Fix: Handle SIGBUS in sessiond and consumerd

[lttng-tools.git] / src / bin / lttng-sessiond / main.c

diff --git a/src/bin/lttng-sessiond/main.c b/src/bin/lttng-sessiond/main.c
index 1174162aa9ac8df25b4dcfc23994a95ac09e50bb..ee4d0c78ec499800cd5e149c95a02afa4f3a53e4 100644 (file)
--- a/src/bin/lttng-sessiond/main.c
+++ b/src/bin/lttng-sessiond/main.c
@@ -75,6 +75,7 @@
 #include "manage-apps.h"
 #include "manage-kernel.h"
 #include "modprobe.h"
+#include "ust-sigbus.h"
 
 static const char *help_msg =
 #ifdef LTTNG_EMBED_HELP
@@ -1170,7 +1171,7 @@ error:
  * Simply stop all worker threads, leaving main() return gracefully after
  * joining all threads and calling cleanup().
  */
-static void sighandler(int sig)
+static void sighandler(int sig, siginfo_t *siginfo, void *arg)
 {
        switch (sig) {
        case SIGINT:
@@ -1184,6 +1185,23 @@ static void sighandler(int sig)
        case SIGUSR1:
                CMM_STORE_SHARED(recv_child_signal, 1);
                break;
+       case SIGBUS:
+       {
+               int write_ret;
+               const char msg[] = "Received SIGBUS, aborting program.\n";
+
+               lttng_ust_handle_sigbus(siginfo->si_addr);
+               /*
+                * If ustctl did not catch this signal (triggering a
+                * siglongjmp), abort the program. Otherwise, the execution
+                * will resume from the ust-ctl call which caused this error.
+                *
+                * The return value is ignored since the program aborts anyhow.
+                */
+               write_ret = write(STDERR_FILENO, msg, sizeof(msg));
+               (void) write_ret;
+               abort();
+       }
        default:
                break;
        }
@@ -1205,9 +1223,9 @@ static int set_signal_handler(void)
        }
 
        sa.sa_mask = sigset;
-       sa.sa_flags = 0;
+       sa.sa_flags = SA_SIGINFO;
 
-       sa.sa_handler = sighandler;
+       sa.sa_sigaction = sighandler;
        if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) {
                PERROR("sigaction");
                return ret;
@@ -1223,13 +1241,19 @@ static int set_signal_handler(void)
                return ret;
        }
 
+       if ((ret = sigaction(SIGBUS, &sa, NULL)) < 0) {
+               PERROR("sigaction");
+               return ret;
+       }
+
+       sa.sa_flags = 0;
        sa.sa_handler = SIG_IGN;
        if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) {
                PERROR("sigaction");
                return ret;
        }
 
-       DBG("Signal handler set for SIGTERM, SIGUSR1, SIGPIPE and SIGINT");
+       DBG("Signal handler set for SIGTERM, SIGUSR1, SIGPIPE, SIGINT, and SIGBUS");
 
        return ret;
 }