Re: [PATCH] crypto: s5p-sss.c: Fix kernel Oops in AES-ECB mode

From: Krzysztof Kozlowski
Date: Tue Feb 06 2018 - 07:11:48 EST


On Mon, Feb 5, 2018 at 6:40 PM, Kamil Konieczny
<k.konieczny@xxxxxxxxxxxxxxxxxxx> wrote:
>
> In AES-ECB mode crypt is done with key only, so any use of IV
> can cause kernel Oops, as reported by Anand Moon.
> Fixed it by using IV only in AES-CBC and AES-CTR.
>
> Signed-off-by: Kamil Konieczny <k.konieczny@xxxxxxxxxxxxxxxxxxx>
> Reported-by: Anand Moon <linux.amoon@xxxxxxxxx>
> ---
> 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(-)

Fixes and cc-stable?

Reviewed-by: Krzysztof Kozlowski <krzk@xxxxxxxxxx>

Best regards,
Krzysztof