 37185b3324
			
		
	
	
	37185b3324
	
	
	
		
			
			Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Richard Weinberger <richard@nod.at>
		
			
				
	
	
		
			144 lines
		
	
	
	
		
			3.2 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			144 lines
		
	
	
	
		
			3.2 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
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|  * Licensed under the GPL
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|  */
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| 
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| #include <stdio.h>
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| #include <stdlib.h>
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| #include <unistd.h>
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| #include <errno.h>
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| #include <signal.h>
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| #include <string.h>
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| #include <termios.h>
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| #include <wait.h>
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| #include <sys/mman.h>
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| #include <sys/utsname.h>
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| #include <os.h>
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| 
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| void stack_protections(unsigned long address)
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| {
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| 	if (mprotect((void *) address, UM_THREAD_SIZE,
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| 		    PROT_READ | PROT_WRITE | PROT_EXEC) < 0)
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| 		panic("protecting stack failed, errno = %d", errno);
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| }
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| 
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| int raw(int fd)
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| {
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| 	struct termios tt;
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| 	int err;
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| 
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| 	CATCH_EINTR(err = tcgetattr(fd, &tt));
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| 	if (err < 0)
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| 		return -errno;
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| 
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| 	cfmakeraw(&tt);
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| 
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| 	CATCH_EINTR(err = tcsetattr(fd, TCSADRAIN, &tt));
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| 	if (err < 0)
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| 		return -errno;
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| 
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| 	/*
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| 	 * XXX tcsetattr could have applied only some changes
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| 	 * (and cfmakeraw() is a set of changes)
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| 	 */
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| 	return 0;
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| }
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| 
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| void setup_machinename(char *machine_out)
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| {
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| 	struct utsname host;
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| 
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| 	uname(&host);
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| #ifdef UML_CONFIG_UML_X86
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| # ifndef UML_CONFIG_64BIT
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| 	if (!strcmp(host.machine, "x86_64")) {
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| 		strcpy(machine_out, "i686");
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| 		return;
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| 	}
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| # else
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| 	if (!strcmp(host.machine, "i686")) {
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| 		strcpy(machine_out, "x86_64");
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| 		return;
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| 	}
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| # endif
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| #endif
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| 	strcpy(machine_out, host.machine);
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| }
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| 
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| void setup_hostinfo(char *buf, int len)
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| {
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| 	struct utsname host;
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| 
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| 	uname(&host);
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| 	snprintf(buf, len, "%s %s %s %s %s", host.sysname, host.nodename,
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| 		 host.release, host.version, host.machine);
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| }
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| 
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| /*
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|  * We cannot use glibc's abort(). It makes use of tgkill() which
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|  * has no effect within UML's kernel threads.
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|  * After that glibc would execute an invalid instruction to kill
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|  * the calling process and UML crashes with SIGSEGV.
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|  */
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| static inline void __attribute__ ((noreturn)) uml_abort(void)
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| {
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| 	sigset_t sig;
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| 
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| 	fflush(NULL);
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| 
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| 	if (!sigemptyset(&sig) && !sigaddset(&sig, SIGABRT))
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| 		sigprocmask(SIG_UNBLOCK, &sig, 0);
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| 
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| 	for (;;)
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| 		if (kill(getpid(), SIGABRT) < 0)
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| 			exit(127);
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| }
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| 
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| void os_dump_core(void)
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| {
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| 	int pid;
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| 
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| 	signal(SIGSEGV, SIG_DFL);
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| 
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| 	/*
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| 	 * We are about to SIGTERM this entire process group to ensure that
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| 	 * nothing is around to run after the kernel exits.  The
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| 	 * kernel wants to abort, not die through SIGTERM, so we
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| 	 * ignore it here.
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| 	 */
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| 
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| 	signal(SIGTERM, SIG_IGN);
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| 	kill(0, SIGTERM);
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| 	/*
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| 	 * Most of the other processes associated with this UML are
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| 	 * likely sTopped, so give them a SIGCONT so they see the
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| 	 * SIGTERM.
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| 	 */
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| 	kill(0, SIGCONT);
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| 
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| 	/*
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| 	 * Now, having sent signals to everyone but us, make sure they
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| 	 * die by ptrace.  Processes can survive what's been done to
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| 	 * them so far - the mechanism I understand is receiving a
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| 	 * SIGSEGV and segfaulting immediately upon return.  There is
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| 	 * always a SIGSEGV pending, and (I'm guessing) signals are
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| 	 * processed in numeric order so the SIGTERM (signal 15 vs
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| 	 * SIGSEGV being signal 11) is never handled.
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| 	 *
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| 	 * Run a waitpid loop until we get some kind of error.
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| 	 * Hopefully, it's ECHILD, but there's not a lot we can do if
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| 	 * it's something else.  Tell os_kill_ptraced_process not to
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| 	 * wait for the child to report its death because there's
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| 	 * nothing reasonable to do if that fails.
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| 	 */
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| 
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| 	while ((pid = waitpid(-1, NULL, WNOHANG | __WALL)) > 0)
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| 		os_kill_ptraced_process(pid, 0);
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| 
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| 	uml_abort();
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| }
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| 
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| void um_early_printk(const char *s, unsigned int n)
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| {
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| 	printf("%.*s", n, s);
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| }
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