Re: [PATCH] tty: vt: keyboard: do not copy an extra-byte in copy_to_user

On Sun, Nov 7, 2021 at 1:26 AM Pavel Skripkin [off-list ref] wrote:

On 11/6/21 22:20, Ajay Garg wrote:

quoted

I vote for David's strscpy "fix", as it is simple, and does away with
the dependency on the length of "func_table[kb_func]".

strscpy fix sounds reasonable to me. just to be save in future.

There is only one thing I am wondering about: translation table entries
are set by user using this struct

struct kbsentry {
        unsigned char kb_func;
        unsigned char kb_string[512];
};

it means entries cannot be longer than sizeof(kbsentry::kb_string) - 1
at all. Do we need extra branching with strscpy() or do we need to do
anything else here?

Hi Pavel,

Please see my latest comments in the last reply.

With regards,
Pavel Skripkin