Commit fab5a60a authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Check input buffer size in zisofs 

This uses the new deflateBound() thing to sanity-check the input to the
zlib decompressor before we even bother to start reading in the blocks.

Problem noted by Tim Yamin <plasmaroo@gentoo.org>
parent 243393c9

fs/isofs/compress.c

+6 −0
Original line number Diff line number Diff line
@@ -129,8 +129,14 @@ static int zisofs_readpage(struct file *file, struct page *page) 
	cend = le32_to_cpu(*(__le32 *)(bh->b_data + (blockendptr & bufmask)));

	brelse(bh);



	if (cstart > cend)

		goto eio;

		

	csize = cend-cstart;



	if (csize > deflateBound(1UL << zisofs_block_shift))

		goto eio;



	/* Now page[] contains an array of pages, any of which can be NULL,

	   and the locks on which we hold.  We should now read the data and

	   release the pages.  If the pages are NULL the decompressed data