Re: [libvirt] [PATCH] node_device: Check return value for udev_new()

On Wed, Nov 30, 2016 at 04:25 PM +0100, Martin Kletzander <mkletzan(a)redhat.com&gt; wrote: > On Wed, Nov 30, 2016 at 01:45:32PM +0100, Marc Hartmayer wrote: >>The comment was actually wrong as >>https://www.freedesktop.org/software/systemd/man/udev_new.html >>mentions that on failure NULL is returned. >> >>Signed-off-by: Marc Hartmayer <mhartmay(a)linux.vnet.ibm.com&gt; >>Reviewed-by: Bjoern Walk <bwalk(a)linux.vnet.ibm.com&gt; >>Reviewed-by: Boris Fiuczynski <fiuczy(a)linux.vnet.ibm.com&gt; >>--- >> src/node_device/node_device_udev.c | 10 ++++------ >> 1 file changed, 4 insertions(+), 6 deletions(-) >> >>diff --git a/src/node_device/node_device_udev.c b/src/node_device/node_device_udev.c >>index 4b81312..4b0a875 100644 >>--- a/src/node_device/node_device_udev.c >>+++ b/src/node_device/node_device_udev.c >>@@ -1491,13 +1491,11 @@ static int nodeStateInitialize(bool privileged, >> if (udevPCITranslateInit(privileged) < 0) >> goto cleanup; >> >>- /* >>- * http://www.kernel.org/pub/linux/utils/kernel/hotplug/libudev/libudev-udev... >>- * >>- * indicates no return value other than success, so we don't check >>- * its return value. >>- */ >> udev = udev_new(); >>+ if (!udev) { >>+ virReportOOMError(); >>+ goto cleanup; >>+ } > > Is that true for other udevs and not just systemd-udev? I'm not sure about other versions of udev but the NULL pointer is already handled in udevStatInitialize() for udev_new() in a likewise manner. > Does it really mean just an OOM error? It fails for systemd-udev if malloc/calloc fails => this is most likely a OOM error at this point. > Couldn't we add a proper error message? In udevStateInitialize() the error handling reports an internal error but as the original error is caused by OOM I think we have to use virReportOOMError().

-- Beste Grüße / Kind regards Marc Hartmayer IBM Deutschland Research & Development GmbH Vorsitzende des Aufsichtsrats: Martina Koederitz Geschäftsführung: Dirk Wittkopp Sitz der Gesellschaft: Böblingen Registergericht: Amtsgericht Stuttgart, HRB 243294