2022-05-12 17:30:07

by Tzung-Bi Shih

Subject: [PATCH 5/6] platform/chrome: cros_ec_i2c: drop BUG_ON() in cros_ec_pkt_xfer_i2c()

It is overkill to crash the kernel if the given message is oversize.

Drop the BUG_ON() and return -EINVAL instead.

Signed-off-by: Tzung-Bi Shih <[email protected]>
---
drivers/platform/chrome/cros_ec_i2c.c | 10 ++++++++--
1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/drivers/platform/chrome/cros_ec_i2c.c b/drivers/platform/chrome/cros_ec_i2c.c
index a4f305f1eb0e..9f5b95763173 100644
--- a/drivers/platform/chrome/cros_ec_i2c.c
+++ b/drivers/platform/chrome/cros_ec_i2c.c
@@ -72,13 +72,19 @@ static int cros_ec_pkt_xfer_i2c(struct cros_ec_device *ec_dev,
i2c_msg[1].flags = I2C_M_RD;

packet_len = msg->insize + response_header_size;
- BUG_ON(packet_len > ec_dev->din_size);
+ if (packet_len > ec_dev->din_size) {
+ ret = -EINVAL;
+ goto done;
+ }
in_buf = ec_dev->din;
i2c_msg[1].len = packet_len;
i2c_msg[1].buf = (char *) in_buf;

packet_len = msg->outsize + request_header_size;
- BUG_ON(packet_len > ec_dev->dout_size);
+ if (packet_len > ec_dev->dout_size) {
+ ret = -EINVAL;
+ goto done;
+ }
out_buf = ec_dev->dout;
i2c_msg[0].len = packet_len;
i2c_msg[0].buf = (char *) out_buf;
--
2.36.0.512.ge40c2bad7a-goog

2022-05-13 14:17:29

by Guenter Roeck

Subject: Re: [PATCH 5/6] platform/chrome: cros_ec_i2c: drop BUG_ON() in cros_ec_pkt_xfer_i2c()

On Thu, May 12, 2022 at 1:36 AM Tzung-Bi Shih <[email protected]> wrote:
>
> It is overkill to crash the kernel if the given message is oversize.
>
> Drop the BUG_ON() and return -EINVAL instead.
>
> Signed-off-by: Tzung-Bi Shih <[email protected]>

Reviewed-by: Guenter Roeck <[email protected]>

> ---
> drivers/platform/chrome/cros_ec_i2c.c | 10 ++++++++--
> 1 file changed, 8 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/platform/chrome/cros_ec_i2c.c b/drivers/platform/chrome/cros_ec_i2c.c
> index a4f305f1eb0e..9f5b95763173 100644
> --- a/drivers/platform/chrome/cros_ec_i2c.c
> +++ b/drivers/platform/chrome/cros_ec_i2c.c
> @@ -72,13 +72,19 @@ static int cros_ec_pkt_xfer_i2c(struct cros_ec_device *ec_dev,
> i2c_msg[1].flags = I2C_M_RD;
>
> packet_len = msg->insize + response_header_size;
> - BUG_ON(packet_len > ec_dev->din_size);
> + if (packet_len > ec_dev->din_size) {
> + ret = -EINVAL;
> + goto done;
> + }
> in_buf = ec_dev->din;
> i2c_msg[1].len = packet_len;
> i2c_msg[1].buf = (char *) in_buf;
>
> packet_len = msg->outsize + request_header_size;
> - BUG_ON(packet_len > ec_dev->dout_size);
> + if (packet_len > ec_dev->dout_size) {
> + ret = -EINVAL;
> + goto done;
> + }
> out_buf = ec_dev->dout;
> i2c_msg[0].len = packet_len;
> i2c_msg[0].buf = (char *) out_buf;
> --
> 2.36.0.512.ge40c2bad7a-goog
>