Commit 38b43539 authored by Tony Battersby's avatar Tony Battersby Committed by Jens Axboe
Browse files

block: Fix page refcounts for unaligned buffers in __bio_release_pages() 



Fix an incorrect number of pages being released for buffers that do not
start at the beginning of a page.

Fixes: 1b151e24 ("block: Remove special-casing of compound pages")
Cc: stable@vger.kernel.org
Signed-off-by: default avatarTony Battersby <tonyb@cybernetics.com>
Tested-by: default avatarGreg Edwards <gedwards@ddn.com>
Link: https://lore.kernel.org/r/86e592a9-98d4-4cff-a646-0c0084328356@cybernetics.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 26828324

block/bio.c

+4 −3
Original line number Diff line number Diff line
@@ -1153,7 +1153,7 @@ void __bio_release_pages(struct bio *bio, bool mark_dirty) 


	bio_for_each_folio_all(fi, bio) {

		struct page *page;

		size_t done = 0;

		size_t nr_pages;



		if (mark_dirty) {

			folio_lock(fi.folio);
@@ -1161,10 +1161,11 @@ void __bio_release_pages(struct bio *bio, bool mark_dirty) 
			folio_unlock(fi.folio);

		}

		page = folio_page(fi.folio, fi.offset / PAGE_SIZE);

		nr_pages = (fi.offset + fi.length - 1) / PAGE_SIZE -

			   fi.offset / PAGE_SIZE + 1;

		do {

			bio_release_page(bio, page++);

			done += PAGE_SIZE;

		} while (done < fi.length);

		} while (--nr_pages != 0);

	}

}

EXPORT_SYMBOL_GPL(__bio_release_pages);