From 17ecefc9fdd8c554e0d03e5a990daef19f930add Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 19 Aug 2025 10:25:01 +0200 Subject: [PATCH] block: don't silently ignore metadata for sync read/write [ Upstream commit 2729a60bbfb9215997f25372ebe9b7964f038296 ] The block fops don't try to handle metadata for synchronous requests, probably because the completion handler looks at dio->iocb which is not valid for synchronous requests. But silently ignoring metadata (or warning in case of __blkdev_direct_IO_simple) is a really bad idea as that can cause silent data corruption if a user ever shows up. Instead simply handle metadata for synchronous requests as the completion handler can simply check for bio_integrity() as the block layer default integrity will already be freed at this point, and thus bio_integrity() will only return true for user mapped integrity. Fixes: 3d8b5a22d404 ("block: add support to pass user meta buffer") Signed-off-by: Christoph Hellwig Link: https://lore.kernel.org/20250819082517.2038819-3-hch@lst.de Reviewed-by: Martin K. Petersen Signed-off-by: Christian Brauner Signed-off-by: Sasha Levin --- block/fops.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/block/fops.c b/block/fops.c index e7bfe65c57f2..d62fbefb2e67 100644 --- a/block/fops.c +++ b/block/fops.c @@ -55,7 +55,6 @@ static ssize_t __blkdev_direct_IO_simple(struct kiocb *iocb, struct bio bio; ssize_t ret; - WARN_ON_ONCE(iocb->ki_flags & IOCB_HAS_METADATA); if (nr_pages <= DIO_INLINE_BIO_VECS) vecs = inline_vecs; else { @@ -132,7 +131,7 @@ static void blkdev_bio_end_io(struct bio *bio) if (bio->bi_status && !dio->bio.bi_status) dio->bio.bi_status = bio->bi_status; - if (!is_sync && (dio->iocb->ki_flags & IOCB_HAS_METADATA)) + if (bio_integrity(bio)) bio_integrity_unmap_user(bio); if (atomic_dec_and_test(&dio->ref)) { @@ -234,7 +233,7 @@ static ssize_t __blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter, } bio->bi_opf |= REQ_NOWAIT; } - if (!is_sync && (iocb->ki_flags & IOCB_HAS_METADATA)) { + if (iocb->ki_flags & IOCB_HAS_METADATA) { ret = bio_integrity_map_iter(bio, iocb->private); if (unlikely(ret)) goto fail; @@ -302,7 +301,7 @@ static void blkdev_bio_end_io_async(struct bio *bio) ret = blk_status_to_errno(bio->bi_status); } - if (iocb->ki_flags & IOCB_HAS_METADATA) + if (bio_integrity(bio)) bio_integrity_unmap_user(bio); iocb->ki_complete(iocb, ret); @@ -423,7 +422,8 @@ static ssize_t blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter) } nr_pages = bio_iov_vecs_to_alloc(iter, BIO_MAX_VECS + 1); - if (likely(nr_pages <= BIO_MAX_VECS)) { + if (likely(nr_pages <= BIO_MAX_VECS && + !(iocb->ki_flags & IOCB_HAS_METADATA))) { if (is_sync_kiocb(iocb)) return __blkdev_direct_IO_simple(iocb, iter, bdev, nr_pages);