From 87176d0ce95bfdf2091c93cc30f44687be481185 Mon Sep 17 00:00:00 2001 From: Ryota Ozaki Date: Fri, 1 Nov 2013 00:45:12 +0900 Subject: [PATCH] nodedev_hal: fix segfault when virDBusGetSystemBus fails Thie patch fixes the segfault: error : nodeStateInitialize:658 : DBus not available, disabling HAL driver: internal error: Unable to get DBus system bus connection: Failed to connect to socket /var/run/dbus/system_bus_socket: No such file or directory error : nodeStateInitialize:719 : ?: Caught Segmentation violation dumping internal log buffer: This segfault occurs at the below VIR_ERROR: failure: if (dbus_error_is_set(&err)) { VIR_ERROR(_("%s: %s"), err.name, err.message); When virDBusGetSystemBus fails, the code jumps to the above failure path. However, the err variable is not correctly initialized before calling virDBusGetSystemBus. As a result, dbus_error_is_set may pass over the uninitialized err variable whose name or message may point to somewhere unknown memory region, which causes a segfault on VIR_ERROR. The new code initializes the err variable before calling virDBusGetSystemBus. Signed-off-by: Ryota Ozaki --- src/node_device/node_device_hal.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/node_device/node_device_hal.c b/src/node_device/node_device_hal.c index d94767c327..a019a07436 100644 --- a/src/node_device/node_device_hal.c +++ b/src/node_device/node_device_hal.c @@ -652,6 +652,7 @@ nodeStateInitialize(bool privileged ATTRIBUTE_UNUSED, } nodeDeviceLock(driverState); + dbus_error_init(&err); if (!(sysbus = virDBusGetSystemBus())) { virErrorPtr verr = virGetLastError(); VIR_ERROR(_("DBus not available, disabling HAL driver: %s"), @@ -660,7 +661,6 @@ nodeStateInitialize(bool privileged ATTRIBUTE_UNUSED, goto failure; } - dbus_error_init(&err); hal_ctx = libhal_ctx_new(); if (hal_ctx == NULL) { VIR_ERROR(_("libhal_ctx_new returned NULL"));