On Wed, Jan 04, 2012 at 03:53:19PM +0800, ajia@redhat.com wrote:
From: Alex Jia <ajia@redhat.com>
It's a NULL pointer deref issue, which leads to libvirtd crash. This patch directly use 'params[i].value.s' value instead of derefing a NULL pointer on memcpy.
* how to reproduce? % virsh numatune <domain> --nodeset 0
The domain must have no nodeset set previously (to crash in this example).
% service libvirtd status
* src/qemu/qemu_driver.c (qemuDomainSetNumaParameters): avoid a NULL pointer deref.
RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=771562
Signed-off-by: Alex Jia <ajia@redhat.com> --- src/qemu/qemu_driver.c | 6 ++---- 1 files changed, 2 insertions(+), 4 deletions(-)
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index 82bab67..1bd93f6 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -6721,14 +6721,12 @@ qemuDomainSetNumaParameters(virDomainPtr dom, }
if (flags & VIR_DOMAIN_AFFECT_CONFIG) { - memcpy(oldnodemask, persistentDef->numatune.memory.nodemask, - VIR_DOMAIN_CPUMASK_LEN); + memcpy(oldnodemask, params[i].value.s, VIR_DOMAIN_CPUMASK_LEN); if (virDomainCpuSetParse(params[i].value.s, 0, persistentDef->numatune.memory.nodemask,
Not correct. In this case persistentDef->numatune.memory.nodemask is null, and virDomainCpuSetParse will always fail, thus the nodeset will never be set.
VIR_DOMAIN_CPUMASK_LEN) < 0) { - memcpy(persistentDef->numatune.memory.nodemask, - oldnodemask, VIR_DOMAIN_CPUMASK_LEN); + memcpy(params[i].value.s, oldnodemask, VIR_DOMAIN_CPUMASK_LEN); ret = -1; continue; }
From f2fe7c7d0041779895330416dca6ac97fcbec88a Mon Sep 17 00:00:00 2001 From: Hu Tao <hutao@cn.fujitsu.com> Date: Wed, 4 Jan 2012 17:00:27 +0800 Subject: [PATCH] qemu: fix a bug in numatune
When setting numa nodeset for a domain which has no nodeset set before, libvirtd crashes by dereferring the pointer to the old nodemask which is null in the case. --- src/qemu/qemu_driver.c | 22 ++++++++++++++++++---- 1 files changed, 18 insertions(+), 4 deletions(-) diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c index 82bab67..37330b4 100644 --- a/src/qemu/qemu_driver.c +++ b/src/qemu/qemu_driver.c @@ -6721,14 +6721,28 @@ qemuDomainSetNumaParameters(virDomainPtr dom, } if (flags & VIR_DOMAIN_AFFECT_CONFIG) { - memcpy(oldnodemask, persistentDef->numatune.memory.nodemask, - VIR_DOMAIN_CPUMASK_LEN); + bool savedmask = false; + if (!persistentDef->numatune.memory.nodemask) { + if (VIR_ALLOC_N(persistentDef->numatune.memory.nodemask, + VIR_DOMAIN_CPUMASK_LEN) < 0) { + virReportOOMError(); + ret = -1; + goto cleanup; + } + } else { + memcpy(oldnodemask, persistentDef->numatune.memory.nodemask, + VIR_DOMAIN_CPUMASK_LEN); + savedmask = true; + } if (virDomainCpuSetParse(params[i].value.s, 0, persistentDef->numatune.memory.nodemask, VIR_DOMAIN_CPUMASK_LEN) < 0) { - memcpy(persistentDef->numatune.memory.nodemask, - oldnodemask, VIR_DOMAIN_CPUMASK_LEN); + if (savedmask) + memcpy(persistentDef->numatune.memory.nodemask, + oldnodemask, VIR_DOMAIN_CPUMASK_LEN); + else + VIR_FREE(persistentDef->numatune.memory.nodemask); ret = -1; continue; } -- 1.7.4.4 -- Thanks, Hu Tao