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qrexec: don't wait indefinitely if the daemon startup failed

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Count started children and if the last one exits before getting SIGUSR1
(confirmation of successful daemon startup) report failure.
This commit is contained in:
Marek Marczykowski-Górecki 2013-10-27 16:03:33 +01:00
parent 9f62349732
commit ce971eaa54
1 changed files with 18 additions and 6 deletions
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24
qrexec/qrexec-daemon.c
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@ -61,12 +61,28 @@ char *default_user = "user";
char default_user_keyword[] = "DEFAULT:"; char default_user_keyword[] = "DEFAULT:";
#define default_user_keyword_len_without_colon (sizeof(default_user_keyword)-2) #define default_user_keyword_len_without_colon (sizeof(default_user_keyword)-2)
/*
we need to track the number of children, so that excessive QREXEC_EXECUTE_*
commands do not fork-bomb dom0
*/
int children_count;
void sigusr1_handler(int x) void sigusr1_handler(int x)
{ {
fprintf(stderr, "connected\n"); fprintf(stderr, "connected\n");
exit(0); exit(0);
} }
void sigchld_parent_handler(int x)
{
children_count--;
/* starting value is 0 so we see dead real qrexec-daemon as -1 */
if (children_count < 0) {
fprintf(stderr, "failed\n");
exit(1);
}
}
void sigchld_handler(int x); void sigchld_handler(int x);
char *remote_domain_name; // guess what char *remote_domain_name; // guess what
@ -103,6 +119,7 @@ int ask_on_connect_timeout(int xid, int timeout)
remote_domain_name, timeout); remote_domain_name, timeout);
#undef KDIALOG_CMD #undef KDIALOG_CMD
#undef ZENITY_CMD #undef ZENITY_CMD
children_count++;
ret = system(text); ret = system(text);
ret = WEXITSTATUS(ret); ret = WEXITSTATUS(ret);
// fprintf(stderr, "ret=%d\n", ret); // fprintf(stderr, "ret=%d\n", ret);
@ -140,6 +157,7 @@ void init(int xid)
startup_timeout = MAX_STARTUP_TIME_DEFAULT; startup_timeout = MAX_STARTUP_TIME_DEFAULT;
} }
signal(SIGUSR1, sigusr1_handler); signal(SIGUSR1, sigusr1_handler);
signal(SIGCHLD, sigchld_parent_handler);
switch (pid=fork()) { switch (pid=fork()) {
case -1: case -1:
perror("fork"); perror("fork");
@ -210,12 +228,6 @@ void handle_new_client()
max_client_fd = fd; max_client_fd = fd;
} }
/*
we need to track the number of children, so that excessive QREXEC_EXECUTE_*
commands do not fork-bomb dom0
*/
int children_count;
void terminate_client_and_flush_data(int fd) void terminate_client_and_flush_data(int fd)
{ {
int i; int i;