Re: [PATCH AUTOSEL 4.19 111/167] signal/arc: Use force_sig_fault where appropriate

From: Eric W. Biederman
Date: Tue Sep 03 2019 - 12:49:34 EST


Sasha Levin <sashal@xxxxxxxxxx> writes:

> From: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
>
> [ Upstream commit 15773ae938d8d93d982461990bebad6e1d7a1830 ]

To the best of my knowledge this is just a clean up, no changes in
behavior are present.

The only reason I can see to backport this is so that later fixes could
be applied cleanly.

So while I have no objections to this patch being backported I don't see
why you would want to either.

> Acked-by: Vineet Gupta <vgupta@xxxxxxxxxxxx>
> Signed-off-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> ---
> arch/arc/mm/fault.c | 20 +++++---------------
> 1 file changed, 5 insertions(+), 15 deletions(-)
>
> diff --git a/arch/arc/mm/fault.c b/arch/arc/mm/fault.c
> index f28db0b112a30..a0366f9dca051 100644
> --- a/arch/arc/mm/fault.c
> +++ b/arch/arc/mm/fault.c
> @@ -66,14 +66,12 @@ void do_page_fault(unsigned long address, struct pt_regs *regs)
> struct vm_area_struct *vma = NULL;
> struct task_struct *tsk = current;
> struct mm_struct *mm = tsk->mm;
> - siginfo_t info;
> + int si_code;
> int ret;
> vm_fault_t fault;
> int write = regs->ecr_cause & ECR_C_PROTV_STORE; /* ST/EX */
> unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE;
>
> - clear_siginfo(&info);
> -
> /*
> * We fault-in kernel-space virtual memory on-demand. The
> * 'reference' page table is init_mm.pgd.
> @@ -91,7 +89,7 @@ void do_page_fault(unsigned long address, struct pt_regs *regs)
> return;
> }
>
> - info.si_code = SEGV_MAPERR;
> + si_code = SEGV_MAPERR;
>
> /*
> * If we're in an interrupt or have no user
> @@ -119,7 +117,7 @@ void do_page_fault(unsigned long address, struct pt_regs *regs)
> * we can handle it..
> */
> good_area:
> - info.si_code = SEGV_ACCERR;
> + si_code = SEGV_ACCERR;
>
> /* Handle protection violation, execute on heap or stack */
>
> @@ -204,11 +202,7 @@ void do_page_fault(unsigned long address, struct pt_regs *regs)
> /* User mode accesses just cause a SIGSEGV */
> if (user_mode(regs)) {
> tsk->thread.fault_address = address;
> - info.si_signo = SIGSEGV;
> - info.si_errno = 0;
> - /* info.si_code has been set above */
> - info.si_addr = (void __user *)address;
> - force_sig_info(SIGSEGV, &info, tsk);
> + force_sig_fault(SIGSEGV, si_code, (void __user *)address, tsk);
> return;
> }
>
> @@ -243,9 +237,5 @@ void do_page_fault(unsigned long address, struct pt_regs *regs)
> goto no_context;
>
> tsk->thread.fault_address = address;
> - info.si_signo = SIGBUS;
> - info.si_errno = 0;
> - info.si_code = BUS_ADRERR;
> - info.si_addr = (void __user *)address;
> - force_sig_info(SIGBUS, &info, tsk);
> + force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *)address, tsk);
> }