Re: [PATCH -next] platform/chrome: Fix off-by-one error in wilco_ec/debugfs.c
From: Enric Balletbo i Serra
Date: Thu Feb 21 2019 - 02:58:25 EST
Hi,
On 20/2/19 23:15, Nick Crews wrote:
> Hi Enric,
>
> On Wed, Feb 20, 2019 at 3:06 PM Enric Balletbo i Serra
> <enric.balletbo@xxxxxxxxxxxxx> wrote:
>>
>> Hi Nick,
>>
>> Thanks for the patch.
>>
>> On 20/2/19 22:58, Nick Crews wrote:
>>> Before, in debugfs.c it was possible to supply only the message type,
>>> and not supply any other arguments when sending raw commands. However,
>>> this is never used by the EC, and it led to an underflow error. Now,
>>> just don't allow too short of a command, we will never need
>>> that anyways.
>>>
>>> Fixes: 46c7fd06f8c9 ("platform/chrome: wilco_ec: Add support for raw commands in debugfs")
>>
>> As this is -next material I'd like to squash the fix if you don't mind.
>
>
> Please do. Fixing something after it's already in the tree was a new
> process for me,
> so I tried to copy other people's examples. Please let me know
> if there's anything else I should do something different next time.
>
Squashed and pushed for 5.1
Thanks,
Enric
> Nick
>
>>
>> -- Enric
>>
>>> Signed-off-by: Nick Crews <ncrews@xxxxxxxxxxxx>
>>> ---
>>> drivers/platform/chrome/wilco_ec/debugfs.c | 6 +++---
>>> 1 file changed, 3 insertions(+), 3 deletions(-)
>>>
>>> diff --git a/drivers/platform/chrome/wilco_ec/debugfs.c b/drivers/platform/chrome/wilco_ec/debugfs.c
>>> index 46ff3b6c46c7..c090db2cd5be 100644
>>> --- a/drivers/platform/chrome/wilco_ec/debugfs.c
>>> +++ b/drivers/platform/chrome/wilco_ec/debugfs.c
>>> @@ -136,8 +136,8 @@ static ssize_t raw_write(struct file *file, const char __user *user_buf,
>>> ret = parse_hex_sentence(buf, kcount, request_data, TYPE_AND_DATA_SIZE);
>>> if (ret < 0)
>>> return ret;
>>> - /* Need at least two bytes for message type */
>>> - if (ret < 2)
>>> + /* Need at least two bytes for message type and one for command */
>>> + if (ret < 3)
>>> return -EINVAL;
>>>
>>> /* Clear response data buffer */
>>> @@ -145,7 +145,7 @@ static ssize_t raw_write(struct file *file, const char __user *user_buf,
>>>
>>> msg.type = request_data[0] << 8 | request_data[1];
>>> msg.flags = WILCO_EC_FLAG_RAW;
>>> - msg.command = ret > 2 ? request_data[2] : 0;
>>> + msg.command = request_data[2];
>>> msg.request_data = ret > 3 ? request_data + 3 : 0;
>>> msg.request_size = ret - 3;
>>> msg.response_data = debug_info->raw_data;
>>>