qga: handle possible SIGPIPE in guest-file-write

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>
This commit is contained in:
Denis V. Lunev 2015-10-13 18:41:21 +03:00 committed by Michael Roth
parent d697e30cff
commit 4005b4732e
2 changed files with 23 additions and 1 deletions

View file

@ -225,6 +225,22 @@ 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,
@ -250,7 +266,7 @@ 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);

View file

@ -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;
}