From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org
X-Spam-Level: 
X-Spam-Status: No, score=0.2 required=5.0 tests=DKIM_ADSP_CUSTOM_MED,
	DKIM_INVALID,DKIM_SIGNED,FREEMAIL_FROM,T_SCC_BODY_TEXT_LINE
	autolearn=no autolearn_force=no version=3.4.4
Received: (qmail 22846 invoked from network); 8 May 2022 17:40:22 -0000
Received: from 9front.inri.net (168.235.81.73)
  by inbox.vuxu.org with ESMTPUTF8; 8 May 2022 17:40:22 -0000
Received: from mail-lj1-f181.google.com ([209.85.208.181]) by 9front; Sun May  8 13:38:34 -0400 2022
Received: by mail-lj1-f181.google.com with SMTP id v4so14616852ljd.10
        for <9front@9front.org>; Sun, 08 May 2022 10:38:28 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
        d=gmail.com; s=20210112;
        h=mime-version:from:date:message-id:subject:to;
        bh=uv1g8BLHRpHu1i0DQdsKWFeB1gjPOI77nagUySlq0Fo=;
        b=D8axgXJ51UI4RJ/XtUThBa43UF9xle0nyQUMg+ZC6Mh830Tpp7q/JXxGQaVSoodHiu
         DoTg+YsUnhGvkiZPPTEtd5eFrGZdGGl0MJE147TZTXOR1YMdlVRyesE+cOsQbL+lCpCe
         ZczXb9bJaC2Fb2pqFfq9zmZtU3wmfX6UhlJ6Cg1CgEfZmNfZKKHDLQiZdWVhdfQC5Jg/
         UH90wbvJAqxbbLp0m0jvU1L6qUHv0STCYuzqDZ5oq0W7lM5g6fDr+Y4NR8SDRZ1gSYzr
         HjYApRDQ5YQ1EWFVhBE1pilGZxPofGDPD0TamO6Kn5CAANv4Y3ldk1Dsvj6br8EEHTpT
         qAug==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
        d=1e100.net; s=20210112;
        h=x-gm-message-state:mime-version:from:date:message-id:subject:to;
        bh=uv1g8BLHRpHu1i0DQdsKWFeB1gjPOI77nagUySlq0Fo=;
        b=m7tH5/dWhwp2XxWliW9aBpmmXkqsuiITCRHYRa71+HrcCaREK0ANw+DXu9AUHehsi4
         9rEaHvzNLN0ZSCHNBo6TRIHK780zqpFdNgUAfHFa+hFg9k0euG/bmBFLcujdifeSoa6d
         9sYStCJuZx9AVi3f1YAtRA7JUZq20N1/ERzFcuWBlrWXlIaQfTb+xGXB53je5NoAuk1L
         pKxM2JP1MSI3aKHmBXd1XHduIizZXapPLLaknn0mX2aq5busRx5ZHmLX35g0RaV8K4/n
         2irFSaOeCNXcMhZCNXOnPlv2ZpzyEYfKozYxzosIGhxtZ2LOrqPXpzWDKXu18sm2ZgW7
         vJgQ==
X-Gm-Message-State: AOAM532KBiKar4GeDZhPAg1u2mVtBH9Mm8HYlgQUS0PNlQY1scrwEe5U
	EyAV/vizizDR3UsP6Ntsr5coaVUY0GQnXQQZ5DG4mUr7Pag=
X-Google-Smtp-Source: ABdhPJwDgIm9TEoD0wm8prPMRH4mLKLuc1q84rddANUDE5IR5aLphaVOVr4QyeX7mNfbrFrYxZ5K/s4GlC5bAqqi2Vo=
X-Received: by 2002:a2e:9d08:0:b0:249:b8b6:8f7a with SMTP id
 t8-20020a2e9d08000000b00249b8b68f7amr8157238lji.310.1652031507745; Sun, 08
 May 2022 10:38:27 -0700 (PDT)
MIME-Version: 1.0
Received: by 2002:a05:6512:3d87:0:0:0:0 with HTTP; Sun, 8 May 2022 10:38:27
 -0700 (PDT)
From: istvan bak <bdhpfl@gmail.com>
Date: Sun, 8 May 2022 17:38:27 +0000
Message-ID: <CAO+DOcqq4RSa_vyhEHBxjGgmJ-ux_B3ShWMN-cy5YquWnaChtw@mail.gmail.com>
To: 9front <9front@9front.org>
Content-Type: text/plain; charset="UTF-8"
List-ID: <9front.9front.org>
List-Help: <http://lists.9front.org>
X-Glyph: ➈
X-Bullshit: stable flexible property WEB2.0 over SQL hypervisor general-purpose manager 
Subject: [9front] exec suicide: sys: bad address in syscall
Reply-To: 9front@9front.org
Precedence: bulk

Hello. The below program suicides on a call to fork/exec. If I made
the mistake, then I can't see it. If I didn't, then I don't know how
to debug the kernel(?), and I don't have time to stare at it for days
on end :/.

If I remove the Waitmsg, it doesn't repro. If I remove the print(""),
it doesn't repro. if i inline the body, it doesn't repro. something
something callstack mumble address syscall mumble. It repros on amd64,
but not 386.

http://sysinfo.9front.org/src/460/body

term% mk 6.red
6c -FTVw red.c
6l  -o 6.red red.6
term% 6.red
term% 6.red 666: suicide: invalid address 0x7fff00000000/1 in sys call
pc=0x200216
6.red 666: suicide: sys: bad address in syscall pc=0x200216
6.red 667: suicide: invalid address 0x7fff00000000/1 in sys call pc=0x200216
6.red 667: suicide: sys: bad address in syscall pc=0x200216

term% acid 666
/proc/666/text:amd64 plan 9 executable
/sys/lib/acid/port
/sys/lib/acid/amd64
acid: lstk()
exec(a0=0x4009a0)+0xe /sys/src/libc/9syscall/exec.s:6
execl(f=0x4009a8)+0x13 /sys/src/libc/port/execl.c:8
rc(cmd=0x4009c1)+0x4f /usr/glenda/riv/nag/red.c:17
run()+0x19 /usr/glenda/riv/nag/red.c:29
	i=0x20014500000001
main()+0x9 /usr/glenda/riv/nag/red.c:69
_main+0x40 /sys/src/libc/amd64/main9.s:15
acid:
echo kill > /proc/666/ctl
term% cat red.c
#include <u.h>
#include <libc.h>

int
rc(char *cmd)
{
	int r;
	Waitmsg *w;

	SET(w); USED(w);
	r = fork();
	switch(r){
	case -1:
		return -1;
	case 0:
		execl("/bin/rc", "/bin/rc", "-c", cmd, 0);
		sysfatal("exec returned");
	}
	return 0;
}

void
run(void)
{
	int i;

	for(i = 0; i < 3; i++){
		rc("test");
		print("");
	}
}

void
run2(void)
{
	int i;
	int r;
	Waitmsg *w;

	SET(w); USED(w);
	for(i = 0; i < 3; i++){
		r = fork();
		switch(r){
		case -1:
			continue;
		case 0:
			execl("/bin/rc", "/bin/rc", "-c", "test", 0);
			sysfatal("exec returned");
		}
		print("");
	}
}

void
main()
{
	//to test: uncomment one of the below lines
	//reproduces on amd64, but not on 386


	// this reproduces
	run();


	// this doesnt
	//run2();


	exits(0);
}