This is a note to let you know that I've just added the patch titled block: Fix page refcounts for unaligned buffers in __bio_release_pages() to the 6.7-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: block-fix-page-refcounts-for-unaligned-buffers-in-__.patch and it can be found in the queue-6.7 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 7ecdaec0258a6c626fbc07eb11098f645bde49f5 Author: Tony Battersby <tonyb@xxxxxxxxxxxxxxx> Date: Thu Feb 29 13:08:09 2024 -0500 block: Fix page refcounts for unaligned buffers in __bio_release_pages() [ Upstream commit 38b43539d64b2fa020b3b9a752a986769f87f7a6 ] Fix an incorrect number of pages being released for buffers that do not start at the beginning of a page. Fixes: 1b151e2435fc ("block: Remove special-casing of compound pages") Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Tony Battersby <tonyb@xxxxxxxxxxxxxxx> Tested-by: Greg Edwards <gedwards@xxxxxxx> Link: https://lore.kernel.org/r/86e592a9-98d4-4cff-a646-0c0084328356@xxxxxxxxxxxxxxx Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/block/bio.c b/block/bio.c index 270f6b99926ea..62419aa09d731 100644 --- a/block/bio.c +++ b/block/bio.c @@ -1149,7 +1149,7 @@ 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); @@ -1157,10 +1157,11 @@ 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);