From: Christoph Manszewski Subject: [PATCH v2 1/4] crypto: s5p-sss: Fix race in error handling Date: Mon, 17 Sep 2018 17:09:27 +0200 Message-ID: <20180917151006eucas1p2226806b94605b061bc1bc3e9b5a6c495~VOIhXssSK0729007290eucas1p25@eucas1p2.samsung.com> References: <1537196970-5987-1-git-send-email-c.manszewski@samsung.com> Content-Type: text/plain; charset="utf-8" Cc: Christoph Manszewski , Krzysztof Kozlowski , Vladimir Zapolskiy , Kamil Konieczny , Herbert Xu , "David S. Miller" , linux-samsung-soc@vger.kernel.org, linux-kernel@vger.kernel.org, Bartlomiej Zolnierkiewicz To: linux-crypto@vger.kernel.org Return-path: In-Reply-To: <1537196970-5987-1-git-send-email-c.manszewski@samsung.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-crypto.vger.kernel.org Remove a race condition introduced by error path in functions: s5p_aes_interrupt and s5p_aes_crypt_start. Setting the busy field of struct s5p_aes_dev to false made it possible for s5p_tasklet_cb to change the req field, before s5p_aes_complete was called. Change the first parameter of s5p_aes_complete to struct ablkcipher_request. Before spin_unlock, make a copy of the currently handled request, to ensure s5p_aes_complete function call with the correct request. Signed-off-by: Christoph Manszewski --- drivers/crypto/s5p-sss.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/crypto/s5p-sss.c b/drivers/crypto/s5p-sss.c index faa282074e5a..9021ad9df0c4 100644 --- a/drivers/crypto/s5p-sss.c +++ b/drivers/crypto/s5p-sss.c @@ -475,9 +475,9 @@ static void s5p_sg_done(struct s5p_aes_dev *dev) } /* Calls the completion. Cannot be called with dev->lock hold. */ -static void s5p_aes_complete(struct s5p_aes_dev *dev, int err) +static void s5p_aes_complete(struct ablkcipher_request *req, int err) { - dev->req->base.complete(&dev->req->base, err); + req->base.complete(&req->base, err); } static void s5p_unset_outdata(struct s5p_aes_dev *dev) @@ -655,6 +655,7 @@ static irqreturn_t s5p_aes_interrupt(int irq, void *dev_id) { struct platform_device *pdev = dev_id; struct s5p_aes_dev *dev = platform_get_drvdata(pdev); + struct ablkcipher_request *req; int err_dma_tx = 0; int err_dma_rx = 0; int err_dma_hx = 0; @@ -727,7 +728,7 @@ static irqreturn_t s5p_aes_interrupt(int irq, void *dev_id) spin_unlock_irqrestore(&dev->lock, flags); - s5p_aes_complete(dev, 0); + s5p_aes_complete(dev->req, 0); /* Device is still busy */ tasklet_schedule(&dev->tasklet); } else { @@ -752,11 +753,12 @@ static irqreturn_t s5p_aes_interrupt(int irq, void *dev_id) error: s5p_sg_done(dev); dev->busy = false; + req = dev->req; if (err_dma_hx == 1) s5p_set_dma_hashdata(dev, dev->hash_sg_iter); spin_unlock_irqrestore(&dev->lock, flags); - s5p_aes_complete(dev, err); + s5p_aes_complete(req, err); hash_irq_end: /* @@ -1983,7 +1985,7 @@ static void s5p_aes_crypt_start(struct s5p_aes_dev *dev, unsigned long mode) s5p_sg_done(dev); dev->busy = false; spin_unlock_irqrestore(&dev->lock, flags); - s5p_aes_complete(dev, err); + s5p_aes_complete(req, err); } static void s5p_tasklet_cb(unsigned long data) -- 2.7.4