diff options
Diffstat (limited to 'fs/cramfs/inode.c')
-rw-r--r-- | fs/cramfs/inode.c | 36 |
1 files changed, 26 insertions, 10 deletions
diff --git a/fs/cramfs/inode.c b/fs/cramfs/inode.c index a07338d2d140..46e52980b98a 100644 --- a/fs/cramfs/inode.c +++ b/fs/cramfs/inode.c @@ -459,11 +459,14 @@ static struct dentry * cramfs_lookup(struct inode *dir, struct dentry *dentry, s 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; @@ -472,30 +475,43 @@ static int cramfs_readpage(struct file *file, struct page * page) start_offset = OFFSET(inode) + maxblock*4; 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); + 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); - pgdata = kmap(page); + if (compr_len == 0) ; /* hole */ - else if (compr_len > (PAGE_CACHE_SIZE << 1)) - printk(KERN_ERR "cramfs: bad compressed blocksize %u\n", compr_len); - else { + 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); 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 const struct address_space_operations cramfs_aops = { |