ericonr
/
util-linux
mirror of https://github.com/ericonr/util-linux.git
1
0
Fork 0
Code Issues Projects Releases Wiki Activity

agetty: close tty before vhangup() 

Let's close all tty file descriptors if called with --hangup option.

References: https://lkml.org/lkml/2012/6/5/145
Signed-off-by: Karel Zak <kzak@redhat.com>
This commit is contained in:
Karel Zak 2012-07-12 16:31:22 +02:00
parent 4459448fbd
commit 783b08fc1c
1 changed files with 30 additions and 20 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

50
term-utils/agetty.c
View File

@ -264,7 +264,7 @@ static void login_options_to_argv(char *argv[], int *argc, char *str, char *user
static char *fakehost;
#ifdef DEBUGGING
#define debug(s) do { fprintf(dbf,s); fflush(dbf); while (0)
#define debug(s) do { fprintf(dbf,s); fflush(dbf); } while (0)
FILE *dbf;
#else
#define debug(s) do { ; } while (0)
@ -869,10 +869,12 @@ static void update_utmp(struct options *op)
static void open_tty(char *tty, struct termios *tp, struct options *op)
{
const pid_t pid = getpid();
int serial;
int serial, closed = 0;
/* Set up new standard input, unless we are given an already opened port. */
sleep(10);
if (strcmp(tty, "-") != 0) {
char buf[PATH_MAX+1];
struct group *gr = NULL;
@ -919,27 +921,33 @@ static void open_tty(char *tty, struct termios *tp, struct options *op)
log_warn("/dev/%s: cannot get controlling tty: %m", tty);
}
if (op->flags & F_HANGUP) {
/*
* vhangup() will replace all open file descriptors in the kernel
* that point to our controlling tty by a dummy that will deny
* further reading/writing to our device. It will also reset the
* tty to sane defaults, so we don't have to modify the tty device
* for sane settings. We also get a SIGHUP/SIGCONT.
*/
if (vhangup())
log_err("/dev/%s: vhangup() failed: %m", tty);
if (ioctl(fd, TIOCNOTTY))
debug("TIOCNOTTY ioctl failed\n");
}
close(fd);
close(STDIN_FILENO);
errno = 0;
if (op->flags & F_HANGUP) {
if (ioctl(fd, TIOCNOTTY))
debug("TIOCNOTTY ioctl failed\n");
/*
* Let's close all file decriptors before vhangup
* https://lkml.org/lkml/2012/6/5/145
*/
close(fd);
close(STDOUT_FILENO);
close(STDERR_FILENO);
errno = 0;
closed = 1;
if (vhangup())
log_err("/dev/%s: vhangup() failed: %m", tty);
} else
close(fd);
debug("open(2)\n");
if (open(buf, O_RDWR|O_NOCTTY|O_NONBLOCK, 0) != 0)
log_err(_("/dev/%s: cannot open as standard input: %m"), tty);
if (((tid = tcgetsid(STDIN_FILENO)) < 0) || (pid != tid)) {
if (ioctl(STDIN_FILENO, TIOCSCTTY, 1) == -1)
log_warn("/dev/%s: cannot get controlling tty: %m", tty);
@ -961,9 +969,11 @@ static void open_tty(char *tty, struct termios *tp, struct options *op)
log_warn("/dev/%s: cannot set process group: %m", tty);
/* Get rid of the present outputs. */
close(STDOUT_FILENO);
close(STDERR_FILENO);
errno = 0;
if (!closed) {
close(STDOUT_FILENO);
close(STDERR_FILENO);
errno = 0;
}
/* Set up standard output and standard error file descriptors. */
debug("duping\n");