Re: [libvirt] [PATCH 4/9] virutil: Resolve Coverity RESOURCE_LEAK

[adding gnulib, in case anyone else runs into the same false positive] On 09/11/2014 06:06 PM, John Ferlan wrote: ACK. More details that we worked out on IRC: the mgetgroups code gets a list that may contain duplicates, so it makes a final pass to reduce two types of duplicates - any later member with the first, or any two adjacent members. if (1 < ng) { gid_t first = *g; gid_t *next; gid_t *groups_end = g + ng; for (next = g + 1; next < groups_end; next++) { if (*next == first || *next == *g) ng--; else *++g = *next; } } Coverity was assuming that ng-- could be executed enough times to make it go negative, but looking closer at the loop bounds, the loop cannot run more than the original ng - 1 times, so ng >= 1. I'm not sure if upstream gnulib can or should do anything to silence Coverity from triggering the false positive. But the added assert in the caller definitely lets Coverity fill in the gaps for what we know to be true. -- Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org