diff options
| author | Andrzej Zaborowski <andrew.zaborowski@intel.com> | 2015-12-12 08:03:51 +0300 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2015-12-22 15:43:24 +0300 |
| commit | 5319216dcfee14886abb2b7090e8fcf2e2d8a611 (patch) | |
| tree | 16befddf660d00d6aea8c5c9acc4061c61e982ce /crypto | |
| parent | 16f080aaadcb912c9a47c8603a38ccad87da38ea (diff) | |
| download | linux-5319216dcfee14886abb2b7090e8fcf2e2d8a611.tar.xz | |
crypto: rsa-pkcs1pad - don't allocate buffer on stack
Avoid the s390 compile "warning: 'pkcs1pad_encrypt_sign_complete'
uses dynamic stack allocation" reported by kbuild test robot. Don't
use a flat zero-filled buffer, instead zero the contents of the SGL.
Signed-off-by: Andrew Zaborowski <andrew.zaborowski@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'crypto')
| -rw-r--r-- | crypto/rsa-pkcs1pad.c | 27 |
1 files changed, 19 insertions, 8 deletions
diff --git a/crypto/rsa-pkcs1pad.c b/crypto/rsa-pkcs1pad.c index accc67d16686..50f5c97e1087 100644 --- a/crypto/rsa-pkcs1pad.c +++ b/crypto/rsa-pkcs1pad.c @@ -110,21 +110,32 @@ static int pkcs1pad_encrypt_sign_complete(struct akcipher_request *req, int err) struct crypto_akcipher *tfm = crypto_akcipher_reqtfm(req); struct pkcs1pad_ctx *ctx = akcipher_tfm_ctx(tfm); struct pkcs1pad_request *req_ctx = akcipher_request_ctx(req); - uint8_t zeros[ctx->key_size - req_ctx->child_req.dst_len]; + size_t pad_len = ctx->key_size - req_ctx->child_req.dst_len; + size_t chunk_len, pad_left; + struct sg_mapping_iter miter; if (!err) { - if (req_ctx->child_req.dst_len < ctx->key_size) { - memset(zeros, 0, sizeof(zeros)); - sg_copy_from_buffer(req->dst, - sg_nents_for_len(req->dst, - sizeof(zeros)), - zeros, sizeof(zeros)); + if (pad_len) { + sg_miter_start(&miter, req->dst, + sg_nents_for_len(req->dst, pad_len), + SG_MITER_ATOMIC | SG_MITER_TO_SG); + + pad_left = pad_len; + while (pad_left) { + sg_miter_next(&miter); + + chunk_len = min(miter.length, pad_left); + memset(miter.addr, 0, chunk_len); + pad_left -= chunk_len; + } + + sg_miter_stop(&miter); } sg_pcopy_from_buffer(req->dst, sg_nents_for_len(req->dst, ctx->key_size), req_ctx->out_buf, req_ctx->child_req.dst_len, - sizeof(zeros)); + pad_len); } req->dst_len = ctx->key_size; |