diff options
| author | Keith Busch <kbusch@kernel.org> | 2022-07-12 08:32:55 -0700 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2022-08-02 21:08:54 -0600 |
| commit | 34cdb8c825f28a5c91c5336a80967533da57da74 (patch) | |
| tree | c3cf2f81d5b7294b1cc104394e41d338f1771f96 /block | |
| parent | 325347d965e7ccf5424a05398807a6d801846612 (diff) | |
| download | lwn-34cdb8c825f28a5c91c5336a80967533da57da74.tar.gz lwn-34cdb8c825f28a5c91c5336a80967533da57da74.zip | |
block: ensure bio_iov_add_page can't fail
Adding the page could fail on the bio_full() condition, which checks for
either exceeding the bio's max segments or total size exceeding
UINT_MAX. We already ensure the max segments can't be exceeded, so just
ensure the total size won't reach the limit. This simplifies error
handling and removes unnecessary repeated bio_full() checks.
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20220712153256.2202024-2-kbusch@fb.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block')
| -rw-r--r-- | block/bio.c | 19 |
1 files changed, 9 insertions, 10 deletions
diff --git a/block/bio.c b/block/bio.c index d7c2536a5871..4740ba3cb9df 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1165,8 +1165,6 @@ static int bio_iov_add_page(struct bio *bio, struct page *page, bool same_page = false; if (!__bio_try_merge_page(bio, page, len, offset, &same_page)) { - if (WARN_ON_ONCE(bio_full(bio, len))) - return -EINVAL; __bio_add_page(bio, page, len, offset); return 0; } @@ -1228,7 +1226,8 @@ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) * result to ensure the bio's total size is correct. The remainder of * the iov data will be picked up in the next bio iteration. */ - size = iov_iter_get_pages(iter, pages, LONG_MAX, nr_pages, &offset); + size = iov_iter_get_pages(iter, pages, UINT_MAX - bio->bi_iter.bi_size, + nr_pages, &offset); if (size > 0) size = ALIGN_DOWN(size, bdev_logical_block_size(bio->bi_bdev)); if (unlikely(size <= 0)) @@ -1238,16 +1237,16 @@ static int __bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter) struct page *page = pages[i]; len = min_t(size_t, PAGE_SIZE - offset, left); - if (bio_op(bio) == REQ_OP_ZONE_APPEND) + if (bio_op(bio) == REQ_OP_ZONE_APPEND) { ret = bio_iov_add_zone_append_page(bio, page, len, offset); - else - ret = bio_iov_add_page(bio, page, len, offset); + if (ret) { + bio_put_pages(pages + i, left, offset); + break; + } + } else + bio_iov_add_page(bio, page, len, offset); - if (ret) { - bio_put_pages(pages + i, left, offset); - break; - } offset = 0; } |