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 6.6-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-6.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 3b61b08a4ea76aeb9d5626a079089ed24f643ce6 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 73e42742543f6..1df187b306792 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;