Re: fbconsole needs more parameter validations.

2020-07-11 Thread Tetsuo Handa
On 2020/07/11 15:16, Tetsuo Handa wrote: > On 2020/07/10 19:56, Greg Kroah-Hartman wrote: >> Where is the over/underflow happening here when we set a size to be so >> small? We should bound the size somewhere, and as you show, that's not >> really working properly, right? > > It is bit_clear_marg

Re: fbconsole needs more parameter validations.

2020-07-10 Thread Tetsuo Handa
On 2020/07/10 19:56, Greg Kroah-Hartman wrote: > Where is the over/underflow happening here when we set a size to be so > small? We should bound the size somewhere, and as you show, that's not > really working properly, right? It is bit_clear_margins() where integer underflow is happening (429496

Re: fbconsole needs more parameter validations.

2020-07-10 Thread Greg Kroah-Hartman
On Fri, Jul 10, 2020 at 02:56:58PM +0900, Tetsuo Handa wrote: > Hello. > > While trying to debug > https://syzkaller.appspot.com/bug?extid=017265e8553724e514e8 , > I noticed that a crash can happen without opening /dev/ttyXX . > > For example, while a driver which syzbot is reporting accepts scr