[PATCH] serialize access pci_get_strings function with a mutex

serialize access pci_get_strings function with a mutex. nodedev-init thread: nodeStateInitializeEnumerate -> udevEnumerateDevices-> udevProcessDeviceListEntry -> udevAddOneDevice -> udevGetDeviceDetails-> udevProcessPCI -> udevTranslatePCIIds -> pci_get_strings -> (libpciaccess) find_device_name -> populate_vendor -> d = realloc( vend->devices, (vend->num_devices + 1), * sizeof( struct pci_device_leaf ) ); vend->num_devices++; udev-event thread: udevEventHandleThread -> udevHandleOneDevice -> udevAddOneDevice-> udevGetDeviceDetails-> udevProcessPCI -> udevTranslatePCIIds -> pci_get_strings -> (libpciaccess) find_device_name -> populate_vendor -> d = realloc( vend->devices, (vend->num_devices + 1), * sizeof( struct pci_device_leaf ) ); vend->num_devices++; Since the functions provided by libpciaccess are not thread-safe, when the udev-event and nodedev-init threads of libvirt call the pci_get_strings function provided by libpaciaccess at the same time. It will appear that for the same address, realloc a large space first, and then realloc a small space, which triggers the 'invalid next size' of realloc, leading to the thread core. Signed-off-by: WangJian <wangjian161(a)huawei.com&gt; --- src/node_device/node_device_udev.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/src/node_device/node_device_udev.c b/src/node_device/node_device_udev.c index 3f28858..cc752ba 100644 --- a/src/node_device/node_device_udev.c +++ b/src/node_device/node_device_udev.c @@ -331,6 +331,7 @@ udevGenerateDeviceName(struct udev_device *device, return 0; } +static pthread_mutex_t g_pciaccess_mutex = PTHREAD_MUTEX_INITIALIZER; static int udevTranslatePCIIds(unsigned int vendor, @@ -350,11 +351,13 @@ udevTranslatePCIIds(unsigned int vendor, m.match_data = 0; /* pci_get_strings returns void */ + pthread_mutex_lock(&g_pciaccess_mutex); pci_get_strings(&m, &device_name, &vendor_name, NULL, NULL); + pthread_mutex_unlock(&g_pciaccess_mutex); *vendor_string = g_strdup(vendor_name); *product_string = g_strdup(device_name); -- 2.23.0