Re: [Outreachy kernel] [PATCH v2] staging: android: Replace strcpy with strlcpy

[Julia Lawall]

On Sun, 12 Mar 2017, simran singhal wrote:

> Replace strcpy with strlcpy as strcpy does not check for buffer
> overflow.
> This is found using Flawfinder.
>
> Signed-off-by: simran singhal <singhalsimran0@xxxxxxxxx>
> ---
>
>  v2:
>    -Correcting the place of the parenthesis
>
>  drivers/staging/android/ashmem.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/staging/android/ashmem.c b/drivers/staging/android/ashmem.c
> index 7cbad0d..eb2f4ef 100644
> --- a/drivers/staging/android/ashmem.c
> +++ b/drivers/staging/android/ashmem.c
> @@ -548,7 +548,8 @@ static int set_name(struct ashmem_area *asma, void __user *name)
>  	if (unlikely(asma->file))
>  		ret = -EINVAL;
>  	else
> -		strcpy(asma->name + ASHMEM_NAME_PREFIX_LEN, local_name);
> +		strlcpy(asma->name + ASHMEM_NAME_PREFIX_LEN, local_name,
> +			sizeof(asma->name + ASHMEM_NAME_PREFIX_LEN));

This appears to be the old patch.

Actually, looking closer, I don't think this is right at all.  There seems
to be a goal of leaving some space at the beginning of asma->name.  So the
amount of space available for local_name would be computed using a
subtraction, not an addition.

julia

>
>  	mutex_unlock(&ashmem_mutex);
>  	return ret;
> --
> 2.7.4
>
> --
> You received this message because you are subscribed to the Google Groups "outreachy-kernel" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to outreachy-kernel+unsubscribe@xxxxxxxxxxxxxxxxx
> To post to this group, send email to outreachy-kernel@xxxxxxxxxxxxxxxxx
> To view this discussion on the web visit https://groups.google.com/d/msgid/outreachy-kernel/20170311211725.GA12884%40singhal-Inspiron-5558.
> For more options, visit https://groups.google.com/d/optout.
>