Commit 4e594098 authored by Milan Broz's avatar Milan Broz Committed by Alasdair G Kergon

dm crypt: fix async inc_pending

The pending reference count must be incremented *before* the async work is
queued to another thread, not after.  Otherwise there's a race if the
work completes and decrements the reference count before it gets incremented.
Signed-off-by: default avatarMilan Broz <mbroz@redhat.com>
Signed-off-by: default avatarAlasdair G Kergon <agk@redhat.com>
parent 6c031f41
...@@ -719,16 +719,15 @@ static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) ...@@ -719,16 +719,15 @@ static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
remaining -= clone->bi_size; remaining -= clone->bi_size;
crypt_inc_pending(io);
r = crypt_convert(cc, &io->ctx); r = crypt_convert(cc, &io->ctx);
if (atomic_dec_and_test(&io->ctx.pending)) { if (atomic_dec_and_test(&io->ctx.pending)) {
/* processed, no running async crypto */ /* processed, no running async crypto */
crypt_inc_pending(io);
kcryptd_crypt_write_io_submit(io, r, 0); kcryptd_crypt_write_io_submit(io, r, 0);
if (unlikely(r < 0)) if (unlikely(r < 0))
break; break;
} else }
crypt_inc_pending(io);
/* out of memory -> run queues */ /* out of memory -> run queues */
if (unlikely(remaining)) { if (unlikely(remaining)) {
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment