From b2174eebd1fadb76454dad09a1dacbc17081e6b0 Mon Sep 17 00:00:00 2001 From: Huang Ying Date: Mon, 16 Mar 2009 17:44:33 +0000 Subject: [PATCH] dm crypt: fix kcryptd_async_done parameter In the async encryption-complete function (kcryptd_async_done), the crypto_async_request passed in may be different from the one passed to crypto_ablkcipher_encrypt/decrypt. Only crypto_async_request->data is guaranteed to be same as the one passed in. The current kcryptd_async_done uses the passed-in crypto_async_request directly which may cause the AES-NI-based AES algorithm implementation to panic. This patch fixes this bug by only using crypto_async_request->data, which points to dm_crypt_request, the crypto_async_request passed in. The original data (convert_context) is gotten from dm_crypt_request. [mbroz@redhat.com: reworked] Cc: stable@kernel.org Signed-off-by: Huang Ying Cc: Herbert Xu Signed-off-by: Milan Broz Signed-off-by: Andrew Morton Signed-off-by: Alasdair G Kergon --- drivers/md/dm-crypt.c | 26 +++++++++++++++++++++----- 1 file changed, 21 insertions(+), 5 deletions(-) diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c index 35bda49796fb..ebab49f8cc1d 100644 --- a/drivers/md/dm-crypt.c +++ b/drivers/md/dm-crypt.c @@ -60,6 +60,7 @@ struct dm_crypt_io { }; struct dm_crypt_request { + struct convert_context *ctx; struct scatterlist sg_in; struct scatterlist sg_out; }; @@ -335,6 +336,18 @@ static void crypt_convert_init(struct crypt_config *cc, init_completion(&ctx->restart); } +static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc, + struct ablkcipher_request *req) +{ + return (struct dm_crypt_request *)((char *)req + cc->dmreq_start); +} + +static struct ablkcipher_request *req_of_dmreq(struct crypt_config *cc, + struct dm_crypt_request *dmreq) +{ + return (struct ablkcipher_request *)((char *)dmreq - cc->dmreq_start); +} + static int crypt_convert_block(struct crypt_config *cc, struct convert_context *ctx, struct ablkcipher_request *req) @@ -345,10 +358,11 @@ static int crypt_convert_block(struct crypt_config *cc, u8 *iv; int r = 0; - dmreq = (struct dm_crypt_request *)((char *)req + cc->dmreq_start); + dmreq = dmreq_of_req(cc, req); iv = (u8 *)ALIGN((unsigned long)(dmreq + 1), crypto_ablkcipher_alignmask(cc->tfm) + 1); + dmreq->ctx = ctx; sg_init_table(&dmreq->sg_in, 1); sg_set_page(&dmreq->sg_in, bv_in->bv_page, 1 << SECTOR_SHIFT, bv_in->bv_offset + ctx->offset_in); @@ -395,8 +409,9 @@ static void crypt_alloc_req(struct crypt_config *cc, cc->req = mempool_alloc(cc->req_pool, GFP_NOIO); ablkcipher_request_set_tfm(cc->req, cc->tfm); ablkcipher_request_set_callback(cc->req, CRYPTO_TFM_REQ_MAY_BACKLOG | - CRYPTO_TFM_REQ_MAY_SLEEP, - kcryptd_async_done, ctx); + CRYPTO_TFM_REQ_MAY_SLEEP, + kcryptd_async_done, + dmreq_of_req(cc, cc->req)); } /* @@ -821,7 +836,8 @@ static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) static void kcryptd_async_done(struct crypto_async_request *async_req, int error) { - struct convert_context *ctx = async_req->data; + struct dm_crypt_request *dmreq = async_req->data; + struct convert_context *ctx = dmreq->ctx; struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); struct crypt_config *cc = io->target->private; @@ -830,7 +846,7 @@ static void kcryptd_async_done(struct crypto_async_request *async_req, return; } - mempool_free(ablkcipher_request_cast(async_req), cc->req_pool); + mempool_free(req_of_dmreq(cc, dmreq), cc->req_pool); if (!atomic_dec_and_test(&ctx->pending)) return;