su: keep old sigactions in control struct

Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/login-utils/su-common.c b/login-utils/su-common.c
index 589445b3161af9a7ecbcc6122569a871df9c3901..48812cbc11643c79f343d0c8fd4692c136a5575d 100644 (file)
--- a/login-utils/su-common.c
+++ b/login-utils/su-common.c
@@ -99,6 +99,14 @@ enum {
        EXIT_ENOENT = 127
 };
 
+enum {
+       SIGTERM_IDX = 0,
+       SIGINT_IDX,
+       SIGQUIT_IDX,
+
+       SIGNALS_IDX_COUNT
+};
+
 /*
  * su/runuser control struct
  */
@@ -117,6 +125,8 @@ struct su_context {
 
        pid_t           child;                  /* fork() baby */
 
+       struct sigaction oldact[SIGNALS_IDX_COUNT];     /* original sigactions indexed by SIG*_IDX */
+
        unsigned int runuser :1,                /* flase=su, true=runuser */
                     runuser_uopt :1,           /* runuser -u specified */
                     isterm :1,                 /* is stdin terminal? */
@@ -361,14 +371,6 @@ static int wait_for_child(struct su_context *su)
 
 static void create_watching_parent(struct su_context *su)
 {
-       enum {
-               SIGTERM_IDX = 0,
-               SIGINT_IDX,
-               SIGQUIT_IDX,
-
-               SIGNALS_IDX_COUNT
-       };
-       struct sigaction oldact[SIGNALS_IDX_COUNT];
        sigset_t ourset;
        int status;
 
@@ -402,7 +404,6 @@ static void create_watching_parent(struct su_context *su)
         * 1) block all signals
         */
        DBG(SIG, ul_debug("initialize signals"));
-       memset(oldact, 0, sizeof(oldact));
 
        sigfillset(&ourset);
        if (sigprocmask(SIG_BLOCK, &ourset, NULL)) {
@@ -438,8 +439,8 @@ static void create_watching_parent(struct su_context *su)
                /* 3a) set signal handlers (for session) */
                if (!caught_signal
                    && !su->same_session
-                   && (sigaction(SIGINT, &action, &oldact[SIGINT_IDX])
-                      || sigaction(SIGQUIT, &action, &oldact[SIGQUIT_IDX]))) {
+                   && (sigaction(SIGINT, &action, &su->oldact[SIGINT_IDX])
+                      || sigaction(SIGQUIT, &action, &su->oldact[SIGQUIT_IDX]))) {
 
                        warn(_("cannot set signal handler for session"));
                        caught_signal = true;
@@ -447,7 +448,7 @@ static void create_watching_parent(struct su_context *su)
 
                /* 3b) set signal handlers */
                if (!caught_signal
-                    && sigaction(SIGTERM, &action, &oldact[SIGTERM_IDX])) {
+                    && sigaction(SIGTERM, &action, &su->oldact[SIGTERM_IDX])) {
 
                        warn(_("cannot set signal handler"));
                        caught_signal = true;
@@ -494,13 +495,13 @@ static void create_watching_parent(struct su_context *su)
                DBG(SIG, ul_debug("restore signals setting"));
                switch (caught_signal) {
                case SIGTERM:
-                       sigaction(SIGTERM, &oldact[SIGTERM_IDX], NULL);
+                       sigaction(SIGTERM, &su->oldact[SIGTERM_IDX], NULL);
                        break;
                case SIGINT:
-                       sigaction(SIGINT, &oldact[SIGINT_IDX], NULL);
+                       sigaction(SIGINT, &su->oldact[SIGINT_IDX], NULL);
                        break;
                case SIGQUIT:
-                       sigaction(SIGQUIT, &oldact[SIGQUIT_IDX], NULL);
+                       sigaction(SIGQUIT, &su->oldact[SIGQUIT_IDX], NULL);
                        break;
                default:
                        /* just in case that signal stuff initialization failed and