diff options
| author | Keith Busch <kbusch@kernel.org> | 2026-07-20 13:10:57 -0700 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2026-07-31 08:10:49 -0600 |
| commit | 14b007e178811db72fbb1ebb3535160db6ec1e6a (patch) | |
| tree | ccecab167f93099ba4ae74ca7148e5d3d9aad9a7 /include/linux | |
| parent | c5059c1af2bd22bc1435b99d27d800164162cb72 (diff) | |
block: validate user space vectors during extraction
The bio-based drivers don't necessarily check the alignment split, and
stacking block drivers don't always handle a misalignment detected after
submitting the bio. Validate user vectors against the device's
dma_alignment as the bio is built from the iov_iter, rejecting
misaligned early with -EINVAL.
Cc: stable@vger.kernel.org
Fixes: 5ff3f74e145a ("block: simplify direct io validity check")
Fixes: 7eac33186957 ("iomap: simplify direct io validity check")
Reviewed-by: Hannes Reinecke <hare@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://patch.msgid.link/20260720201057.1862857-6-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/bio.h | 2 | ||||
| -rw-r--r-- | include/linux/uio.h | 10 |
2 files changed, 10 insertions, 2 deletions
diff --git a/include/linux/bio.h b/include/linux/bio.h index 8f33f717b14f..ce34ea49ef35 100644 --- a/include/linux/bio.h +++ b/include/linux/bio.h @@ -477,7 +477,7 @@ int bdev_rw_virt(struct block_device *bdev, sector_t sector, void *data, size_t len, enum req_op op); int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter, - unsigned len_align_mask); + unsigned mem_align_mask, unsigned len_align_mask); void bio_iov_bvec_set(struct bio *bio, const struct iov_iter *iter); void __bio_release_pages(struct bio *bio, bool mark_dirty); diff --git a/include/linux/uio.h b/include/linux/uio.h index a9bc5b3067e3..fe2e985d74d2 100644 --- a/include/linux/uio.h +++ b/include/linux/uio.h @@ -389,9 +389,17 @@ ssize_t iov_iter_extract_pages(struct iov_iter *i, struct page ***pages, size_t maxsize, unsigned int maxpages, iov_iter_extraction_t extraction_flags, size_t *offset0); +/* + * Block-layer consumers (e.g. bio_iov_iter_get_pages()) require that the + * segments of an ITER_BVEC iterator are already aligned to the target device's + * DMA alignment, and forward them as-is. In-kernel users that build their own + * bvecs must not create sub-aligned segments; iov_iter_extract_bvecs() enforces + * the same for the segments it extracts via @mem_align_mask. + */ ssize_t iov_iter_extract_bvecs(struct iov_iter *iter, struct bio_vec *bv, size_t max_size, unsigned short *nr_vecs, - unsigned short max_vecs, iov_iter_extraction_t extraction_flags); + unsigned short max_vecs, unsigned mem_align_mask, + iov_iter_extraction_t extraction_flags); /** * iov_iter_extract_will_pin - Indicate how pages from the iterator will be retained |