From: Kamil Konieczny Subject: [PATCH v2] crypto: s5p-sss.c: Fix kernel Oops in AES-ECB mode Date: Wed, 07 Feb 2018 11:38:57 +0100 Message-ID: <64a5e903-c6c1-28f4-8af4-dbbd7bef17ef@partner.samsung.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: Krzysztof Kozlowski , Vladimir Zapolskiy , "David S. Miller" , Anand Moon , Bartlomiej Zolnierkiewicz , Marek Szyprowski , linux-crypto@vger.kernel.org, linux-samsung-soc@vger.kernel.org, linux-kernel To: Herbert Xu Return-path: Content-language: en-US Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-crypto.vger.kernel.org In AES-ECB mode crypt is done with key only, so any use of IV can cause kernel Oops. Use IV only in AES-CBC and AES-CTR. Signed-off-by: Kamil Konieczny Reported-by: Anand Moon Reviewed-by: Krzysztof Kozlowski Tested-by: Anand Moon Cc: stable@vger.kernel.org Fixes: 8f9702aad138 ("crypto: s5p-sss - validate iv before memcpy") --- version 2: Change commit message. Tested on Odroid XU4/HC1, kernel 4.15 with following command: fallocate -l 128MiB /tmp/test.bin dd if=/dev/urandom of=/tmp/testkey.key bs=128 count=1 sync cryptsetup luksFormat --debug -q -d /tmp/testkey.key \ --cipher aes-cbc-essiv:sha256 -h sha256 -s 128 /tmp/test.bin The original report by Anand Moon: https://www.spinics.net/lists/linux-crypto/msg31180.html Oops reproduced with cryptsetup 2.0.0, kernel 4.15, in .config in crypto API ECB support was turned off, and s5p-sss AES driver on. cryptsetup is using aes-ecb and has req->info in aes_ctx set to 0x10, which caused Oops: [ 2078.683779] Internal error: Oops: 17 [#1] PREEMPT SMP ARM [ 2078.689148] Modules linked in: algif_skcipher af_alg sd_mod sg evdev uas usb_storage scsi_mod gpio_keys fbtft(C) spidev spi_s3c64xx ipv6 [ 2078.701377] CPU: 1 PID: 15 Comm: ksoftirqd/1 Tainted: G C 4.15.0-rc9-xu4krck #1 [ 2078.709861] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) [ 2078.715932] PC is at memcpy+0x80/0x330 [ 2078.719652] LR is at s5p_tasklet_cb+0x19c/0x328 drivers/crypto/s5p-sss.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/crypto/s5p-sss.c b/drivers/crypto/s5p-sss.c index 142c6020cec7..5c0496d1ed41 100644 --- a/drivers/crypto/s5p-sss.c +++ b/drivers/crypto/s5p-sss.c @@ -1926,15 +1926,21 @@ static void s5p_aes_crypt_start(struct s5p_aes_dev *dev, unsigned long mode) uint32_t aes_control; unsigned long flags; int err; + u8 *iv; aes_control = SSS_AES_KEY_CHANGE_MODE; if (mode & FLAGS_AES_DECRYPT) aes_control |= SSS_AES_MODE_DECRYPT; - if ((mode & FLAGS_AES_MODE_MASK) == FLAGS_AES_CBC) + if ((mode & FLAGS_AES_MODE_MASK) == FLAGS_AES_CBC) { aes_control |= SSS_AES_CHAIN_MODE_CBC; - else if ((mode & FLAGS_AES_MODE_MASK) == FLAGS_AES_CTR) + iv = req->info; + } else if ((mode & FLAGS_AES_MODE_MASK) == FLAGS_AES_CTR) { aes_control |= SSS_AES_CHAIN_MODE_CTR; + iv = req->info; + } else { + iv = NULL; /* AES_ECB */ + } if (dev->ctx->keylen == AES_KEYSIZE_192) aes_control |= SSS_AES_KEY_SIZE_192; @@ -1965,7 +1971,7 @@ static void s5p_aes_crypt_start(struct s5p_aes_dev *dev, unsigned long mode) goto outdata_error; SSS_AES_WRITE(dev, AES_CONTROL, aes_control); - s5p_set_aes(dev, dev->ctx->aes_key, req->info, dev->ctx->keylen); + s5p_set_aes(dev, dev->ctx->aes_key, iv, dev->ctx->keylen); s5p_set_dma_indata(dev, dev->sg_src); s5p_set_dma_outdata(dev, dev->sg_dst); -- 2.16.0