| From d07f951903fa9922c375b8ab1ce81b18a0034e3b Mon Sep 17 00:00:00 2001 |
| From: Herbert Xu <herbert@gondor.apana.org.au> |
| Date: Tue, 28 Nov 2023 14:22:13 +0800 |
| Subject: crypto: s390/aes - Fix buffer overread in CTR mode |
| |
| From: Herbert Xu <herbert@gondor.apana.org.au> |
| |
| commit d07f951903fa9922c375b8ab1ce81b18a0034e3b upstream. |
| |
| When processing the last block, the s390 ctr code will always read |
| a whole block, even if there isn't a whole block of data left. Fix |
| this by using the actual length left and copy it into a buffer first |
| for processing. |
| |
| Fixes: 0200f3ecc196 ("crypto: s390 - add System z hardware support for CTR mode") |
| Cc: <stable@vger.kernel.org> |
| Reported-by: Guangwu Zhang <guazhang@redhat.com> |
| Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> |
| Reviewd-by: Harald Freudenberger <freude@de.ibm.com> |
| Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| arch/s390/crypto/aes_s390.c | 4 +++- |
| arch/s390/crypto/paes_s390.c | 4 +++- |
| 2 files changed, 6 insertions(+), 2 deletions(-) |
| |
| --- a/arch/s390/crypto/aes_s390.c |
| +++ b/arch/s390/crypto/aes_s390.c |
| @@ -601,7 +601,9 @@ static int ctr_aes_crypt(struct skcipher |
| * final block may be < AES_BLOCK_SIZE, copy only nbytes |
| */ |
| if (nbytes) { |
| - cpacf_kmctr(sctx->fc, sctx->key, buf, walk.src.virt.addr, |
| + memset(buf, 0, AES_BLOCK_SIZE); |
| + memcpy(buf, walk.src.virt.addr, nbytes); |
| + cpacf_kmctr(sctx->fc, sctx->key, buf, buf, |
| AES_BLOCK_SIZE, walk.iv); |
| memcpy(walk.dst.virt.addr, buf, nbytes); |
| crypto_inc(walk.iv, AES_BLOCK_SIZE); |
| --- a/arch/s390/crypto/paes_s390.c |
| +++ b/arch/s390/crypto/paes_s390.c |
| @@ -688,9 +688,11 @@ static int ctr_paes_crypt(struct skciphe |
| * final block may be < AES_BLOCK_SIZE, copy only nbytes |
| */ |
| if (nbytes) { |
| + memset(buf, 0, AES_BLOCK_SIZE); |
| + memcpy(buf, walk.src.virt.addr, nbytes); |
| while (1) { |
| if (cpacf_kmctr(ctx->fc, ¶m, buf, |
| - walk.src.virt.addr, AES_BLOCK_SIZE, |
| + buf, AES_BLOCK_SIZE, |
| walk.iv) == AES_BLOCK_SIZE) |
| break; |
| if (__paes_convert_key(ctx)) |
