Re: [libvirt] [PATCH 6/6] domain_conf: Avoid false positive

On Tue, May 31, 2016 at 12:33:33 +0200, Michal Privoznik wrote: > Gcc fails to see that virDomainChrGetDomainPtrsInternal always > sets pointers to a non NULL value (except for > chr device type VIR_DOMAIN_CHR_DEVICE_TYPE_LAST which if occurs, > we are in way bigger problem than NULL deref). > > In file included from conf/domain_conf.c:37:0: > conf/domain_conf.c: In function 'virDomainChrPreAlloc': > conf/domain_conf.c:14109:35: error: potential null pointer dereference [-Werror=null-dereference] > return VIR_REALLOC_N(*arrPtr, *cntPtr + 1); > ^~ > ./util/viralloc.h:158:73: note: in definition of macro 'VIR_REALLOC_N' > # define VIR_REALLOC_N(ptr, count) virReallocN(&(ptr), sizeof(*(ptr)), (count), \ > ^~~~~ > conf/domain_conf.c: In function 'virDomainChrRemove': > conf/domain_conf.c:14133:21: error: potential null pointer dereference [-Werror=null-dereference] > for (i = 0; i < *cntPtr; i++) { > ^~~~~~~ > cc1: all warnings being treated as errors > > Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com&gt; > --- > src/conf/domain_conf.c | 18 ++++++++++++++++++ > 1 file changed, 18 insertions(+) > > diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c > index 3daeb1e..67ed4d7 100644 > --- a/src/conf/domain_conf.c > +++ b/src/conf/domain_conf.c > @@ -14106,6 +14106,12 @@ virDomainChrPreAlloc(virDomainDefPtr vmdef, > > virDomainChrGetDomainPtrsInternal(vmdef, chr->deviceType, &arrPtr, &cntPtr); > > + if (!arrPtr || !cntPtr) { > + virReportError(VIR_ERR_INTERNAL_ERROR, "%s", > + _("Impossible happened")); > + return -1; > + } > + > return VIR_REALLOC_N(*arrPtr, *cntPtr + 1); > } NACK