From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39590) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cUPYf-0000W9-SN for qemu-devel@nongnu.org; Thu, 19 Jan 2017 22:08:12 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cUPYe-0002tI-Tv for qemu-devel@nongnu.org; Thu, 19 Jan 2017 22:08:09 -0500 Received: from mx1.redhat.com ([209.132.183.28]:42990) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cUPYe-0002t7-OS for qemu-devel@nongnu.org; Thu, 19 Jan 2017 22:08:08 -0500 From: Jason Wang Date: Fri, 20 Jan 2017 11:07:49 +0800 Message-Id: <1484881670-24237-6-git-send-email-jasowang@redhat.com> In-Reply-To: <1484881670-24237-1-git-send-email-jasowang@redhat.com> References: <1484881670-24237-1-git-send-email-jasowang@redhat.com> Subject: [Qemu-devel] [PULL 5/6] hw/pci: use-after-free in pci_nic_init_nofail when nic device fails to initialize List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: peter.maydell@linaro.org, qemu-devel@nongnu.org Cc: Alex Kompel , Jason Wang From: Alex Kompel 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 , rootbus=0x5555567ed990, default_model=, default_devaddr=) 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=) at vl.c:4481 Signed-off-by: Alex Kompel Signed-off-by: Jason Wang --- 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