Fix segmentation fault when qemu_signal_init fails

When qemu_signal_init() fails in qemu_init_main_loop(), we return
without setting an error.  Its callers crash then when they try to
report the error with error_report_err().

To avoid such segmentation fault, add a new Error parameter to make
the call trace to propagate the err to the final caller.

Fixes: 2f78e491d7b46542158ce0b8132ee4e05bc0ade4
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Fei Li <fli@suse.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20190113140849.38339-2-lifei1214@126.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

diff --git a/util/main-loop.c b/util/main-loop.c
index affe040..443cb4c 100644 (file)
--- a/util/main-loop.c
+++ b/util/main-loop.c
@@ -71,7 +71,7 @@ static void sigfd_handler(void *opaque)
     }
 }
 
-static int qemu_signal_init(void)
+static int qemu_signal_init(Error **errp)
 {
     int sigfd;
     sigset_t set;
@@ -96,7 +96,7 @@ static int qemu_signal_init(void)
     sigdelset(&set, SIG_IPI);
     sigfd = qemu_signalfd(&set);
     if (sigfd == -1) {
-        fprintf(stderr, "failed to create signalfd\n");
+        error_setg_errno(errp, errno, "failed to create signalfd");
         return -errno;
     }
 
@@ -109,7 +109,7 @@ static int qemu_signal_init(void)
 
 #else /* _WIN32 */
 
-static int qemu_signal_init(void)
+static int qemu_signal_init(Error **errp)
 {
     return 0;
 }
@@ -148,7 +148,7 @@ int qemu_init_main_loop(Error **errp)
 
     init_clocks(qemu_timer_notify_cb);
 
-    ret = qemu_signal_init();
+    ret = qemu_signal_init(errp);
     if (ret) {
         return ret;
     }