Re: linux-next: manual merge of the userns tree with the arm tree

From: Eric W. Biederman
Date: Sun May 27 2018 - 14:30:58 EST


Mark Brown <broonie@xxxxxxxxxx> writes:

> Hi Eric,
>
> Yesterday's linux-next merge of the userns tree got a conflict in:
>
> arch/arm/mm/fault.c
>
> between commit:
>
> 8d9267cedb9e1d8edb8 ("ARM: spectre-v2: harden user aborts in kernel space")
>
> from the arm tree and commit:
>
> 3eb0f5193b497083391 ("signal: Ensure every siginfo we send has all bits initialized")
>
> from the userns tree.
>
> I fixed it up (see below) and can carry the fix as necessary. This
> is now fixed as far as linux-next is concerned, but any non trivial
> conflicts should be mentioned to your upstream maintainer when your tree
> is submitted for merging. You may also want to consider cooperating
> with the maintainer of the conflicting tree to minimise any particularly
> complex conflicts.

Mark. Did you get a bounce from this email?

I saw this when perusing lkml but I did not receive a copy of this
directly to myself.

Eric

> diff --cc arch/arm/mm/fault.c
> index 3b1ba003c4f9,32034543f49c..000000000000
> --- a/arch/arm/mm/fault.c
> +++ b/arch/arm/mm/fault.c
> @@@ -163,9 -163,8 +163,11 @@@ __do_user_fault(struct task_struct *tsk
> {
> struct siginfo si;
>
> + clear_siginfo(&si);
> +
> + if (addr > TASK_SIZE)
> + harden_branch_predictor();
> +
> #ifdef CONFIG_DEBUG_USER
> if (((user_debug & UDBG_SEGV) && (sig == SIGSEGV)) ||
> ((user_debug & UDBG_BUS) && (sig == SIGBUS))) {