de;
 		char *name;
 		int namelen, retval;
+		int dir_off = OFFSET(dir) + offset;
 
-		de = cramfs_read(dir->i_sb, OFFSET(dir) + offset, sizeof(*de)+256);
+		de = cramfs_read(dir->i_sb, dir_off, sizeof(*de)+CRAMFS_MAXPATHLEN);
 		name = (char *)(de+1);
 
 		/* Try to take advantage of sorted directories */
@@ -435,8 +455,8 @@ static struct dentry * cramfs_lookup(struct inode *dir, struct dentry *dentry, s
 
 		for (;;) {
 			if (!namelen) {
-				up(&read_mutex);
-				return ERR_PTR(-EIO);
+				inode = ERR_PTR(-EIO);
+				goto out;
 			}
 			if (name[namelen-1])
 				break;
@@ -448,61 +468,80 @@ static struct dentry * cramfs_lookup(struct inode *dir, struct dentry *dentry, s
 		if (retval > 0)
 			continue;
 		if (!retval) {
-			struct cramfs_inode entry = *de;
-			up(&read_mutex);
-			d_add(dentry, get_cramfs_inode(dir->i_sb, &entry));
-			return NULL;
+			inode = get_cramfs_inode(dir->i_sb, de, dir_off);
+			break;
 		}
 		/* else (retval < 0) */
 		if (sorted)
 			break;
 	}
-	up(&read_mutex);
-	d_add(dentry, NULL);
+out:
+	mutex_unlock(&read_mutex);
+	if (IS_ERR(inode))
+		return ERR_CAST(inode);
+	d_add(dentry, inode);
 	return NULL;
 }
 
 static int cramfs_readpage(struct file *file, struct page * page)
 {
 	struct inode *inode = page->mapping->host;
-	u32 maxblock, bytes_filled;
+	u32 maxblock;
+	int bytes_filled;
 	void *pgdata;
 
 	maxblock = (inode->i_size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
 	bytes_filled = 0;
+	pgdata = kmap(page);
+
 	if (page->index < maxblock) {
 		struct super_block *sb = inode->i_sb;
 		u32 blkptr_offset = OFFSET(inode) + page->index*4;
 		u32 start_offset, compr_len;
 
 		start_offset = OFFSET(inode) + maxblock*4;
-		down(&read_mutex);
+		mutex_lock(&read_mutex);
 		if (page->index)
-			start_offset = *(u32 *) cramfs_read(sb, blkptr_offset-4, 4);
-		compr_len = (*(u32 *) cramfs_read(sb, blkptr_offset, 4) - start_offset);
-		up(&read_mutex);
-		pgdata = kmap(page);
+			start_offset = *(u32 *) cramfs_read(sb, blkptr_offset-4,
+				4);
+		compr_len = (*(u32 *) cramfs_read(sb, blkptr_offset, 4) -
+			start_offset);
+		mutex_unlock(&read_mutex);
+
 		if (compr_len == 0)
 			; /* hole */
-		else {
-			down(&read_mutex);
+		else if (unlikely(compr_len > (PAGE_CACHE_SIZE << 1))) {
+			pr_err("cramfs: bad compressed blocksize %u\n",
+				compr_len);
+			goto err;
+		} else {
+			mutex_lock(&read_mutex);
 			bytes_filled = cramfs_uncompress_block(pgdata,
 				 PAGE_CACHE_SIZE,
 				 cramfs_read(sb, start_offset, compr_len),
 				 compr_len);
-			up(&read_mutex);
+			mutex_unlock(&read_mutex);
+			if (unlikely(bytes_filled < 0))
+				goto err;
 		}
-	} else
-		pgdata = kmap(page);
+	}
+
 	memset(pgdata + bytes_filled, 0, PAGE_CACHE_SIZE - bytes_filled);
-	kunmap(page);
 	flush_dcache_page(page);
+	kunmap(page);
 	SetPageUptodate(page);
 	unlock_page(page);
 	return 0;
+
+err:
+	kunmap(page);
+	ClearPageUptodate(page);
+	SetPageError(page);
+	unlock_page(page);
+	return 0;
 }
 
-static struct address_space_operations cramfs_aops = {
+static const struct address_space_operations cramfs_aops = {
 	.readpage = cramfs_readpage
 };
 
@@ -513,40 +552,47 @@ static struct address_space_operations cramfs_aops = {
 /*
  * A directory can only readdir
  */
-static struct file_operations cramfs_directory_operations = {
+static const struct file_operations cramfs_directory_operations = {
 	.llseek		= generic_file_llseek,
 	.read		= generic_read_dir,
-	.readdir	= cramfs_readdir,
+	.iterate	= cramfs_readdir,
 };
 
-static struct inode_operations cramfs_dir_inode_operations = {
+static const struct inode_operations cramfs_dir_inode_operations = {
 	.lookup		= cramfs_lookup,
 };
 
-static struct super_operations cramfs_ops = {
-	.put_super	= cramfs_put_super,
+static const struct super_operations cramfs_ops = {
 	.remount_fs	= cramfs_remount,
 	.statfs		= cramfs_statfs,
 };
 
-static struct super_block *cramfs_get_sb(struct file_system_type *fs_type,
+static struct dentry *cramfs_mount(struct file_system_type *fs_type,
 	int flags, const char *dev_name, void *data)
 {
-	return get_sb_bdev(fs_type, flags, dev_name, data, cramfs_fill_super);
+	return mount_bdev(fs_type, flags, dev_name, data, cramfs_fill_super);
 }
 
 static struct file_system_type cramfs_fs_type = {
 	.owner		= THIS_MODULE,
 	.name		= "cramfs",
-	.get_sb		= cramfs_get_sb,
-	.kill_sb	= kill_block_super,
+	.mount		= cramfs_mount,
+	.kill_sb	= cramfs_kill_sb,
 	.fs_flags	= FS_REQUIRES_DEV,
 };
+MODULE_ALIAS_FS("cramfs");
 
 static int __init init_cramfs_fs(void)
 {
-	cramfs_uncompress_init();
-	return register_filesystem(&cramfs_fs_type);
+	int rv;
+
+	rv = cramfs_uncompress_init();
+	if (rv < 0)
+		return rv;
+	rv = register_filesystem(&cramfs_fs_type);
+	if (rv < 0)
+		cramfs_uncompress_exit();
+	return rv;
 }
 
 static void __exit exit_cramfs_fs(void)