From: Alex Kompel <bar...@gmail.com> object_property_set_bool(OBJECT(dev), true, "realized", &err) in pci_nic_init_nofail may release the object if device fails to initialize which leads to use-after-free in error handling block. qdev_init_nofail does the same thing while holding the reference.
(gdb) run -net nic qemu-system-x86_64: failed to find romfile "efi-e1000.rom" Program received signal SIGSEGV, Segmentation fault. object_unparent (obj=0x7fffe96a0010) at qom/object.c:440 440 in qom/object.c (gdb) bt <nd_table>, rootbus=0x5555567ed990, default_model=<optimized out>, default_devaddr=<optimized out>) at hw/pci/pci.c:1812 pci_bus=0x5555567ed990) at hw/i386/pc.c:1634 pci_type=0x555555c1a523 "i440FX", host_type=0x555555ba564e "i440FX-pcihost") at hw/i386/pc_piix.c:241 out>, envp=<optimized out>) at vl.c:4481 Signed-off-by: Alex Kompel <bar...@gmail.com> Signed-off-by: Jason Wang <jasow...@redhat.com> --- hw/pci/pci.c | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-) diff --git a/hw/pci/pci.c b/hw/pci/pci.c index 637d545..fe9acec 100644 --- a/hw/pci/pci.c +++ b/hw/pci/pci.c @@ -1779,7 +1779,6 @@ PCIDevice *pci_nic_init_nofail(NICInfo *nd, PCIBus *rootbus, const char *default_devaddr) { const char *devaddr = nd->devaddr ? nd->devaddr : default_devaddr; - Error *err = NULL; PCIBus *bus; PCIDevice *pci_dev; DeviceState *dev; @@ -1805,13 +1804,7 @@ PCIDevice *pci_nic_init_nofail(NICInfo *nd, PCIBus *rootbus, pci_dev = pci_create(bus, devfn, pci_nic_names[i]); dev = &pci_dev->qdev; qdev_set_nic_properties(dev, nd); - - object_property_set_bool(OBJECT(dev), true, "realized", &err); - if (err) { - error_report_err(err); - object_unparent(OBJECT(dev)); - exit(1); - } + qdev_init_nofail(dev); return pci_dev; } -- 2.7.4