Re: [PATCH] proc: use vmalloc for our kernel buffer

Josef Bacik
2020-08-13T15:08:48Z

On 8/13/20 10:59 AM, Matthew Wilcox wrote:
> On Thu, Aug 13, 2020 at 10:53:05AM -0400, Josef Bacik wrote:
>> +/**
>> + * vmemdup_user - duplicate memory region from user space and NUL-terminate
>
> vmemdup_user_nul()
>
>> +void *vmemdup_user_nul(const void __user *src, size_t len)
>> +{
>> + void *p;
>> +
>> + p = kvmalloc(len, GFP_USER);
>
> len+1, shirley?
>
>> + if (!p)
>> + return ERR_PTR(-ENOMEM);
>> +
>> + if (copy_from_user(p, src, len)) {
>> + kvfree(p);
>> + return ERR_PTR(-EFAULT);
>> + }
>
> I think you forgot
>
> p[len] = '\0';
>

Sweet lord I need more sleep, my bad. Thanks,

Josef