Re: [Linux-kernel-mentees] [PATCH] firewire: Prevent kernel-infoleak in ioctl_get_info()

From: Peilin Ye
Date: Mon Jul 27 2020 - 11:40:39 EST


On Mon, Jul 27, 2020 at 05:35:12PM +0200, Arnd Bergmann wrote:
> On Mon, Jul 27, 2020 at 5:18 PM Peilin Ye <yepeilin.cs@xxxxxxxxx> wrote:
> >
> > ioctl_get_info() is copying uninitialized stack memory to userspace due to
> > the compiler not initializing holes in statically allocated structures.
> > Fix it by initializing `event` using memset() in fill_bus_reset_event().
> >
> > Cc: stable@xxxxxxxxxxxxxxx
> > Suggested-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> > Suggested-by: Arnd Bergmann <arnd@xxxxxxxx>
> > Signed-off-by: Peilin Ye <yepeilin.cs@xxxxxxxxx>
>
> Acked-by: Arnd Bergmann <arnd@xxxxxxxx>
>
> I would recommend always looking through the git history of the
> file to come up with an appropriate 'Fixes' tag. In this case
>
> $ git log -p --follow drivers/firewire/core-cdev.c
>
> searching for any mention of fill_bus_reset_event leads you to
> commit 344bbc4de14e.
>
> In my ~/.gitconfig I have this alias:
>
> [core]
> abbrev = 12
> [alias]
> fixes = show --format='Fixes: %h (\"%s\")' -s
>
> With something like that, calling 'git fixes 344bbc4de14e' produces
> the line to copy:
>
> Fixes: 344bbc4de14e ("firewire: Generalize get_config_rom to get_info.")

Thank you for the advice! Actually I did all of that (manually...) but
wasn't sure whether I should add it on. I will send a v2 soon, and do so
for future patches.

Thank you,
Peilin Ye