From: Hou Tao <houtao1@xxxxxxxxxx>
Both kcryptd_io_read() and kcryptd_crypt_write_convert() will invoke
crypt_alloc_buffer() to allocate a new bio. Both of these two callers
initialize bi_iter.bi_sector for the new bio separatedly after
crypt_alloc_buffer() returns. However, kcryptd_crypt_write_convert()
will copy the bi_iter of the new bio into ctx.iter_out or ctx.iter_in.
Although it doesn't incur any harm now, it is better to fully initialize
bi_iter before it is used.
Therefore, initialize bi_iter.bi_sector in crypt_alloc_buffer() instead.
Signed-off-by: Hou Tao <houtao1@xxxxxxxxxx>
---
drivers/md/dm-crypt.c | 8 +++-----
1 file changed, 3 insertions(+), 5 deletions(-)
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 424c8fc3f0ada..551c934bfc501 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -1719,6 +1719,7 @@ static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned int size)
clone->bi_private = io;
clone->bi_end_io = crypt_endio;
clone->bi_ioprio = io->base_bio->bi_ioprio;
+ clone->bi_iter.bi_sector = cc->start + io->sector;
remaining_size = size;
@@ -1909,7 +1910,6 @@ static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp)
crypt_dec_pending(io);
return 1;
}
- clone->bi_iter.bi_sector = cc->start + io->sector;
crypt_convert_init(cc, &io->ctx, clone, clone, io->sector);
io->saved_bi_iter = clone->bi_iter;
dm_submit_bio_remap(io->base_bio, clone);
@@ -1925,13 +1925,13 @@ static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp)
clone = bio_alloc_clone(cc->dev->bdev, io->base_bio, gfp, &cc->bs);
if (!clone)
return 1;
+
+ clone->bi_iter.bi_sector = cc->start + io->sector;
clone->bi_private = io;
clone->bi_end_io = crypt_endio;
crypt_inc_pending(io);
- clone->bi_iter.bi_sector = cc->start + io->sector;
-
if (dm_crypt_integrity_io_alloc(io, clone)) {
crypt_dec_pending(io);
bio_put(clone);
@@ -2039,8 +2039,6 @@ static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async)
/* crypt_convert should have filled the clone bio */
BUG_ON(io->ctx.iter_out.bi_size);
- clone->bi_iter.bi_sector = cc->start + io->sector;
-
if ((likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) ||
test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) {
dm_submit_bio_remap(io->base_bio, clone);
--
2.29.2
