Paolo Bonzini <pbonz...@redhat.com> 于2018年11月16日周五 下午5:31写道:
> Because the CMB BAR has a min_access_size of 2, if you read the last > byte it will try to memcpy *2* bytes from n->cmbuf, causing an off-by-one > error. This is CVE-2018-16847. > > Another way to fix this might be to register the CMB as a RAM memory > region, which would also be more efficient. However, that might be a > change for big-endian machines; I didn't think this through and I don't > know how real hardware works. Add a basic testcase for the CMB in case > somebody does this change later on. > > Cc: Keith Busch <keith.bu...@intel.com> > Cc: qemu-block@nongnu.org > Cc: Li Qiang <liq...@gmail.com> > Signed-off-by: Paolo Bonzini <pbonz...@redhat.com> --- > hw/block/nvme.c | 2 +- > tests/Makefile.include | 2 +- > tests/nvme-test.c | 58 +++++++++++++++++++++++++++++++++++++++--- > 3 files changed, 57 insertions(+), 5 deletions(-) > > diff --git a/hw/block/nvme.c b/hw/block/nvme.c > index 09d7c90259..5d92794ef7 100644 > --- a/hw/block/nvme.c > +++ b/hw/block/nvme.c > @@ -1192,7 +1192,7 @@ static const MemoryRegionOps nvme_cmb_ops = { > .write = nvme_cmb_write, > .endianness = DEVICE_LITTLE_ENDIAN, > .impl = { > - .min_access_size = 2, > + .min_access_size = 1, > .max_access_size = 8, > }, > }; > diff --git a/tests/Makefile.include b/tests/Makefile.include > index 613242bc6e..fb0b449c02 100644 > --- a/tests/Makefile.include > +++ b/tests/Makefile.include > @@ -730,7 +730,7 @@ tests/test-hmp$(EXESUF): tests/test-hmp.o > tests/machine-none-test$(EXESUF): tests/machine-none-test.o > tests/drive_del-test$(EXESUF): tests/drive_del-test.o > $(libqos-virtio-obj-y) > tests/qdev-monitor-test$(EXESUF): tests/qdev-monitor-test.o > $(libqos-pc-obj-y) > -tests/nvme-test$(EXESUF): tests/nvme-test.o > +tests/nvme-test$(EXESUF): tests/nvme-test.o $(libqos-pc-obj-y) > tests/pvpanic-test$(EXESUF): tests/pvpanic-test.o > tests/i82801b11-test$(EXESUF): tests/i82801b11-test.o > tests/ac97-test$(EXESUF): tests/ac97-test.o > diff --git a/tests/nvme-test.c b/tests/nvme-test.c > index 7674a446e4..2abb3b6d19 100644 > --- a/tests/nvme-test.c > +++ b/tests/nvme-test.c > @@ -8,11 +8,64 @@ > */ > > #include "qemu/osdep.h" > +#include "qemu/units.h" > #include "libqtest.h" > +#include "libqos/libqos-pc.h" > + > +static QOSState *qnvme_start(const char *extra_opts) > +{ > + QOSState *qs; > + const char *arch = qtest_get_arch(); > + const char *cmd = "-drive id=drv0,if=none,file=null-co://,format=raw " > + "-device nvme,addr=0x4.0,serial=foo,drive=drv0 %s"; > + > + if (strcmp(arch, "i386") == 0 || strcmp(arch, "x86_64") == 0) { > + qs = qtest_pc_boot(cmd, extra_opts ? : ""); > + global_qtest = qs->qts; > + return qs; > + } > + > + g_printerr("nvme tests are only available on x86\n"); > + exit(EXIT_FAILURE); > +} > + > +static void qnvme_stop(QOSState *qs) > +{ > + qtest_shutdown(qs); > +} > > -/* Tests only initialization so far. TODO: Replace with functional tests > */ > static void nop(void) > { > + QOSState *qs; > + > + qs = qnvme_start(NULL); > + qnvme_stop(qs); > +} > + > +static void nvmetest_cmb_test(void) > +{ > + const int cmb_bar_size = 2 * MiB; > + QOSState *qs; > + QPCIDevice *pdev; > + QPCIBar bar; > + > + qs = qnvme_start("-global nvme.cmb_size_mb=2"); > + pdev = qpci_device_find(qs->pcibus, QPCI_DEVFN(4,0)); > + g_assert(pdev != NULL); > + > + qpci_device_enable(pdev); > + bar = qpci_iomap(pdev, 2, NULL); > + > + qpci_io_writel(pdev, bar, 0, 0xccbbaa99); > + g_assert_cmpint(qpci_io_readb(pdev, bar, 0), ==, 0x99); > + g_assert_cmpint(qpci_io_readw(pdev, bar, 0), ==, 0xaa99); > + > + /* Test partially out-of-bounds accesses. */ > + qpci_io_writel(pdev, bar, cmb_bar_size - 1, 0x44332211); > + g_assert_cmpint(qpci_io_readb(pdev, bar, cmb_bar_size - 1), ==, 0x11); > + g_assert_cmpint(qpci_io_readw(pdev, bar, cmb_bar_size - 1), !=, > 0x2211); > + g_assert_cmpint(qpci_io_readl(pdev, bar, cmb_bar_size - 1), !=, > 0x44332211); > Here seems need a g_free(pdev), > + qnvme_stop(qs); > } > > int main(int argc, char **argv) > @@ -21,9 +74,8 @@ int main(int argc, char **argv) > > g_test_init(&argc, &argv, NULL); > qtest_add_func("/nvme/nop", nop); > + qtest_add_func("/nvme/cmb_test", nvmetest_cmb_test); > > - qtest_start("-drive id=drv0,if=none,file=null-co://,format=raw " > - "-device nvme,drive=drv0,serial=foo"); > ret = g_test_run(); > > qtest_end(); > There is no qtest_start(), this qtest_end() seems trigger an assert in glib. (tests/nvme-test:44053): GLib-CRITICAL **: g_hook_destroy_link: assertion 'hook != NULL' failed Otherwise Reviewed-by: Li Qiang <liq...@gmail.com> Tested-by: Li Qiang <liq...@gmail.com> Thanks, Li Qiang > -- > 2.19.1 > >