linux-kernel - Re: [PATCH 3/6] platform/chrome: cros_ec_proto: drop BUG_ON() in cros_ec_prepare

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 12 May 2022 08:10:38 -0700
From:   Guenter Roeck <groeck@...gle.com>
To:     Tzung-Bi Shih <tzungbi@...nel.org>
Cc:     Benson Leung <bleung@...omium.org>,
        Guenter Roeck <groeck@...omium.org>,
        chrome-platform@...ts.linux.dev,
        linux-kernel <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 3/6] platform/chrome: cros_ec_proto: drop BUG_ON() in cros_ec_prepare_tx()

On Thu, May 12, 2022 at 1:36 AM Tzung-Bi Shih <tzungbi@...nel.org> 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 <tzungbi@...nel.org>

Reviewed-by: Guenter Roeck <groeck@...omium.org>

> ---
>  drivers/platform/chrome/cros_ec_proto.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/platform/chrome/cros_ec_proto.c b/drivers/platform/chrome/cros_ec_proto.c
> index 2d6d3fbfa905..9ce3374846ff 100644
> --- a/drivers/platform/chrome/cros_ec_proto.c
> +++ b/drivers/platform/chrome/cros_ec_proto.c
> @@ -60,7 +60,8 @@ static int prepare_packet(struct cros_ec_device *ec_dev,
>         int i;
>         u8 csum = 0;
>
> -       BUG_ON(msg->outsize + sizeof(*request) > ec_dev->dout_size);
> +       if (msg->outsize + sizeof(*request) > ec_dev->dout_size)
> +               return -EINVAL;
>
>         out = ec_dev->dout;
>         request = (struct ec_host_request *)out;
> @@ -176,7 +177,9 @@ int cros_ec_prepare_tx(struct cros_ec_device *ec_dev,
>         if (ec_dev->proto_version > 2)
>                 return prepare_packet(ec_dev, msg);
>
> -       BUG_ON(msg->outsize > EC_PROTO2_MAX_PARAM_SIZE);
> +       if (msg->outsize > EC_PROTO2_MAX_PARAM_SIZE)
> +               return -EINVAL;
> +
>         out = ec_dev->dout;
>         out[0] = EC_CMD_VERSION0 + msg->version;
>         out[1] = msg->command;
> --
> 2.36.0.512.ge40c2bad7a-goog
>