isa/sudo
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Move code to suspend sudo when no pty is in use to separate file.

Browse Source 
Use this in test_ptrace.c to be able to suspend just like sudo does.
This commit is contained in:
Todd C. Miller
2022-05-18 07:29:55 -06:00
parent a52e3776f0
commit 0ea431e392
7 changed files with 190 additions and 118 deletions
Download Patch File Download Diff File Expand all files Collapse all files

80
src/exec_nopty.c
View File

@@ -558,9 +558,7 @@ handle_sigchld_nopty(struct exec_closure_nopty *ec)
}
if (WIFSTOPPED(status)) {
struct sigaction sa, osa;
pid_t saved_pgrp = -1;
int fd, signo = WSTOPSIG(status);
const int signo = WSTOPSIG(status);
if (sig2str(signo, signame) == -1)
(void)snprintf(signame, sizeof(signame), "%d", signo);
@@ -573,79 +571,9 @@ handle_sigchld_nopty(struct exec_closure_nopty *ec)
continue;
}
/* Special handling for job control in the main command only. */
if (pid != ec->cmnd_pid)
continue;
/*
* Save the controlling terminal's process group so we can restore
* it after we resume, if needed. Most well-behaved shells change
* the pgrp back to its original value before suspending so we must
* not try to restore in that case, lest we race with the command
* upon resume, potentially stopping sudo with SIGTTOU while the
* command continues to run.
*/
fd = open(_PATH_TTY, O_RDWR);
if (fd != -1) {
saved_pgrp = tcgetpgrp(fd);
if (saved_pgrp == -1) {
close(fd);
fd = -1;
}
}
if (saved_pgrp != -1) {
/*
* Command was stopped trying to access the controlling
* terminal. If the command has a different pgrp and we
* own the controlling terminal, give it to the command's
* pgrp and let it continue.
*/
if (signo == SIGTTOU || signo == SIGTTIN) {
if (saved_pgrp == ec->ppgrp) {
pid_t cmnd_pgrp = getpgid(ec->cmnd_pid);
if (cmnd_pgrp != ec->ppgrp) {
if (tcsetpgrp_nobg(fd, cmnd_pgrp) == 0) {
if (killpg(cmnd_pgrp, SIGCONT) != 0) {
sudo_warn("kill(%d, SIGCONT)",
(int)cmnd_pgrp);
}
close(fd);
continue;
}
}
}
}
}
if (signo == SIGTSTP) {
memset(&sa, 0, sizeof(sa));
sigemptyset(&sa.sa_mask);
sa.sa_flags = SA_RESTART;
sa.sa_handler = SIG_DFL;
if (sudo_sigaction(SIGTSTP, &sa, &osa) != 0) {
sudo_warn(U_("unable to set handler for signal %d"),
SIGTSTP);
}
}
if (kill(getpid(), signo) != 0)
sudo_warn("kill(%d, SIG%s)", (int)getpid(), signame);
if (signo == SIGTSTP) {
if (sudo_sigaction(SIGTSTP, &osa, NULL) != 0) {
sudo_warn(U_("unable to restore handler for signal %d"),
SIGTSTP);
}
}
if (saved_pgrp != -1) {
/*
* On resume, restore foreground process group, if different.
* Otherwise, we cannot resume some shells (pdksh).
*
* It is possible that we are no longer the foreground process,
* use tcsetpgrp_nobg() to prevent sudo from receiving SIGTTOU.
*/
if (saved_pgrp != ec->ppgrp)
tcsetpgrp_nobg(fd, saved_pgrp);
close(fd);
}
/* If the main command is suspended, suspend sudo too. */
if (pid == ec->cmnd_pid)
suspend_sudo_nopty(signo, ec->ppgrp, ec->cmnd_pid);
} else {
if (WIFSIGNALED(status)) {
if (sig2str(WTERMSIG(status), signame) == -1) {