On Fri, Apr 20, 2018 at 09:38:05AM -0500, Eric W. Biederman wrote:
> Filling in struct siginfo before calling force_sig_info a tedious and
> error prone process, where once in a great while the wrong fields
> are filled out, and siginfo has been inconsistently cleared.
>
> Simplify this process by using the helper force_sig_fault. Which
> takes as a parameters all of the information it needs, ensures
> all of the fiddly bits of filling in struct siginfo are done properly
> and then calls force_sig_info.
>
> In short about a 5 line reduction in code for every time force_sig_info
> is called, which makes the calling function clearer.
>
> Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
> Cc: Rich Felker <dalias@xxxxxxxx>
> Cc: linux-sh@xxxxxxxxxxxxxxx
> Signed-off-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
> ---
> arch/sh/kernel/traps_32.c | 19 +++++--------------
> arch/sh/math-emu/math.c | 9 ++-------
> arch/sh/mm/fault.c | 10 +---------
> 3 files changed, 8 insertions(+), 30 deletions(-)
>
> diff --git a/arch/sh/kernel/traps_32.c b/arch/sh/kernel/traps_32.c
> index e85e59c3d6df..660a4bc17698 100644
> --- a/arch/sh/kernel/traps_32.c
> +++ b/arch/sh/kernel/traps_32.c
> @@ -477,7 +477,6 @@ asmlinkage void do_address_error(struct pt_regs *regs,
> {
> unsigned long error_code = 0;
> mm_segment_t oldfs;
> - siginfo_t info;
> insn_size_t instruction;
> int tmp;
>
> @@ -537,12 +536,7 @@ asmlinkage void do_address_error(struct pt_regs *regs,
> "access (PC %lx PR %lx)\n", current->comm, regs->pc,
> regs->pr);
>
> - clear_siginfo(&info);
> - info.si_signo = SIGBUS;
> - info.si_errno = 0;
> - info.si_code = si_code;
> - info.si_addr = (void __user *)address;
> - force_sig_info(SIGBUS, &info, current);
> + force_sig_fault(SIGBUS, si_code, (void __user *)address, current);
> } else {
> inc_unaligned_kernel_access();
>
> @@ -599,20 +593,17 @@ int is_dsp_inst(struct pt_regs *regs)
> #ifdef CONFIG_CPU_SH2A
> asmlinkage void do_divide_error(unsigned long r4)
> {
> - siginfo_t info;
> + int code;
>
> - clear_siginfo(&info);
> switch (r4) {
> case TRAP_DIVZERO_ERROR:
> - info.si_code = FPE_INTDIV;
> + code = FPE_INTDIV;
> break;
> case TRAP_DIVOVF_ERROR:
> - info.si_code = FPE_INTOVF;
> + code = FPE_INTOVF;
> break;
> }
> -
> - info.si_signo = SIGFPE;
> - force_sig_info(info.si_signo, &info, current);
> + force_sig_fault(SIGFPE, code, NULL, current);
> }
> #endif
>
> diff --git a/arch/sh/math-emu/math.c b/arch/sh/math-emu/math.c
> index d6d2213df078..a0fa8fc88739 100644
> --- a/arch/sh/math-emu/math.c
> +++ b/arch/sh/math-emu/math.c
> @@ -507,7 +507,6 @@ static int ieee_fpe_handler(struct pt_regs *regs)
> unsigned short insn = *(unsigned short *)regs->pc;
> unsigned short finsn;
> unsigned long nextpc;
> - siginfo_t info;
> int nib[4] = {
> (insn >> 12) & 0xf,
> (insn >> 8) & 0xf,
> @@ -560,12 +559,8 @@ static int ieee_fpe_handler(struct pt_regs *regs)
> ~(FPSCR_CAUSE_MASK | FPSCR_FLAG_MASK);
> task_thread_info(tsk)->status |= TS_USEDFPU;
> } else {
> - clear_siginfo(&info);
> - info.si_signo = SIGFPE;
> - info.si_errno = 0;
> - info.si_code = FPE_FLTINV;
> - info.si_addr = (void __user *)regs->pc;
> - force_sig_info(SIGFPE, &info, tsk);
> + force_sig_fault(SIGFPE, FPE_FLTINV,
> + (void __user *)regs->pc, tsk);
> }
>
> regs->pc = nextpc;
> diff --git a/arch/sh/mm/fault.c b/arch/sh/mm/fault.c
> index 4c98b6f20e02..b8e7bb84b6b1 100644
> --- a/arch/sh/mm/fault.c
> +++ b/arch/sh/mm/fault.c
> @@ -42,15 +42,7 @@ static void
> force_sig_info_fault(int si_signo, int si_code, unsigned long address,
> struct task_struct *tsk)
> {
> - siginfo_t info;
> -
> - clear_siginfo(&info);
> - info.si_signo = si_signo;
> - info.si_errno = 0;
> - info.si_code = si_code;
> - info.si_addr = (void __user *)address;
> -
> - force_sig_info(si_signo, &info, tsk);
> + force_sig_fault(si_signo, si_code, (void __user *)address, tsk);
> }
>
> /*
> --
> 2.14.1
Acked-by: Rich Felker <dalias@xxxxxxxx>
