mirrors
/
linux-stable
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
1
0
Fork 0
Code Issues Releases Wiki Activity

block: move the bi_size overflow check in __bio_try_merge_page 

Checking for availability in bi_size in a function that attempts to
merge into an existing segment is a bit odd, as the limit also applies
when adding a new segment.  This code works fine as we always call
__bio_try_merge_page, but contributes to sub-optimal calling conventions
and doesn't lead to clear code.

Move it to two of the callers instead, the third one already has a more
strict check that includes max_hw_segments anyway.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jinyoung Choi <j-young.choi@samsung.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Link: https://lore.kernel.org/r/20230724165433.117645-6-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Hellwig 2023-07-24 09:54:30 -07:00 committed by Jens Axboe
parent 0eca8b6f97
commit 613699050a
1 changed files with 5 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
block/bio.c
View File

@ -949,10 +949,6 @@ static bool __bio_try_merge_page(struct bio *bio, struct page *page,
if (!page_is_mergeable(bv, page, len, off, same_page))
return false;
if (bio->bi_iter.bi_size > UINT_MAX - len) {
*same_page = false;
return false;
}
bv->bv_len += len;
bio->bi_iter.bi_size += len;
return true;
@ -1123,6 +1119,8 @@ int bio_add_page(struct bio *bio, struct page *page,
if (WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)))
return 0;
if (bio->bi_iter.bi_size > UINT_MAX - len)
return 0;
if (bio->bi_vcnt > 0 &&
__bio_try_merge_page(bio, page, len, offset, &same_page))
@ -1204,6 +1202,9 @@ static int bio_iov_add_page(struct bio *bio, struct page *page,
{
bool same_page = false;
if (WARN_ON_ONCE(bio->bi_iter.bi_size > UINT_MAX - len))
return -EIO;
if (bio->bi_vcnt > 0 &&
__bio_try_merge_page(bio, page, len, offset, &same_page)) {
if (same_page)