On Thu, Jul 01, 2021 at 02:56:36PM -0400, Sean Anderson wrote:
> This fixes at least one oops when using the DCP on ULL. However, I got
> another Oops when running kcapi-dgst-test.sh from the libkcapi test
> suite [1]:
>
> [ 6961.181777] Unable to handle kernel NULL pointer dereference at virtual address 000008f8
> [ 6961.190143] pgd = e59542a6
> [ 6961.192917] [000008f8] *pgd=00000000
> [ 6961.196586] Internal error: Oops: 5 [#1] ARM
> [ 6961.200877] Modules linked in: crypto_user mxs_dcp cfg80211 rfkill des_generic libdes arc4 libarc4 cbc ecb algif_skcipher sha256_generic libsha256 sha1_generic hmac aes_generic libaes cmac sha512_generic md5 md4 algif_hash af_alg i2c_imx ci_hdrc_imx ci_hdrc i2c_core ulpi roles udc_core imx_sdma usb_common firmware_class usbmisc_imx virt_dma phy_mxs_usb nf_tables nfnetlink ip_tables x_tables ipv6 autofs4 [last unloaded: mxs_dcp]
> [ 6961.239228] CPU: 0 PID: 469 Comm: mxs_dcp_chan/ae Not tainted 5.10.46-315-tiago #315
> [ 6961.246988] Hardware name: Freescale i.MX6 Ultralite (Device Tree)
> [ 6961.253201] PC is at memcpy+0xc0/0x330
> [ 6961.256993] LR is at dcp_chan_thread_aes+0x220/0x94c [mxs_dcp]
> [ 6961.262847] pc : [<c053f1e0>] lr : [<bf13cda4>] psr: 800e0013
> [ 6961.269130] sp : cdc09ef4 ip : 00000010 fp : c36e5808
> [ 6961.274370] r10: cdcc3150 r9 : 00000000 r8 : bff46000
> [ 6961.279613] r7 : c36e59d0 r6 : c2e42840 r5 : cdcc3140 r4 : 00000001
> [ 6961.286156] r3 : 000008f9 r2 : 80000000 r1 : 000008f8 r0 : cdc1004f
> [ 6961.292704] Flags: Nzcv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none
> [ 6961.299860] Control: 10c53c7d Table: 83358059 DAC: 00000051
> [ 6961.305628] Process mxs_dcp_chan/ae (pid: 469, stack limit = 0xe1efdc80)
> [ 6961.312346] Stack: (0xcdc09ef4 to 0xcdc0a000)
> [ 6961.316726] 9ee0: cdc1004f 00000001 bf13cda4
> [ 6961.324930] 9f00: 00000000 00000000 c23b41a0 00000000 c36e59d0 00000001 00000010 00000000
> [ 6961.333132] 9f20: 00000000 00000000 c13de2fc 000008f9 8dc13080 00000010 cdcc3150 c21e5010
> [ 6961.341335] 9f40: cdc08000 cdc10040 00000001 bf13fa40 cdc11040 c2e42880 00000002 cc861440
> [ 6961.349535] 9f60: ffffe000 c33dbe00 c332cb40 cdc08000 00000000 bf13cb84 00000000 c3353c54
> [ 6961.357736] 9f80: c33dbe44 c0140d34 cdc08000 c332cb40 c0140c00 00000000 00000000 00000000
> [ 6961.365936] 9fa0: 00000000 00000000 00000000 c0100114 00000000 00000000 00000000 00000000
> [ 6961.374138] 9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> [ 6961.382338] 9fe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000
> [ 6961.390567] [<c053f1e0>] (memcpy) from [<bf13cda4>] (dcp_chan_thread_aes+0x220/0x94c [mxs_dcp])
> [ 6961.399312] [<bf13cda4>] (dcp_chan_thread_aes [mxs_dcp]) from [<c0140d34>] (kthread+0x134/0x160)
> [ 6961.408137] [<c0140d34>] (kthread) from [<c0100114>] (ret_from_fork+0x14/0x20)
> [ 6961.415377] Exception stack(0xcdc09fb0 to 0xcdc09ff8)
> [ 6961.420448] 9fa0: 00000000 00000000 00000000 00000000
> [ 6961.428647] 9fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
> [ 6961.436845] 9fe0: 00000000 00000000 00000000 00000000 00000013 00000000
> [ 6961.443488] Code: e4808004 e480e004 e8bd01e0 e1b02f82 (14d13001)
>
> where dcp_chan_thread_aes+0x220 is the line
>
> memcpy(in_buf + actx->fill, src_buf, clen);
>
> in mxs_dcp_aes_block_crypt. I also tried with the following patch
> instead of the one included in this series:
>
> ---
> diff --git a/drivers/crypto/mxs-dcp.c b/drivers/crypto/mxs-dcp.c
> index f397cc5bf102..54fd24ba1261 100644
> --- a/drivers/crypto/mxs-dcp.c
> +++ b/drivers/crypto/mxs-dcp.c
> @@ -367,6 +367,7 @@ static int mxs_dcp_aes_block_crypt(struct crypto_async_request *arq)
> last_out_len = actx->fill;
> while (dst && actx->fill) {
> if (!split) {
> + kmap(sg_page(dst));
> dst_buf = sg_virt(dst);
> dst_off = 0;
> }
> @@ -379,6 +380,7 @@ static int mxs_dcp_aes_block_crypt(struct crypto_async_request *arq)
> actx->fill -= rem;
>
> if (dst_off == sg_dma_len(dst)) {
> + kunmap(sg_page(dst));
> dst = sg_next(dst);
> split = 0;
> } else {
> --
>
> but got the same oops. Unfortunately, I don't have the time to
> investigate this oops as well. I'd appreciate if anyone else using this
> device could look into this and see if they encounter the same errors.
>
> [1] https://github.com/smuellerDD/libkcapi/blob/master/test/kcapi-dgst-test.sh
>
> Changes in v2:
> - Fix warning when taking the minimum of a u32 and a size_t
> - Use sg_pcopy_from_buffer to properly deal with partial reads.
>
> Sean Anderson (2):
> crypto: mxs-dcp: Check for DMA mapping errors
> crypto: mxs_dcp: Use sg_mapping_iter to copy data
>
> drivers/crypto/mxs-dcp.c | 81 ++++++++++++++++++++++------------------
> 1 file changed, 44 insertions(+), 37 deletions(-)
All applied. Thanks.
--
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
