Re: [PATCH] qemu_domain: Partially validate memory amounts when auto-adding NUMA node

When automatically adding a NUMA node (qemuDomainDefNumaAutoAdd()) the memory size of the node is computed as: total_memory - sum(memory devices) And we have a nice helper for that: virDomainDefGetMemoryInitial() so it looks logical to just call it. Except, this code runs in post parse callback, i.e. memory sizes were not validated and it may happen that the sum is greater than the total memory. This would be caught by virDomainDefPostParseMemory() but that runs only after driver specific callbacks (i.e. after qemuDomainDefNumaAutoAdd()) and because the domain config was changed and memory was increased to this huge number no error is caught. So let's do what virDomainDefGetMemoryInitial() would do, but with error checking. Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2216236 Fixes: f5d4f5c8ee44e9f1939070afcc5381bdd5545e50 Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com&gt; --- src/qemu/qemu_domain.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/src/qemu/qemu_domain.c b/src/qemu/qemu_domain.c index 6eea8a9fa5..fdda001795 100644 --- a/src/qemu/qemu_domain.c +++ b/src/qemu/qemu_domain.c @@ -4821,17 +4821,24 @@ qemuDomainDefNumaAutoAdd(virDomainDef *def, return 0; } - initialMem = virDomainDefGetMemoryInitial(def); + initialMem = virDomainDefGetMemoryTotal(def);

if (!def->numa) def->numa = virDomainNumaNew(); virDomainNumaSetNodeCount(def->numa, 1); - virDomainNumaSetNodeMemorySize(def->numa, 0, initialMem); for (i = 0; i < def->nmems; i++) { virDomainMemoryDef *mem = def->mems[i]; + if (mem->size > initialMem) { + virReportError(VIR_ERR_XML_ERROR, "%s", + _("Total size of memory devices exceeds the total memory size")); + return -1; + } + + initialMem -= mem->size; + switch (mem->model) { case VIR_DOMAIN_MEMORY_MODEL_DIMM: case VIR_DOMAIN_MEMORY_MODEL_NVDIMM: @@ -4848,6 +4855,8 @@ qemuDomainDefNumaAutoAdd(virDomainDef *def, } } + virDomainNumaSetNodeMemorySize(def->numa, 0, initialMem); + return 0; } -- 2.41.0