X-Git-Url: https://ruderich.org/simon/gitweb/?p=ptyas%2Fptyas.git;a=blobdiff_plain;f=ptyas.c;h=c21c6ae35036af64b627aebf583d5980518ae5a7;hp=ab99f8ede71cf352d4d7aa2ef9c2af83a5b4ef06;hb=7b101456491c5fcaa5b7f275bef98fe8fe012273;hpb=c8ffdb4777654018284c63d7824efca50e5d65b7 diff --git a/ptyas.c b/ptyas.c index ab99f8e..c21c6ae 100644 --- a/ptyas.c +++ b/ptyas.c @@ -217,14 +217,13 @@ static void proxy_input_between_ttys(int pty_master, int ctty, volatile pid_t *p if (ppoll(fds, nfds, NULL /* no timeout */, &sigset_old) == -1) { if (errno == EAGAIN || errno == EINTR) { continue; - } else { - perror("poll"); } + perror("poll"); break; } /* Handle errors first. (Data available before the error occurred - * might be skipped, but shouldn't matter here.) */ + * might be dropped, but shouldn't matter here.) */ if (fds[0].revents & (POLLERR | POLLNVAL)) { fprintf(stderr, "poll: error on master: %d\n", fds[0].revents); break; @@ -360,6 +359,9 @@ int main(int argc, char **argv) { if (pid == -1) { die("fork child"); } else if (pid == 0) { + /* Drop the privileges just now so that the other user doesn't get + * access to the master TTY or the session leader (which might + * have additional privileges). */ drop_privileges_or_die(uid, gid); dup2_or_die(pty_slave, STDIN_FILENO); @@ -442,7 +444,7 @@ int main(int argc, char **argv) { die("tcsetattr restore"); } - /* Wait until we got the status code from our child. poll() might also + /* Wait until we got the status code from our child. poll() might already * exit after POLLHUP while we haven't collected the child yet. */ if (sigprocmask(SIG_BLOCK, &sigset, &sigset_old) != 0) { die("sigprocmask block sigchld loop");