On Tue, Sep 15 2020 at 11:53pm -0400, Eric Biggers <ebiggers@xxxxxxxxxx> wrote: > From: Eric Biggers <ebiggers@xxxxxxxxxx> > > bio_crypt_clone() assumes its gfp_mask argument always includes > __GFP_DIRECT_RECLAIM, so that the mempool_alloc() will always succeed. > > However, bio_crypt_clone() might be called with GFP_ATOMIC via > setup_clone() in drivers/md/dm-rq.c, or with GFP_NOWAIT via > kcryptd_io_read() in drivers/md/dm-crypt.c. > > Neither case is currently reachable with a bio that actually has an > encryption context. However, it's fragile to rely on this. Just make > bio_crypt_clone() able to fail, analogous to bio_integrity_clone(). > > Reported-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> > Cc: Satya Tangirala <satyat@xxxxxxxxxx> > Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx> Reviewed-by: Mike Snitzer <snitzer@xxxxxxxxxx>
