execute: only reset those signals to the default we really need to reset to the default

5 files changed, 62 insertions, 12 deletions

diff --git a/src/execute.c b/src/execute.c
index 06eb15215d..ead6c0fa42 100644
--- a/src/execute.c
+++ b/src/execute.c
@@ -783,7 +783,11 @@ int exec_spawn(ExecCommand *command,
 
                 /* child */
 
-                reset_all_signal_handlers();
+                /* We reset exactly these two signals, since they are
+                 * the only ones we set to SIG_IGN in the main
+                 * daemon. All others */
+                default_signals(SIGNALS_CRASH_HANLDER,
+                                SIGNALS_IGNORE, -1);
 
                 if (sigemptyset(&ss) < 0 ||
                     sigprocmask(SIG_SETMASK, &ss, NULL) < 0) {
diff --git a/src/execute.h b/src/execute.h
index d42e0ba9d9..045d4620d7 100644
--- a/src/execute.h
+++ b/src/execute.h
@@ -41,6 +41,10 @@ struct CGroupBonding;
 /* Abstract namespace! */
 #define LOGGER_SOCKET "/org/freedesktop/systemd1/logger"
 
+/* This doesn't really belong here, but I couldn't find a better place to put this. */
+#define SIGNALS_CRASH_HANLDER SIGSEGV,SIGILL,SIGFPE,SIGBUS,SIGQUIT,SIGABRT
+#define SIGNALS_IGNORE SIGKILL,SIGPIPE
+
 typedef enum ExecInput {
         EXEC_INPUT_NULL,
         EXEC_INPUT_TTY,
diff --git a/src/main.c b/src/main.c
index 95d2115230..5c2af042d9 100644
--- a/src/main.c
+++ b/src/main.c
@@ -165,12 +165,7 @@ static void install_crash_handler(void) {
         sa.sa_handler = crash;
         sa.sa_flags = SA_NODEFER;
 
-        assert_se(sigaction(SIGSEGV, &sa, NULL) == 0);
-        assert_se(sigaction(SIGILL, &sa, NULL) == 0);
-        assert_se(sigaction(SIGFPE, &sa, NULL) == 0);
-        assert_se(sigaction(SIGBUS, &sa, NULL) == 0);
-        assert_se(sigaction(SIGQUIT, &sa, NULL) == 0);
-        assert_se(sigaction(SIGABRT, &sa, NULL) == 0);
+        sigaction_many(&sa, SIGNALS_CRASH_HANLDER, -1);
 }
 
 static int make_null_stdio(void) {
@@ -569,8 +564,7 @@ int main(int argc, char *argv[]) {
         assert_se(reset_all_signal_handlers() == 0);
 
         /* If we are init, we can block sigkill. Yay. */
-        ignore_signal(SIGKILL);
-        ignore_signal(SIGPIPE);
+        ignore_signals(SIGNALS_IGNORE, -1);
 
         if (running_as != MANAGER_SESSION)
                 if (parse_proc_cmdline() < 0)
diff --git a/src/util.c b/src/util.c
index 5c1e16ab6e..47b1b443ff 100644
--- a/src/util.c
+++ b/src/util.c
@@ -1735,14 +1735,59 @@ int release_terminal(void) {
         return r;
 }
 
-int ignore_signal(int sig) {
+int sigaction_many(const struct sigaction *sa, ...) {
+        va_list ap;
+        int r = 0, sig;
+
+        va_start(ap, sa);
+        while ((sig = va_arg(ap, int)) > 0)
+                if (sigaction(sig, sa, NULL) < 0)
+                        r = -errno;
+        va_end(ap);
+
+        return r;
+}
+
+int ignore_signals(int sig, ...) {
         struct sigaction sa;
+        va_list ap;
+        int r = 0;
 
         zero(sa);
         sa.sa_handler = SIG_IGN;
         sa.sa_flags = SA_RESTART;
 
-        return sigaction(sig, &sa, NULL);
+        if (sigaction(sig, &sa, NULL) < 0)
+                r = -errno;
+
+        va_start(ap, sig);
+        while ((sig = va_arg(ap, int)) > 0)
+                if (sigaction(sig, &sa, NULL) < 0)
+                        r = -errno;
+        va_end(ap);
+
+        return r;
+}
+
+int default_signals(int sig, ...) {
+        struct sigaction sa;
+        va_list ap;
+        int r = 0;
+
+        zero(sa);
+        sa.sa_handler = SIG_DFL;
+        sa.sa_flags = SA_RESTART;
+
+        if (sigaction(sig, &sa, NULL) < 0)
+                r = -errno;
+
+        va_start(ap, sig);
+        while ((sig = va_arg(ap, int)) > 0)
+                if (sigaction(sig, &sa, NULL) < 0)
+                        r = -errno;
+        va_end(ap);
+
+        return r;
 }
 
 int close_pipe(int p[]) {
diff --git a/src/util.h b/src/util.h
index 84dd2bc8d1..93d67081b7 100644
--- a/src/util.h
+++ b/src/util.h
@@ -28,6 +28,7 @@
 #include <stdbool.h>
 #include <stdlib.h>
 #include <stdio.h>
+#include <signal.h>
 
 typedef uint64_t usec_t;
 
@@ -223,7 +224,9 @@ int release_terminal(void);
 
 int flush_fd(int fd);
 
-int ignore_signal(int sig);
+int ignore_signals(int sig, ...);
+int default_signals(int sig, ...);
+int sigaction_many(const struct sigaction *sa, ...);
 
 int close_pipe(int p[]);