Re: [PATCH] signal/x86: Don't send SIGSEGV twice on SEGV_PKUERR

[Borislav Petkov]

On Tue, Jun 01, 2021 at 04:52:03PM +0800, Jiashuo Liang wrote:
> Before this patch, the __bad_area_nosemaphore function calls both
> force_sig_pkuerr and force_sig_fault when handling SEGV_PKUERR. This does
> not cause problems because the second signal is filtered by the
> legacy_queue check in __send_signal.

I'm likely missing something but the first signal gets filtered by that
same legacy_queue() check too, no?

Because both calls end up in

	force_sig_info_to_task(info, current);

with the info struct populated with:

	info.si_signo = SIGSEGV;
        info.si_errno = 0;
        info.si_code  = SEGV_PKUERR;
        info.si_addr  = addr;
        info.si_pkey  = pkey;

except the second call - force_sig_fault() - doesn't put pkey in
->si_pkey.

So what's up?

Thx.

-- 
Regards/Gruss,
    Boris.

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