Re: [PATCH] printk: don't unconditionally shortcut print_time()

From: Tetsuo Handa
Date: Mon Dec 03 2018 - 10:00:49 EST


On 2018/12/03 23:14, Petr Mladek wrote:
> Well, IMHO, it does not explain the pagefault above. The copy_to_user()
> could come either from syslog_print() or from syslog_print_all(). They
> both have their own checks that prevent the buf overflow.
>
> The code is tricky but it looks safe now. Is it possible that
> the crash was with some old, still broken, code? Or did you
> add some extra changes that you used to trigger a testing
> scenario?

I think I was using unmodified current linux.git, but I failed to save
the reproducer because I was editing under /tmp directory which does not
create a backup.

Anyway, after this patch, no problem is occurring.