From: Herbert Xu <herbert@gondor.apana.org.au> stable inclusion from stable-v6.6.137 commit d0c4ff6812386880f30bc64c2921299cc4d7b47f category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/14174 CVE: CVE-2026-31431 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit e02494114ebf7c8b42777c6cd6982f113bfdbec7 upstream. When decrypting data that is not in-place (src != dst), there is no need to save the high-order sequence bits in dst as it could simply be re-copied from the source. However, the data to be hashed need to be rearranged accordingly. Reported-by: Taeyang Lee <0wn@theori.io> Fixes: 104880a6b470 ("crypto: authencesn - Convert to new AEAD interface") Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Lu Jialin <lujialin4@huawei.com> --- crypto/authencesn.c | 48 +++++++++++++++++++++++++++------------------ 1 file changed, 29 insertions(+), 19 deletions(-) diff --git a/crypto/authencesn.c b/crypto/authencesn.c index 08ada44022d0..52032b921a0d 100644 --- a/crypto/authencesn.c +++ b/crypto/authencesn.c @@ -212,6 +212,7 @@ static int crypto_authenc_esn_decrypt_tail(struct aead_request *req, crypto_ahash_alignmask(auth) + 1); unsigned int cryptlen = req->cryptlen - authsize; unsigned int assoclen = req->assoclen; + struct scatterlist *src = req->src; struct scatterlist *dst = req->dst; u8 *ihash = ohash + crypto_ahash_digestsize(auth); u32 tmp[2]; @@ -219,23 +220,27 @@ static int crypto_authenc_esn_decrypt_tail(struct aead_request *req, if (!authsize) goto decrypt; - /* Move high-order bits of sequence number back. */ - scatterwalk_map_and_copy(tmp, dst, 4, 4, 0); - scatterwalk_map_and_copy(tmp + 1, dst, assoclen + cryptlen, 4, 0); - scatterwalk_map_and_copy(tmp, dst, 0, 8, 1); + if (src == dst) { + /* Move high-order bits of sequence number back. */ + scatterwalk_map_and_copy(tmp, dst, 4, 4, 0); + scatterwalk_map_and_copy(tmp + 1, dst, assoclen + cryptlen, 4, 0); + scatterwalk_map_and_copy(tmp, dst, 0, 8, 1); + } else + memcpy_sglist(dst, src, assoclen); if (crypto_memneq(ihash, ohash, authsize)) return -EBADMSG; decrypt: - sg_init_table(areq_ctx->dst, 2); + if (src != dst) + src = scatterwalk_ffwd(areq_ctx->src, src, assoclen); dst = scatterwalk_ffwd(areq_ctx->dst, dst, assoclen); skcipher_request_set_tfm(skreq, ctx->enc); skcipher_request_set_callback(skreq, flags, req->base.complete, req->base.data); - skcipher_request_set_crypt(skreq, dst, dst, cryptlen, req->iv); + skcipher_request_set_crypt(skreq, src, dst, cryptlen, req->iv); return crypto_skcipher_decrypt(skreq); } @@ -261,6 +266,7 @@ static int crypto_authenc_esn_decrypt(struct aead_request *req) unsigned int assoclen = req->assoclen; unsigned int cryptlen = req->cryptlen; u8 *ihash = ohash + crypto_ahash_digestsize(auth); + struct scatterlist *src = req->src; struct scatterlist *dst = req->dst; u32 tmp[2]; int err; @@ -268,24 +274,28 @@ static int crypto_authenc_esn_decrypt(struct aead_request *req) if (assoclen < 8) return -EINVAL; - cryptlen -= authsize; - - if (req->src != dst) - memcpy_sglist(dst, req->src, assoclen + cryptlen); + if (!authsize) + goto tail; + cryptlen -= authsize; scatterwalk_map_and_copy(ihash, req->src, assoclen + cryptlen, authsize, 0); - if (!authsize) - goto tail; - /* Move high-order bits of sequence number to the end. */ - scatterwalk_map_and_copy(tmp, dst, 0, 8, 0); - scatterwalk_map_and_copy(tmp, dst, 4, 4, 1); - scatterwalk_map_and_copy(tmp + 1, dst, assoclen + cryptlen, 4, 1); - - sg_init_table(areq_ctx->dst, 2); - dst = scatterwalk_ffwd(areq_ctx->dst, dst, 4); + scatterwalk_map_and_copy(tmp, src, 0, 8, 0); + if (src == dst) { + scatterwalk_map_and_copy(tmp, dst, 4, 4, 1); + scatterwalk_map_and_copy(tmp + 1, dst, assoclen + cryptlen, 4, 1); + dst = scatterwalk_ffwd(areq_ctx->dst, dst, 4); + } else { + scatterwalk_map_and_copy(tmp, dst, 0, 4, 1); + scatterwalk_map_and_copy(tmp + 1, dst, assoclen + cryptlen - 4, 4, 1); + + src = scatterwalk_ffwd(areq_ctx->src, src, 8); + dst = scatterwalk_ffwd(areq_ctx->dst, dst, 4); + memcpy_sglist(dst, src, assoclen + cryptlen - 8); + dst = req->dst; + } ahash_request_set_tfm(ahreq, auth); ahash_request_set_crypt(ahreq, dst, ohash, assoclen + cryptlen); -- 2.34.1