Similarly to 26064d3e2b4d ("block: fix adding folio to bio"), if
we attempt to add a folio that is larger than 4GB, we'll silently
truncate the offset and len. Widen the parameters to size_t, assert
that the length is less than 4GB and set the first page that contains
the interesting data rather than the first page of the folio.
Fixes: 26db5ee15851 (block: add a bvec_set_folio helper)
Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx>
---
include/linux/bvec.h | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/include/linux/bvec.h b/include/linux/bvec.h
index 204b22a99c4b..0a80e1f9aa20 100644
--- a/include/linux/bvec.h
+++ b/include/linux/bvec.h
@@ -57,9 +57,12 @@ static inline void bvec_set_page(struct bio_vec *bv, struct page *page,
* @offset: offset into the folio
*/
static inline void bvec_set_folio(struct bio_vec *bv, struct folio *folio,
- unsigned int len, unsigned int offset)
+ size_t len, size_t offset)
{
- bvec_set_page(bv, &folio->page, len, offset);
+ unsigned long nr = offset / PAGE_SIZE;
+
+ WARN_ON_ONCE(len > UINT_MAX);
+ bvec_set_page(bv, folio_page(folio, nr), len, offset % PAGE_SIZE);
}
/**
--
2.47.2
