busybox/procps/kill.c
Pere Orga 9283d7c5c2 kill: fix infinite loop when passed PIDs are not valid numbers
Signed-off-by: Pere Orga <gotrunks@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2011-03-07 17:00:25 +01:00

244 lines
5.6 KiB
C

/* vi: set sw=4 ts=4: */
/*
* Mini kill/killall[5] implementation for busybox
*
* Copyright (C) 1995, 1996 by Bruce Perens <bruce@pixar.com>.
* Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
#include "libbb.h"
/* Note: kill_main is directly called from shell in order to implement
* kill built-in. Shell substitutes job ids with process groups first.
*
* This brings some complications:
*
* + we can't use xfunc here
* + we can't use applet_name
* + we can't use bb_show_usage
* (Above doesn't apply for killall[5] cases)
*
* kill %n gets translated into kill ' -<process group>' by shell (note space!)
* This is needed to avoid collision with kill -9 ... syntax
*/
int kill_main(int argc, char **argv)
{
char *arg;
pid_t pid;
int signo = SIGTERM, errors = 0, quiet = 0;
#if !ENABLE_KILLALL && !ENABLE_KILLALL5
#define killall 0
#define killall5 0
#else
/* How to determine who we are? find 3rd char from the end:
* kill, killall, killall5
* ^i ^a ^l - it's unique
* (checking from the start is complicated by /bin/kill... case) */
const char char3 = argv[0][strlen(argv[0]) - 3];
#define killall (ENABLE_KILLALL && char3 == 'a')
#define killall5 (ENABLE_KILLALL5 && char3 == 'l')
#endif
/* Parse any options */
argc--;
arg = *++argv;
if (argc < 1 || arg[0] != '-') {
goto do_it_now;
}
/* The -l option, which prints out signal names.
* Intended usage in shell:
* echo "Died of SIG`kill -l $?`"
* We try to mimic what kill from coreutils-6.8 does */
if (arg[1] == 'l' && arg[2] == '\0') {
if (argc == 1) {
/* Print the whole signal list */
print_signames();
return 0;
}
/* -l <sig list> */
while ((arg = *++argv)) {
if (isdigit(arg[0])) {
signo = bb_strtou(arg, NULL, 10);
if (errno) {
bb_error_msg("unknown signal '%s'", arg);
return EXIT_FAILURE;
}
/* Exitcodes >= 0x80 are to be treated
* as "killed by signal (exitcode & 0x7f)" */
puts(get_signame(signo & 0x7f));
/* TODO: 'bad' signal# - coreutils says:
* kill: 127: invalid signal
* we just print "127" instead */
} else {
signo = get_signum(arg);
if (signo < 0) {
bb_error_msg("unknown signal '%s'", arg);
return EXIT_FAILURE;
}
printf("%d\n", signo);
}
}
/* If they specified -l, we are all done */
return EXIT_SUCCESS;
}
/* The -q quiet option */
if (killall && arg[1] == 'q' && arg[2] == '\0') {
quiet = 1;
arg = *++argv;
argc--;
if (argc < 1)
bb_show_usage();
if (arg[0] != '-')
goto do_it_now;
}
arg++; /* skip '-' */
/* -o PID? (if present, it always is at the end of command line) */
if (killall5 && arg[0] == 'o')
goto do_it_now;
if (argc > 1 && arg[0] == 's' && arg[1] == '\0') { /* -s SIG? */
argc--;
arg = *++argv;
} /* else it must be -SIG */
signo = get_signum(arg);
if (signo < 0) { /* || signo > MAX_SIGNUM ? */
bb_error_msg("bad signal name '%s'", arg);
return EXIT_FAILURE;
}
arg = *++argv;
argc--;
do_it_now:
pid = getpid();
if (killall5) {
pid_t sid;
procps_status_t* p = NULL;
int ret = 0;
/* Find out our session id */
sid = getsid(pid);
/* Stop all processes */
kill(-1, SIGSTOP);
/* Signal all processes except those in our session */
while ((p = procps_scan(p, PSSCAN_PID|PSSCAN_SID))) {
int i;
if (p->sid == (unsigned)sid
|| p->pid == (unsigned)pid
|| p->pid == 1)
continue;
/* All remaining args must be -o PID options.
* Check p->pid against them. */
for (i = 0; i < argc; i++) {
pid_t omit;
arg = argv[i];
if (arg[0] != '-' || arg[1] != 'o') {
bb_error_msg("bad option '%s'", arg);
ret = 1;
goto resume;
}
arg += 2;
if (!arg[0] && argv[++i])
arg = argv[i];
omit = bb_strtoi(arg, NULL, 10);
if (errno) {
bb_error_msg("invalid number '%s'", arg);
ret = 1;
goto resume;
}
if (p->pid == omit)
goto dont_kill;
}
kill(p->pid, signo);
dont_kill: ;
}
resume:
/* And let them continue */
kill(-1, SIGCONT);
return ret;
}
/* Pid or name is required for kill/killall */
if (argc < 1) {
bb_error_msg("you need to specify whom to kill");
return EXIT_FAILURE;
}
if (killall) {
/* Looks like they want to do a killall. Do that */
while (arg) {
pid_t* pidList;
pidList = find_pid_by_name(arg);
if (*pidList == 0) {
errors++;
if (!quiet)
bb_error_msg("%s: no process killed", arg);
} else {
pid_t *pl;
for (pl = pidList; *pl; pl++) {
if (*pl == pid)
continue;
if (kill(*pl, signo) == 0)
continue;
errors++;
if (!quiet)
bb_perror_msg("can't kill pid %d", (int)*pl);
}
}
free(pidList);
arg = *++argv;
}
return errors;
}
/* Looks like they want to do a kill. Do that */
while (arg) {
#if ENABLE_ASH || ENABLE_HUSH
/*
* We need to support shell's "hack formats" of
* " -PRGP_ID" (yes, with a leading space)
* and " PID1 PID2 PID3" (with degenerate case "")
*/
while (*arg != '\0') {
char *end;
if (*arg == ' ')
arg++;
pid = bb_strtoi(arg, &end, 10);
if (errno && (errno != EINVAL || *end != ' ')) {
bb_error_msg("invalid number '%s'", arg);
*end = '\0';
errors++;
} else if (kill(pid, signo) != 0) {
bb_perror_msg("can't kill pid %d", (int)pid);
errors++;
}
arg = end; /* can only point to ' ' or '\0' now */
}
#else
pid = bb_strtoi(arg, NULL, 10);
if (errno) {
bb_error_msg("invalid number '%s'", arg);
errors++;
} else if (kill(pid, signo) != 0) {
bb_perror_msg("can't kill pid %d", (int)pid);
errors++;
}
#endif
arg = *++argv;
}
return errors;
}