diff mbox

[10/12] qga: handle possible SIGPIPE in guest-file-write

Message ID 1444925118-10629-11-git-send-email-mdroth@linux.vnet.ibm.com
State New
Headers show

Commit Message

Michael Roth Oct. 15, 2015, 4:05 p.m. UTC 
From: "Denis V. Lunev" <den@openvz.org>

qemu-ga should not exit on guest-file-write to pipe without read end
but proper error code should be returned. The behavior of the
spawned process should be default thus SIGPIPE processing should be
reset to default after fork() but before exec().

Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Yuri Pudgorodskiy <yur@virtuozzo.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
 qga/commands.c | 18 +++++++++++++++++-
 qga/main.c     |  6 ++++++
 2 files changed, 23 insertions(+), 1 deletion(-)
diff mbox

Patch

diff --git a/qga/commands.c b/qga/commands.c
index abd21fc..b23929d 100644
--- a/qga/commands.c
+++ b/qga/commands.c
@@ -214,6 +214,22 @@  static void guest_exec_child_watch(GPid pid, gint status, gpointer data)
     g_spawn_close_pid(pid);
 }
 
+/** Reset ignored signals back to default. */
+static void guest_exec_task_setup(gpointer data)
+{
+#if !defined(G_OS_WIN32)
+    struct sigaction sigact;
+
+    memset(&sigact, 0, sizeof(struct sigaction));
+    sigact.sa_handler = SIG_DFL;
+
+    if (sigaction(SIGPIPE, &sigact, NULL) != 0) {
+        slog("sigaction() failed to reset child process's SIGPIPE: %s",
+             strerror(errno));
+    }
+#endif
+}
+
 GuestExec *qmp_guest_exec(const char *path,
                        bool has_arg, strList *arg,
                        bool has_env, strList *env,
@@ -239,7 +255,7 @@  GuestExec *qmp_guest_exec(const char *path,
             G_SPAWN_SEARCH_PATH |
             G_SPAWN_DO_NOT_REAP_CHILD |
             G_SPAWN_STDOUT_TO_DEV_NULL | G_SPAWN_STDERR_TO_DEV_NULL,
-            NULL, NULL, &pid, NULL, NULL, NULL, &gerr);
+            guest_exec_task_setup, NULL, &pid, NULL, NULL, NULL, &gerr);
     if (!ret) {
         error_setg(err, QERR_QGA_COMMAND_FAILED, gerr->message);
         g_error_free(gerr);
diff --git a/qga/main.c b/qga/main.c
index aa6a063..068169f 100644
--- a/qga/main.c
+++ b/qga/main.c
@@ -161,6 +161,12 @@  static gboolean register_signal_handlers(void)
         g_error("error configuring signal handler: %s", strerror(errno));
     }
 
+    sigact.sa_handler = SIG_IGN;
+    if (sigaction(SIGPIPE, &sigact, NULL) != 0) {
+        g_error("error configuring SIGPIPE signal handler: %s",
+                strerror(errno));
+    }
+
     return true;
 }