6.8-stable review patch. If anyone has any objections, please let me know.
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From: Christoph Hellwig hch@lst.de
[ 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@syzkaller.appspotmail.com Signed-off-by: Christoph Hellwig hch@lst.de Tested-by: syzbot+0a3683a0a6fecf909244@syzkaller.appspotmail.com Link: https://lore.kernel.org/r/20240503081042.2078062-1-hch@lst.de Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- block/fops.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
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;