[libvirt] [PATCH 1/2] qemu-JSON: Error out if number is out of range instead of overflowing to negative

Commit 78eb8b60d59662271c4a9a1be8c9002ee84dc8cf works around qemu's inability to parse unsigned 64 bit integers by representing them as signed. This introduces a bug where if the requested integer is greater than LLONG_MAX the result is wrapped to negative numbers. This patch adds a check to avoid the wrap for unsigned numbers and error out rather than passing them along. --- src/qemu/qemu_monitor_json.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) diff --git a/src/qemu/qemu_monitor_json.c b/src/qemu/qemu_monitor_json.c index 1bf8baf..6cc21ee 100644 --- a/src/qemu/qemu_monitor_json.c +++ b/src/qemu/qemu_monitor_json.c @@ -460,10 +460,16 @@ qemuMonitorJSONMakeCommandRaw(bool wrap, const char *cmdname, ...) case 'U': { /* qemu silently truncates numbers larger than LLONG_MAX, * so passing the full range of unsigned 64 bit integers - * is not safe here. Pass them as signed 64 bit integers - * instead. + * is not safe here. Limit them to LLONG_MAX. */ long long val = va_arg(args, long long); + if (val < 0) { + virReportError(VIR_ERR_OVERFLOW, + _("Value of '%s' can't be represented in JSON: " + "value too big (%llu > %lld)"), + key, val, LLONG_MAX); + goto error; + } ret = virJSONValueObjectAppendNumberLong(jargs, key, val); } break; case 'd': { -- 1.8.1.5