From: David VomLehn Date: Thu, 2 Apr 2009 23:59:15 +0000 (-0700) Subject: cramfs: propagate uncompression errors X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=98310e581e098514867573031b2bfa4ba89c0d93;p=linux-2.6-omap-h63xx.git cramfs: propagate uncompression errors Decompression errors can arise due to corruption of compressed blocks on flash or in memory. This patch propagates errors detected during decompression back to the block layer. Signed-off-by: David VomLehn Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- diff --git a/fs/cramfs/inode.c b/fs/cramfs/inode.c index a07338d2d14..46e52980b98 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 = { diff --git a/fs/cramfs/uncompress.c b/fs/cramfs/uncompress.c index fc3ccb74626..023329800d2 100644 --- a/fs/cramfs/uncompress.c +++ b/fs/cramfs/uncompress.c @@ -50,7 +50,7 @@ int cramfs_uncompress_block(void *dst, int dstlen, void *src, int srclen) err: printk("Error %d while decompressing!\n", err); printk("%p(%d)->%p(%d)\n", src, srclen, dst, dstlen); - return 0; + return -EIO; } int cramfs_uncompress_init(void)