This is a note to let you know that I've just added the patch titled
block: refine the EOF check in blkdev_iomap_begin
to the 6.8-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
block-refine-the-eof-check-in-blkdev_iomap_begin.patch
and it can be found in the queue-6.8 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 3427a534dd6828f07e22a444279e1be0593de925
Author: Christoph Hellwig <hch@xxxxxx>
Date: Fri May 3 10:10:42 2024 +0200
block: refine the EOF check in blkdev_iomap_begin
[ Upstream commit 0c12028aec837f5a002009bbf68d179d506510e8 ]
blkdev_iomap_begin rounds down the offset to the logical block size
before stashing it in iomap->offset and checking that it still is
inside the inode size.
Check the i_size check to the raw pos value so that we don't try a
zero size write if iter->pos is unaligned.
Fixes: 487c607df790 ("block: use iomap for writes to block devices")
Reported-by: syzbot+0a3683a0a6fecf909244@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Tested-by: syzbot+0a3683a0a6fecf909244@xxxxxxxxxxxxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/20240503081042.2078062-1-hch@xxxxxx
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/block/fops.c b/block/fops.c
index 0cf8cf72cdfa1..799821040601a 100644
--- a/block/fops.c
+++ b/block/fops.c
@@ -387,7 +387,7 @@ static int blkdev_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
iomap->bdev = bdev;
iomap->offset = ALIGN_DOWN(offset, bdev_logical_block_size(bdev));
- if (iomap->offset >= isize)
+ if (offset >= isize)
return -EIO;
iomap->type = IOMAP_MAPPED;
iomap->addr = iomap->offset;
