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Date:   Sun, 26 Mar 2023 13:42:35 -0500 (EST)
From:   =?UTF-8?Q?Thomas_Wei=C3=9Fschuh_?= <thomas@t-8ch.de>
To:     Alexey Dobriyan <adobriyan@gmail.com>
Cc:     Willy Tarreau <w@1wt.eu>,
        =?UTF-8?Q?Thomas_Wei=C3=9Fschuh?= <linux@weissschuh.net>,
        "Paul E. McKenney" <paulmck@kernel.org>,
        linux-kernel@vger.kernel.org
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References: <89a960c7-0c9b-43ab-9fc8-a68405f7ed6a@p183>
Subject: Re: [PATCH 6/8] tools/nolibc: tests: add test for -fstack-protector
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Mar 26, 2023 13:30:21 Alexey Dobriyan <adobriyan@gmail.com>:

> Willy Tarreau wrote:
>> #if defined(__clang__)
>> __attribute__((optnone))
>> #elif defined(__GNUC__)
>> __attribute__((optimize("O0")))
>> #endif
>> static int smash_stack(void)
>> {
>> =C2=A0=C2=A0=C2=A0 char buf[100];
>>
>> =C2=A0=C2=A0=C2=A0 for (size_t i =3D 0; i < 200; i++)
>> =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0 buf[i] =3D 'P';
>>
>> =C2=A0=C2=A0=C2=A0 return 1;
>> }
>
> If you want to corrupt the stack, corrupt the stack!

I do!

> asm(
> ".globl f\n"
> "f:\n"
> "movq $0, (%rsp)\n"
> "ret\n"
> ".type f,@function\n"
> ".size f,.-f"
> );
> > No problems with optimisation levels.

Wouldn't this be architecture-specific?