From b989de221a8399d42aede6da03297cad3330f12a Mon Sep 17 00:00:00 2001
From: Theodore Ts'o <tytso@mit.edu>
Date: Mon, 4 Nov 2019 16:43:41 -0500
Subject: [PATCH 01/10] libext2fs: fix bug when reading or writing more than
 2GB in unix_io

If count * block_size exceeds 2GB, we will overflow a 32-bit signed
integer value.  This shouldn't happen in practice except for
fuzz-corrupted file systems, but let's fix the code so it's correct.

Bug: https://github.com/tytso/e2fsprogs/issues/24
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
---
 lib/ext2fs/unix_io.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/ext2fs/unix_io.c b/lib/ext2fs/unix_io.c
index 74fc8a75..628e60c3 100644
--- a/lib/ext2fs/unix_io.c
+++ b/lib/ext2fs/unix_io.c
@@ -166,7 +166,7 @@ static errcode_t raw_read_blk(io_channel channel,
 	unsigned char	*buf = bufv;
 	ssize_t		really_read = 0;
 
-	size = (count < 0) ? -count : count * channel->block_size;
+	size = (count < 0) ? -count : (ext2_loff_t) count * channel->block_size;
 	data->io_stats.bytes_read += size;
 	location = ((ext2_loff_t) block * channel->block_size) + data->offset;
 
@@ -275,7 +275,7 @@ static errcode_t raw_write_blk(io_channel channel,
 		if (count < 0)
 			size = -count;
 		else
-			size = count * channel->block_size;
+			size = (ext2_loff_t) count * channel->block_size;
 	}
 	data->io_stats.bytes_written += size;
 
-- 
2.21.1