crypto: authenc - Fix cryptlen calculation

This patch (applied against 2.6.34) fixes the calculation of the
length of the ABLKCIPHER decrypt request ("cryptlen") after an
asynchronous hash request has been completed in the AUTHENC interface.

Signed-off-by: Shikhar Khattar <shikhark@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/crypto/authenc.c b/crypto/authenc.c
index 05eb32e0d9495015f1a7970a079f882d0762a5c7..b9884ee0adb679e2dd77fa674915b586952cfc37 100644 (file)
--- a/crypto/authenc.c
+++ b/crypto/authenc.c
@@ -181,6 +181,7 @@ static void authenc_verify_ahash_update_done(struct crypto_async_request *areq,
        struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
        struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
        struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
+       unsigned int cryptlen = req->cryptlen;
 
        if (err)
                goto out;
@@ -196,6 +197,7 @@ static void authenc_verify_ahash_update_done(struct crypto_async_request *areq,
                goto out;
 
        authsize = crypto_aead_authsize(authenc);
+       cryptlen -= authsize;
        ihash = ahreq->result + authsize;
        scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
                                 authsize, 0);
@@ -209,7 +211,7 @@ static void authenc_verify_ahash_update_done(struct crypto_async_request *areq,
        ablkcipher_request_set_callback(abreq, aead_request_flags(req),
                                        req->base.complete, req->base.data);
        ablkcipher_request_set_crypt(abreq, req->src, req->dst,
-                                    req->cryptlen, req->iv);
+                                    cryptlen, req->iv);
 
        err = crypto_ablkcipher_decrypt(abreq);
 
@@ -228,11 +230,13 @@ static void authenc_verify_ahash_done(struct crypto_async_request *areq,
        struct crypto_authenc_ctx *ctx = crypto_aead_ctx(authenc);
        struct authenc_request_ctx *areq_ctx = aead_request_ctx(req);
        struct ahash_request *ahreq = (void *)(areq_ctx->tail + ctx->reqoff);
+       unsigned int cryptlen = req->cryptlen;
 
        if (err)
                goto out;
 
        authsize = crypto_aead_authsize(authenc);
+       cryptlen -= authsize;
        ihash = ahreq->result + authsize;
        scatterwalk_map_and_copy(ihash, areq_ctx->sg, areq_ctx->cryptlen,
                                 authsize, 0);
@@ -246,7 +250,7 @@ static void authenc_verify_ahash_done(struct crypto_async_request *areq,
        ablkcipher_request_set_callback(abreq, aead_request_flags(req),
                                        req->base.complete, req->base.data);
        ablkcipher_request_set_crypt(abreq, req->src, req->dst,
-                                    req->cryptlen, req->iv);
+                                    cryptlen, req->iv);
 
        err = crypto_ablkcipher_decrypt(abreq);