[PATCH 5.2 19/21] crypto: talitos - fix hash on SEC1.

From: Greg Kroah-Hartman
Date: Wed Jul 17 2019 - 23:03:52 EST


From: Christophe Leroy <christophe.leroy@xxxxxx>

commit 58cdbc6d2263beb36954408522762bbe73169306 upstream.

On SEC1, hash provides wrong result when performing hashing in several
steps with input data SG list has more than one element. This was
detected with CONFIG_CRYPTO_MANAGER_EXTRA_TESTS:

[ 44.185947] alg: hash: md5-talitos test failed (wrong result) on test vector 6, cfg="random: may_sleep use_finup src_divs=[<reimport>25.88%@+8063, <flush>24.19%@+9588, 28.63%@+16333, <reimport>4.60%@+6756, 16.70%@+16281] dst_divs=[71.61%@alignmask+16361, 14.36%@+7756, 14.3%@+"
[ 44.325122] alg: hash: sha1-talitos test failed (wrong result) on test vector 3, cfg="random: inplace use_final src_divs=[<flush,nosimd>16.56%@+16378, <reimport>52.0%@+16329, 21.42%@alignmask+16380, 10.2%@alignmask+16380] iv_offset=39"
[ 44.493500] alg: hash: sha224-talitos test failed (wrong result) on test vector 4, cfg="random: use_final nosimd src_divs=[<reimport>52.27%@+7401, <reimport>17.34%@+16285, <flush>17.71%@+26, 12.68%@+10644] iv_offset=43"
[ 44.673262] alg: hash: sha256-talitos test failed (wrong result) on test vector 4, cfg="random: may_sleep use_finup src_divs=[<reimport>60.6%@+12790, 17.86%@+1329, <reimport>12.64%@alignmask+16300, 8.29%@+15, 0.40%@+13506, <reimport>0.51%@+16322, <reimport>0.24%@+16339] dst_divs"

This is due to two issues:
- We have an overlap between the buffer used for copying the input
data (SEC1 doesn't do scatter/gather) and the chained descriptor.
- Data copy is wrong when the previous hash left less than one
blocksize of data to hash, implying a complement of the previous
block with a few bytes from the new request.

Fix it by:
- Moving the second descriptor after the buffer, as moving the buffer
after the descriptor would make it more complex for other cipher
operations (AEAD, ABLKCIPHER)
- Skip the bytes taken from the new request to complete the previous
one by moving the SG list forward.

Fixes: 37b5e8897eb5 ("crypto: talitos - chain in buffered data for ahash on SEC1")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/crypto/talitos.c | 69 +++++++++++++++++++++++++++--------------------
1 file changed, 41 insertions(+), 28 deletions(-)

--- a/drivers/crypto/talitos.c
+++ b/drivers/crypto/talitos.c
@@ -321,6 +321,21 @@ int talitos_submit(struct device *dev, i
}
EXPORT_SYMBOL(talitos_submit);

+static __be32 get_request_hdr(struct talitos_request *request, bool is_sec1)
+{
+ struct talitos_edesc *edesc;
+
+ if (!is_sec1)
+ return request->desc->hdr;
+
+ if (!request->desc->next_desc)
+ return request->desc->hdr1;
+
+ edesc = container_of(request->desc, struct talitos_edesc, desc);
+
+ return ((struct talitos_desc *)(edesc->buf + edesc->dma_len))->hdr1;
+}
+
/*
* process what was done, notify callback of error if not
*/
@@ -342,12 +357,7 @@ static void flush_channel(struct device

/* descriptors with their done bits set don't get the error */
rmb();
- if (!is_sec1)
- hdr = request->desc->hdr;
- else if (request->desc->next_desc)
- hdr = (request->desc + 1)->hdr1;
- else
- hdr = request->desc->hdr1;
+ hdr = get_request_hdr(request, is_sec1);

if ((hdr & DESC_HDR_DONE) == DESC_HDR_DONE)
status = 0;
@@ -477,8 +487,14 @@ static u32 current_desc_hdr(struct devic
}
}

- if (priv->chan[ch].fifo[iter].desc->next_desc == cur_desc)
- return (priv->chan[ch].fifo[iter].desc + 1)->hdr;
+ if (priv->chan[ch].fifo[iter].desc->next_desc == cur_desc) {
+ struct talitos_edesc *edesc;
+
+ edesc = container_of(priv->chan[ch].fifo[iter].desc,
+ struct talitos_edesc, desc);
+ return ((struct talitos_desc *)
+ (edesc->buf + edesc->dma_len))->hdr;
+ }

return priv->chan[ch].fifo[iter].desc->hdr;
}
@@ -1436,15 +1452,11 @@ static struct talitos_edesc *talitos_ede
edesc->dst_nents = dst_nents;
edesc->iv_dma = iv_dma;
edesc->dma_len = dma_len;
- if (dma_len) {
- void *addr = &edesc->link_tbl[0];
-
- if (is_sec1 && !dst)
- addr += sizeof(struct talitos_desc);
- edesc->dma_link_tbl = dma_map_single(dev, addr,
+ if (dma_len)
+ edesc->dma_link_tbl = dma_map_single(dev, &edesc->link_tbl[0],
edesc->dma_len,
DMA_BIDIRECTIONAL);
- }
+
return edesc;
}

@@ -1729,14 +1741,16 @@ static void common_nonsnoop_hash_unmap(s
struct talitos_private *priv = dev_get_drvdata(dev);
bool is_sec1 = has_ftr_sec1(priv);
struct talitos_desc *desc = &edesc->desc;
- struct talitos_desc *desc2 = desc + 1;
+ struct talitos_desc *desc2 = (struct talitos_desc *)
+ (edesc->buf + edesc->dma_len);

unmap_single_talitos_ptr(dev, &edesc->desc.ptr[5], DMA_FROM_DEVICE);
if (desc->next_desc &&
desc->ptr[5].ptr != desc2->ptr[5].ptr)
unmap_single_talitos_ptr(dev, &desc2->ptr[5], DMA_FROM_DEVICE);

- talitos_sg_unmap(dev, edesc, req_ctx->psrc, NULL, 0, 0);
+ if (req_ctx->psrc)
+ talitos_sg_unmap(dev, edesc, req_ctx->psrc, NULL, 0, 0);

/* When using hashctx-in, must unmap it. */
if (from_talitos_ptr_len(&edesc->desc.ptr[1], is_sec1))
@@ -1803,7 +1817,6 @@ static void talitos_handle_buggy_hash(st

static int common_nonsnoop_hash(struct talitos_edesc *edesc,
struct ahash_request *areq, unsigned int length,
- unsigned int offset,
void (*callback) (struct device *dev,
struct talitos_desc *desc,
void *context, int error))
@@ -1842,9 +1855,7 @@ static int common_nonsnoop_hash(struct t

sg_count = edesc->src_nents ?: 1;
if (is_sec1 && sg_count > 1)
- sg_pcopy_to_buffer(req_ctx->psrc, sg_count,
- edesc->buf + sizeof(struct talitos_desc),
- length, req_ctx->nbuf);
+ sg_copy_to_buffer(req_ctx->psrc, sg_count, edesc->buf, length);
else if (length)
sg_count = dma_map_sg(dev, req_ctx->psrc, sg_count,
DMA_TO_DEVICE);
@@ -1857,7 +1868,7 @@ static int common_nonsnoop_hash(struct t
DMA_TO_DEVICE);
} else {
sg_count = talitos_sg_map(dev, req_ctx->psrc, length, edesc,
- &desc->ptr[3], sg_count, offset, 0);
+ &desc->ptr[3], sg_count, 0, 0);
if (sg_count > 1)
sync_needed = true;
}
@@ -1881,7 +1892,8 @@ static int common_nonsnoop_hash(struct t
talitos_handle_buggy_hash(ctx, edesc, &desc->ptr[3]);

if (is_sec1 && req_ctx->nbuf && length) {
- struct talitos_desc *desc2 = desc + 1;
+ struct talitos_desc *desc2 = (struct talitos_desc *)
+ (edesc->buf + edesc->dma_len);
dma_addr_t next_desc;

memset(desc2, 0, sizeof(*desc2));
@@ -1902,7 +1914,7 @@ static int common_nonsnoop_hash(struct t
DMA_TO_DEVICE);
copy_talitos_ptr(&desc2->ptr[2], &desc->ptr[2], is_sec1);
sg_count = talitos_sg_map(dev, req_ctx->psrc, length, edesc,
- &desc2->ptr[3], sg_count, offset, 0);
+ &desc2->ptr[3], sg_count, 0, 0);
if (sg_count > 1)
sync_needed = true;
copy_talitos_ptr(&desc2->ptr[5], &desc->ptr[5], is_sec1);
@@ -2013,7 +2025,6 @@ static int ahash_process_req(struct ahas
struct device *dev = ctx->dev;
struct talitos_private *priv = dev_get_drvdata(dev);
bool is_sec1 = has_ftr_sec1(priv);
- int offset = 0;
u8 *ctx_buf = req_ctx->buf[req_ctx->buf_idx];

if (!req_ctx->last && (nbytes + req_ctx->nbuf <= blocksize)) {
@@ -2053,6 +2064,8 @@ static int ahash_process_req(struct ahas
sg_chain(req_ctx->bufsl, 2, areq->src);
req_ctx->psrc = req_ctx->bufsl;
} else if (is_sec1 && req_ctx->nbuf && req_ctx->nbuf < blocksize) {
+ int offset;
+
if (nbytes_to_hash > blocksize)
offset = blocksize - req_ctx->nbuf;
else
@@ -2065,7 +2078,8 @@ static int ahash_process_req(struct ahas
sg_copy_to_buffer(areq->src, nents,
ctx_buf + req_ctx->nbuf, offset);
req_ctx->nbuf += offset;
- req_ctx->psrc = areq->src;
+ req_ctx->psrc = scatterwalk_ffwd(req_ctx->bufsl, areq->src,
+ offset);
} else
req_ctx->psrc = areq->src;

@@ -2105,8 +2119,7 @@ static int ahash_process_req(struct ahas
if (ctx->keylen && (req_ctx->first || req_ctx->last))
edesc->desc.hdr |= DESC_HDR_MODE0_MDEU_HMAC;

- return common_nonsnoop_hash(edesc, areq, nbytes_to_hash, offset,
- ahash_done);
+ return common_nonsnoop_hash(edesc, areq, nbytes_to_hash, ahash_done);
}

static int ahash_update(struct ahash_request *areq)