2018-04-20 9:03 GMT+08:00 Eric W. Biederman <ebiederm@xxxxxxxxxxxx>:
> As originally committed do_revisn would deliver a siginfo for SIGILL
> with an si_code composed of random stack contents. That makes no
> sense and is not something userspace can depend on. So simplify
> the code and just use "force_sig(SIG_ILL, current)" instead.
>
> Fixes: 2923f5ea7738 ("nds32: Exception handling")
> Cc: Vincent Chen <vincentc@xxxxxxxxxxxxx>
> Cc: Greentime Hu <greentime@xxxxxxxxxxxxx>
> Cc: Arnd Bergmann <arnd@xxxxxxxx>
> Signed-off-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx>
> ---
> arch/nds32/kernel/traps.c | 5 +----
> 1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/arch/nds32/kernel/traps.c b/arch/nds32/kernel/traps.c
> index 65961bf91d64..8e9a5b1f6234 100644
> --- a/arch/nds32/kernel/traps.c
> +++ b/arch/nds32/kernel/traps.c
> @@ -356,14 +356,11 @@ void do_dispatch_tlb_misc(unsigned long entry, unsigned long addr,
>
> void do_revinsn(struct pt_regs *regs)
> {
> - siginfo_t si;
> pr_emerg("Reserved Instruction\n");
> show_regs(regs);
> if (!user_mode(regs))
> do_exit(SIGILL);
> - si.si_signo = SIGILL;
> - si.si_errno = 0;
> - force_sig_info(SIGILL, &si, current);
> + force_sig(SIGILL, current);
> }
>
> #ifdef CONFIG_ALIGNMENT_TRAP
> --
> 2.14.1
>
You are right we do not store any valuable information in sigingo_t now.
However, We hope more information can be recorded by force_sig_fault()
as below instead of calling force_sig() directly.
- force_sig(SIGILL, current);
+ force_sig_fault(SIGILL, ILL_ILLTRP,
+ (void __user *)instruction_pointer(regs), current);
Thanks
Vincent Chen
