Commit 39e16050 authored by Martin K. Petersen's avatar Martin K. Petersen Committed by Jens Axboe
Browse files

block: integrity: Do not call set_page_dirty_lock() 



Placing multiple protection information buffers inside the same page
can lead to oopses because set_page_dirty_lock() can't be called from
interrupt context.

Since a protection information buffer is not backed by a file there is
no point in setting its page dirty, there is nothing to synchronize.
Drop the call to set_page_dirty_lock() and remove the last argument to
bio_integrity_unpin_bvec().

Cc: stable@vger.kernel.org
Fixes: 492c5d45 ("block: bio-integrity: directly map user buffers")
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: default avatarKeith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/yq1v7r3ev9g.fsf@ca-mkp.ca.oracle.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 0b7a4817

block/bio-integrity.c

+6 −11
Original line number Diff line number Diff line
@@ -66,17 +66,13 @@ struct bio_integrity_payload *bio_integrity_alloc(struct bio *bio, 
}

EXPORT_SYMBOL(bio_integrity_alloc);



static void bio_integrity_unpin_bvec(struct bio_vec *bv, int nr_vecs,

				     bool dirty)

static void bio_integrity_unpin_bvec(struct bio_vec *bv, int nr_vecs)

{

	int i;



	for (i = 0; i < nr_vecs; i++) {

		if (dirty && !PageCompound(bv[i].bv_page))

			set_page_dirty_lock(bv[i].bv_page);

	for (i = 0; i < nr_vecs; i++)

		unpin_user_page(bv[i].bv_page);

}

}



static void bio_integrity_uncopy_user(struct bio_integrity_payload *bip)

{
@@ -91,7 +87,7 @@ static void bio_integrity_uncopy_user(struct bio_integrity_payload *bip) 
	ret = copy_to_iter(bvec_virt(bounce_bvec), bytes, &orig_iter);

	WARN_ON_ONCE(ret != bytes);



	bio_integrity_unpin_bvec(orig_bvecs, orig_nr_vecs, true);

	bio_integrity_unpin_bvec(orig_bvecs, orig_nr_vecs);

}



/**
@@ -111,8 +107,7 @@ void bio_integrity_unmap_user(struct bio *bio) 
		return;

	}



	bio_integrity_unpin_bvec(bip->bip_vec, bip->bip_max_vcnt,

			bio_data_dir(bio) == READ);

	bio_integrity_unpin_bvec(bip->bip_vec, bip->bip_max_vcnt);

}



/**
@@ -198,7 +193,7 @@ static int bio_integrity_copy_user(struct bio *bio, struct bio_vec *bvec, 
	}



	if (write)

		bio_integrity_unpin_bvec(bvec, nr_vecs, false);

		bio_integrity_unpin_bvec(bvec, nr_vecs);

	else

		memcpy(&bip->bip_vec[1], bvec, nr_vecs * sizeof(*bvec));
@@ -319,7 +314,7 @@ int bio_integrity_map_user(struct bio *bio, struct iov_iter *iter) 
	return 0;



release_pages:

	bio_integrity_unpin_bvec(bvec, nr_bvecs, false);

	bio_integrity_unpin_bvec(bvec, nr_bvecs);

free_bvec:

	if (bvec != stack_vec)

		kfree(bvec);