Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/*
2 * Copyright (C) 2000, 2001, 2002 Jeff Dike (jdike@karaya.com)
3 * Licensed under the GPL
4 */
5
6#include <stdio.h>
7#include <stdlib.h>
8#include <unistd.h>
9#include <limits.h>
10#include <sys/mman.h>
11#include <sys/stat.h>
12#include <sys/utsname.h>
13#include <sys/param.h>
14#include <sys/time.h>
15#include "asm/types.h"
16#include <ctype.h>
17#include <signal.h>
18#include <wait.h>
19#include <errno.h>
20#include <stdarg.h>
21#include <sched.h>
22#include <termios.h>
23#include <string.h>
24#include "kern_util.h"
25#include "user.h"
26#include "mem_user.h"
27#include "init.h"
28#include "ptrace_user.h"
29#include "uml-config.h"
30#include "os.h"
31#include "longjmp.h"
32#include "kern_constants.h"
33
34void stack_protections(unsigned long address)
35{
36 if(mprotect((void *) address, UM_THREAD_SIZE,
37 PROT_READ | PROT_WRITE | PROT_EXEC) < 0)
38 panic("protecting stack failed, errno = %d", errno);
39}
40
41int raw(int fd)
42{
43 struct termios tt;
44 int err;
45
46 CATCH_EINTR(err = tcgetattr(fd, &tt));
47 if(err < 0)
48 return -errno;
49
50 cfmakeraw(&tt);
51
52 CATCH_EINTR(err = tcsetattr(fd, TCSADRAIN, &tt));
53 if(err < 0)
54 return -errno;
55
56 /* XXX tcsetattr could have applied only some changes
57 * (and cfmakeraw() is a set of changes) */
58 return 0;
59}
60
61void setup_machinename(char *machine_out)
62{
63 struct utsname host;
64
65 uname(&host);
66#ifdef UML_CONFIG_UML_X86
67# ifndef UML_CONFIG_64BIT
68 if (!strcmp(host.machine, "x86_64")) {
69 strcpy(machine_out, "i686");
70 return;
71 }
72# else
73 if (!strcmp(host.machine, "i686")) {
74 strcpy(machine_out, "x86_64");
75 return;
76 }
77# endif
78#endif
79 strcpy(machine_out, host.machine);
80}
81
82void setup_hostinfo(char *buf, int len)
83{
84 struct utsname host;
85
86 uname(&host);
87 snprintf(buf, len, "%s %s %s %s %s", host.sysname, host.nodename,
88 host.release, host.version, host.machine);
89}
90
91int setjmp_wrapper(void (*proc)(void *, void *), ...)
92{
93 va_list args;
94 jmp_buf buf;
95 int n;
96
97 n = UML_SETJMP(&buf);
98 if(n == 0){
99 va_start(args, proc);
100 (*proc)(&buf, &args);
101 }
102 va_end(args);
103 return n;
104}
105
106void os_dump_core(void)
107{
108 int pid;
109
110 signal(SIGSEGV, SIG_DFL);
111
112 /*
113 * We are about to SIGTERM this entire process group to ensure that
114 * nothing is around to run after the kernel exits. The
115 * kernel wants to abort, not die through SIGTERM, so we
116 * ignore it here.
117 */
118
119 signal(SIGTERM, SIG_IGN);
120 kill(0, SIGTERM);
121 /*
122 * Most of the other processes associated with this UML are
123 * likely sTopped, so give them a SIGCONT so they see the
124 * SIGTERM.
125 */
126 kill(0, SIGCONT);
127
128 /*
129 * Now, having sent signals to everyone but us, make sure they
130 * die by ptrace. Processes can survive what's been done to
131 * them so far - the mechanism I understand is receiving a
132 * SIGSEGV and segfaulting immediately upon return. There is
133 * always a SIGSEGV pending, and (I'm guessing) signals are
134 * processed in numeric order so the SIGTERM (signal 15 vs
135 * SIGSEGV being signal 11) is never handled.
136 *
137 * Run a waitpid loop until we get some kind of error.
138 * Hopefully, it's ECHILD, but there's not a lot we can do if
139 * it's something else. Tell os_kill_ptraced_process not to
140 * wait for the child to report its death because there's
141 * nothing reasonable to do if that fails.
142 */
143
144 while ((pid = waitpid(-1, NULL, WNOHANG | __WALL)) > 0)
145 os_kill_ptraced_process(pid, 0);
146
147 abort();
148}