Re: [libvirt] [PATCH 02/12] storage: avoid mishandling backing store > 2GB

2011/6/6 Eric Blake <eblake(a)redhat.com&gt;: > Detected by Coverity. The code was doing math on shifted unsigned > char (which promotes to int), then promoting that to unsigned long > during assignment to size. On 64-bit platforms, this risks sign > extending values of size > 2GiB. Bug present since commit > 489fd3 (v0.6.0).

> > +#include <stdint.h> > #ifdef __linux__ > # if HAVE_LINUX_MAGIC_H > # include <linux/magic.h> > @@ -274,7 +275,7 @@ qcowXGetBackingStore(char **res, > bool isQCow2) > { > unsigned long long offset; > - unsigned long size; > + uint32_t size; > > *res = NULL; > if (format) Using unsigned int instead of uint32_t would also work and avoid stdint.h types that the libvirt codebase avoids.