2024-03-16 20:44:25

by Grigory Bazilevich

Subject: [PATCH] usb: typec: anx7411: Fix possible buffer overflow in anx7411_send_msg()

Passing a size argument greater than or equal to MAX_BUF_LEN causes
a buffer overflow when the checksum is written.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Fixes: fe6d8a9c8e64 ("usb: typec: anx7411: Add Analogix PD ANX7411 support")
Signed-off-by: Grigory Bazilevich <[email protected]>
---
drivers/usb/typec/anx7411.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/typec/anx7411.c b/drivers/usb/typec/anx7411.c
index b12a07edc71b..70ba56dfb22b 100644
--- a/drivers/usb/typec/anx7411.c
+++ b/drivers/usb/typec/anx7411.c
@@ -733,7 +733,7 @@ static int anx7411_send_msg(struct anx7411_data *ctx, u8 type, u8 *buf, u8 size)
u8 crc;
int ret;

- size = min_t(u8, size, (u8)MAX_BUF_LEN);
+ size = min_t(u8, size, (u8)(MAX_BUF_LEN - 1));
memcpy(msg->buf, buf, size);
msg->msg_type = type;
/* msg len equals buffer length + msg_type */
--
2.39.2

2024-03-17 07:54:02

by Christophe JAILLET

Subject: Re: [PATCH] usb: typec: anx7411: Fix possible buffer overflow in anx7411_send_msg()

Le 16/03/2024 à 21:33, Grigory Bazilevich a écrit :
> Passing a size argument greater than or equal to MAX_BUF_LEN causes
> a buffer overflow when the checksum is written.
>
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
>
> Fixes: fe6d8a9c8e64 ("usb: typec: anx7411: Add Analogix PD ANX7411 support")
> Signed-off-by: Grigory Bazilevich <[email protected]>
> ---
> drivers/usb/typec/anx7411.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/usb/typec/anx7411.c b/drivers/usb/typec/anx7411.c
> index b12a07edc71b..70ba56dfb22b 100644
> --- a/drivers/usb/typec/anx7411.c
> +++ b/drivers/usb/typec/anx7411.c
> @@ -733,7 +733,7 @@ static int anx7411_send_msg(struct anx7411_data *ctx, u8 type, u8 *buf, u8 size)
> u8 crc;
> int ret;
>
> - size = min_t(u8, size, (u8)MAX_BUF_LEN);
> + size = min_t(u8, size, (u8)(MAX_BUF_LEN - 1));

Hi,

with "min_t(u8, ...", is the casting needed?

CJ

> memcpy(msg->buf, buf, size);
> msg->msg_type = type;
> /* msg len equals buffer length + msg_type */

2024-03-19 06:57:40

by Xin Ji

Subject: RE: [PATCH] usb: typec: anx7411: Fix possible buffer overflow in anx7411_send_msg()

Hi mrfoxygmfr, thanks for the fixing.

Reviewed-by: Xin Ji <[email protected]>

> -----Original Message-----
> From: [email protected] <[email protected]> On Behalf Of Grigory
> Bazilevich
> Sent: Sunday, March 17, 2024 4:34 AM
> To: Heikki Krogerus <[email protected]>; Greg Kroah-Hartman
> <[email protected]>; Xin Ji <[email protected]>
> Cc: Grigory Bazilevich <[email protected]>; [email protected]; linux-
> [email protected]; [email protected]
> Subject: [PATCH] usb: typec: anx7411: Fix possible buffer overflow in
> anx7411_send_msg()
>
> CAUTION: This email originated from outside of the organization. Please do not
> click links or open attachments unless you recognize the sender, and know the
> content is safe.
>
>
> Passing a size argument greater than or equal to MAX_BUF_LEN causes a buffer
> overflow when the checksum is written.
>
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
>
> Fixes: fe6d8a9c8e64 ("usb: typec: anx7411: Add Analogix PD ANX7411 support")
> Signed-off-by: Grigory Bazilevich <[email protected]>
> ---
> drivers/usb/typec/anx7411.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/usb/typec/anx7411.c b/drivers/usb/typec/anx7411.c index
> b12a07edc71b..70ba56dfb22b 100644
> --- a/drivers/usb/typec/anx7411.c
> +++ b/drivers/usb/typec/anx7411.c
> @@ -733,7 +733,7 @@ static int anx7411_send_msg(struct anx7411_data *ctx,
> u8 type, u8 *buf, u8 size)
> u8 crc;
> int ret;
>
> - size = min_t(u8, size, (u8)MAX_BUF_LEN);
> + size = min_t(u8, size, (u8)(MAX_BUF_LEN - 1));
> memcpy(msg->buf, buf, size);
> msg->msg_type = type;
> /* msg len equals buffer length + msg_type */
> --
> 2.39.2

2024-03-22 11:02:10

by Heikki Krogerus

Subject: Re: [PATCH] usb: typec: anx7411: Fix possible buffer overflow in anx7411_send_msg()

On Sat, Mar 16, 2024 at 11:33:53PM +0300, Grigory Bazilevich wrote:
> Passing a size argument greater than or equal to MAX_BUF_LEN causes
> a buffer overflow when the checksum is written.
>
> Found by Linux Verification Center (linuxtesting.org) with SVACE.
>
> Fixes: fe6d8a9c8e64 ("usb: typec: anx7411: Add Analogix PD ANX7411 support")
> Signed-off-by: Grigory Bazilevich <[email protected]>

Reviewed-by: Heikki Krogerus <[email protected]>

> ---
> drivers/usb/typec/anx7411.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/usb/typec/anx7411.c b/drivers/usb/typec/anx7411.c
> index b12a07edc71b..70ba56dfb22b 100644
> --- a/drivers/usb/typec/anx7411.c
> +++ b/drivers/usb/typec/anx7411.c
> @@ -733,7 +733,7 @@ static int anx7411_send_msg(struct anx7411_data *ctx, u8 type, u8 *buf, u8 size)
> u8 crc;
> int ret;
>
> - size = min_t(u8, size, (u8)MAX_BUF_LEN);
> + size = min_t(u8, size, (u8)(MAX_BUF_LEN - 1));
> memcpy(msg->buf, buf, size);
> msg->msg_type = type;
> /* msg len equals buffer length + msg_type */
> --
> 2.39.2

--
heikki