2024-01-30 11:28:05

by zhenwei pi

Subject: [PATCH] crypto: virtio/akcipher - Fix stack overflow on memcpy

sizeof(struct virtio_crypto_akcipher_session_para) is less than
sizeof(struct virtio_crypto_op_ctrl_req::u), copying more bytes from
stack variable leads stack overflow. Clang reports this issue by
commands:
make -j CC=clang-14 mrproper >/dev/null 2>&1
make -j O=/tmp/crypto-build CC=clang-14 allmodconfig >/dev/null 2>&1
make -j O=/tmp/crypto-build W=1 CC=clang-14 drivers/crypto/virtio/
virtio_crypto_akcipher_algs.o

Fixes: 59ca6c93387d ("virtio-crypto: implement RSA algorithm")
Link: https://lore.kernel.org/all/[email protected]/
Signed-off-by: zhenwei pi <[email protected]>
---
drivers/crypto/virtio/virtio_crypto_akcipher_algs.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c b/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
index 2621ff8a9376..de53eddf6796 100644
--- a/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
+++ b/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
@@ -104,7 +104,8 @@ static void virtio_crypto_dataq_akcipher_callback(struct virtio_crypto_request *
}

static int virtio_crypto_alg_akcipher_init_session(struct virtio_crypto_akcipher_ctx *ctx,
- struct virtio_crypto_ctrl_header *header, void *para,
+ struct virtio_crypto_ctrl_header *header,
+ struct virtio_crypto_akcipher_session_para *para,
const uint8_t *key, unsigned int keylen)
{
struct scatterlist outhdr_sg, key_sg, inhdr_sg, *sgs[3];
@@ -128,7 +129,7 @@ static int virtio_crypto_alg_akcipher_init_session(struct virtio_crypto_akcipher

ctrl = &vc_ctrl_req->ctrl;
memcpy(&ctrl->header, header, sizeof(ctrl->header));
- memcpy(&ctrl->u, para, sizeof(ctrl->u));
+ memcpy(&ctrl->u.akcipher_create_session.para, para, sizeof(*para));
input = &vc_ctrl_req->input;
input->status = cpu_to_le32(VIRTIO_CRYPTO_ERR);

--
2.34.1

2024-01-31 19:10:21

by Nathan Chancellor

Subject: Re: [PATCH] crypto: virtio/akcipher - Fix stack overflow on memcpy

On Tue, Jan 30, 2024 at 07:27:40PM +0800, zhenwei pi wrote:
> sizeof(struct virtio_crypto_akcipher_session_para) is less than
> sizeof(struct virtio_crypto_op_ctrl_req::u), copying more bytes from
> stack variable leads stack overflow. Clang reports this issue by
> commands:
> make -j CC=clang-14 mrproper >/dev/null 2>&1
> make -j O=/tmp/crypto-build CC=clang-14 allmodconfig >/dev/null 2>&1
> make -j O=/tmp/crypto-build W=1 CC=clang-14 drivers/crypto/virtio/
> virtio_crypto_akcipher_algs.o
>
> Fixes: 59ca6c93387d ("virtio-crypto: implement RSA algorithm")
> Link: https://lore.kernel.org/all/[email protected]/
> Signed-off-by: zhenwei pi <[email protected]>

I can confirm this resolves the warning for me as well.

Tested-by: Nathan Chancellor <[email protected]> # build

I suspect Guenter should have a formal Reported-by tag. Should this be
CC'd for stable@ as well?

Cheers,
Nathan

> ---
> drivers/crypto/virtio/virtio_crypto_akcipher_algs.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c b/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
> index 2621ff8a9376..de53eddf6796 100644
> --- a/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
> +++ b/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
> @@ -104,7 +104,8 @@ static void virtio_crypto_dataq_akcipher_callback(struct virtio_crypto_request *
> }
>
> static int virtio_crypto_alg_akcipher_init_session(struct virtio_crypto_akcipher_ctx *ctx,
> - struct virtio_crypto_ctrl_header *header, void *para,
> + struct virtio_crypto_ctrl_header *header,
> + struct virtio_crypto_akcipher_session_para *para,
> const uint8_t *key, unsigned int keylen)
> {
> struct scatterlist outhdr_sg, key_sg, inhdr_sg, *sgs[3];
> @@ -128,7 +129,7 @@ static int virtio_crypto_alg_akcipher_init_session(struct virtio_crypto_akcipher
>
> ctrl = &vc_ctrl_req->ctrl;
> memcpy(&ctrl->header, header, sizeof(ctrl->header));
> - memcpy(&ctrl->u, para, sizeof(ctrl->u));
> + memcpy(&ctrl->u.akcipher_create_session.para, para, sizeof(*para));
> input = &vc_ctrl_req->input;
> input->status = cpu_to_le32(VIRTIO_CRYPTO_ERR);
>
> --
> 2.34.1
>

2024-01-31 22:37:07

by Michael S. Tsirkin

Subject: Re: [PATCH] crypto: virtio/akcipher - Fix stack overflow on memcpy

On Tue, Jan 30, 2024 at 07:27:40PM +0800, zhenwei pi wrote:
> sizeof(struct virtio_crypto_akcipher_session_para) is less than
> sizeof(struct virtio_crypto_op_ctrl_req::u), copying more bytes from
> stack variable leads stack overflow. Clang reports this issue by
> commands:
> make -j CC=clang-14 mrproper >/dev/null 2>&1
> make -j O=/tmp/crypto-build CC=clang-14 allmodconfig >/dev/null 2>&1
> make -j O=/tmp/crypto-build W=1 CC=clang-14 drivers/crypto/virtio/
> virtio_crypto_akcipher_algs.o
>
> Fixes: 59ca6c93387d ("virtio-crypto: implement RSA algorithm")
> Link: https://lore.kernel.org/all/[email protected]/
> Signed-off-by: zhenwei pi <[email protected]>

Cc: [email protected]
Acked-by: Michael S. Tsirkin <[email protected]>



> ---
> drivers/crypto/virtio/virtio_crypto_akcipher_algs.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c b/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
> index 2621ff8a9376..de53eddf6796 100644
> --- a/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
> +++ b/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
> @@ -104,7 +104,8 @@ static void virtio_crypto_dataq_akcipher_callback(struct virtio_crypto_request *
> }
>
> static int virtio_crypto_alg_akcipher_init_session(struct virtio_crypto_akcipher_ctx *ctx,
> - struct virtio_crypto_ctrl_header *header, void *para,
> + struct virtio_crypto_ctrl_header *header,
> + struct virtio_crypto_akcipher_session_para *para,
> const uint8_t *key, unsigned int keylen)
> {
> struct scatterlist outhdr_sg, key_sg, inhdr_sg, *sgs[3];
> @@ -128,7 +129,7 @@ static int virtio_crypto_alg_akcipher_init_session(struct virtio_crypto_akcipher
>
> ctrl = &vc_ctrl_req->ctrl;
> memcpy(&ctrl->header, header, sizeof(ctrl->header));
> - memcpy(&ctrl->u, para, sizeof(ctrl->u));
> + memcpy(&ctrl->u.akcipher_create_session.para, para, sizeof(*para));
> input = &vc_ctrl_req->input;
> input->status = cpu_to_le32(VIRTIO_CRYPTO_ERR);
>
> --
> 2.34.1

2024-02-01 06:04:34

by Jason Wang

Subject: Re: [PATCH] crypto: virtio/akcipher - Fix stack overflow on memcpy

On Tue, Jan 30, 2024 at 7:28 PM zhenwei pi <[email protected]> wrote:
>
> sizeof(struct virtio_crypto_akcipher_session_para) is less than
> sizeof(struct virtio_crypto_op_ctrl_req::u), copying more bytes from
> stack variable leads stack overflow. Clang reports this issue by
> commands:
> make -j CC=clang-14 mrproper >/dev/null 2>&1
> make -j O=/tmp/crypto-build CC=clang-14 allmodconfig >/dev/null 2>&1
> make -j O=/tmp/crypto-build W=1 CC=clang-14 drivers/crypto/virtio/
> virtio_crypto_akcipher_algs.o
>
> Fixes: 59ca6c93387d ("virtio-crypto: implement RSA algorithm")
> Link: https://lore.kernel.org/all/[email protected]/
> Signed-off-by: zhenwei pi <[email protected]>

Acked-by: Jason Wang <[email protected]>

Thanks