On 1/15/20 6:42 AM, Andrey Konovalov wrote:
>> - max_addr = user_addr_max();
>> - src_addr = (unsigned long)untagged_addr(src);
>
> If you end up changing this code, you need to keep the untagged_addr()
> logic, otherwise this breaks arm64 tagged address ABI [1].
It is moot point now,
On Tue, Jan 14, 2020 at 9:08 PM Vineet Gupta wrote:
>
> This came up when switching ARC to word-at-a-time interface and using
> generic/optimized strncpy_from_user
>
> It seems the existing code checks for user buffer/string range multiple
> times and one of tem cn be avoided.
>
> There's an open-
On Tue, Jan 14, 2020 at 01:22:07PM -0800, Linus Torvalds wrote:
> The fact is, copying a string from user space is *very* different from
> copying a fixed number of bytes, and that whole dance with
>
> max_addr = user_addr_max();
>
> is absolutely required and necessary.
>
> You complet
On 1/14/20 1:22 PM, Linus Torvalds wrote:
> On Tue, Jan 14, 2020 at 12:09 PM Vineet Gupta
> wrote:
>>
>> This came up when switching ARC to word-at-a-time interface and using
>> generic/optimized strncpy_from_user
>>
>> It seems the existing code checks for user buffer/string range multiple
>> tim
On Tue, Jan 14, 2020 at 12:09 PM Vineet Gupta
wrote:
>
> This came up when switching ARC to word-at-a-time interface and using
> generic/optimized strncpy_from_user
>
> It seems the existing code checks for user buffer/string range multiple
> times and one of tem cn be avoided.
NO!
DO NOT DO THI
This came up when switching ARC to word-at-a-time interface and using
generic/optimized strncpy_from_user
It seems the existing code checks for user buffer/string range multiple
times and one of tem cn be avoided.
There's an open-coded range check which computes @max off of user_addr_max()
and th
