2:24 a.m.
There's this problem on the recent gcc-6.1:
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++) {
^~~~~~~
GCC basically fails to see, that the
virDomainChrGetDomainPtrsInternal will never actually return NULL
because it's never called over a domain char device with _LAST
type. But to make it shut up, lets turn this function into
returning an integer and check in the callers if a zero value
value was returned.
Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com>
---
diff to v2:
- Yet another improvement as suggested in review of v2
src/conf/domain_conf.c | 39 +++++++++++++++++++++++----------------
1 file changed, 23 insertions(+), 16 deletions(-)
diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index 7d46d0b..9f9fdf2 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -14038,7 +14038,7 @@ virDomainChrFind(virDomainDefPtr def,
/* Return the address within vmdef to be modified when working with a
* chrdefptr of the given type. */
-static void
+static int ATTRIBUTE_RETURN_CHECK
virDomainChrGetDomainPtrsInternal(virDomainDefPtr vmdef,
virDomainChrDeviceType type,
virDomainChrDefPtr ***arrPtr,
@@ -14048,28 +14048,30 @@ virDomainChrGetDomainPtrsInternal(virDomainDefPtr vmdef,
case VIR_DOMAIN_CHR_DEVICE_TYPE_PARALLEL:
*arrPtr = &vmdef->parallels;
*cntPtr = &vmdef->nparallels;
- break;
+ return 0;
case VIR_DOMAIN_CHR_DEVICE_TYPE_SERIAL:
*arrPtr = &vmdef->serials;
*cntPtr = &vmdef->nserials;
- break;
+ return 0;
case VIR_DOMAIN_CHR_DEVICE_TYPE_CONSOLE:
*arrPtr = &vmdef->consoles;
*cntPtr = &vmdef->nconsoles;
- break;
+ return 0;
case VIR_DOMAIN_CHR_DEVICE_TYPE_CHANNEL:
*arrPtr = &vmdef->channels;
*cntPtr = &vmdef->nchannels;
- break;
+ return 0;
case VIR_DOMAIN_CHR_DEVICE_TYPE_LAST:
- *arrPtr = NULL;
- *cntPtr = NULL;
break;
}
+
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ _("Unknown char device type: %d"), type);
+ return -1;
}
@@ -14085,14 +14087,13 @@ virDomainChrGetDomainPtrs(const virDomainDef *vmdef,
size_t *cntVar = NULL;
/* Cast away const; we add it back in the final assignment. */
- virDomainChrGetDomainPtrsInternal((virDomainDefPtr) vmdef, type,
- &arrVar, &cntVar);
- if (arrVar) {
+ if (virDomainChrGetDomainPtrsInternal((virDomainDefPtr) vmdef, type,
+ &arrVar, &cntVar) < 0) {
+ *arrPtr = NULL;
+ *cntPtr = 0;
+ } else {
*arrPtr = (const virDomainChrDef **) *arrVar;
*cntPtr = *cntVar;
- } else {
- *arrPtr = NULL;
- *cntPtr = 0;
}
}
@@ -14104,7 +14105,9 @@ virDomainChrPreAlloc(virDomainDefPtr vmdef,
virDomainChrDefPtr **arrPtr = NULL;
size_t *cntPtr = NULL;
- virDomainChrGetDomainPtrsInternal(vmdef, chr->deviceType, &arrPtr,
&cntPtr);
+ if (virDomainChrGetDomainPtrsInternal(vmdef, chr->deviceType,
+ &arrPtr, &cntPtr) < 0)
+ return -1;
return VIR_REALLOC_N(*arrPtr, *cntPtr + 1);
}
@@ -14116,7 +14119,9 @@ virDomainChrInsertPreAlloced(virDomainDefPtr vmdef,
virDomainChrDefPtr **arrPtr = NULL;
size_t *cntPtr = NULL;
- virDomainChrGetDomainPtrsInternal(vmdef, chr->deviceType, &arrPtr,
&cntPtr);
+ if (virDomainChrGetDomainPtrsInternal(vmdef, chr->deviceType,
+ &arrPtr, &cntPtr) < 0)
+ return;
VIR_APPEND_ELEMENT_INPLACE(*arrPtr, *cntPtr, chr);
}
@@ -14128,7 +14133,9 @@ virDomainChrRemove(virDomainDefPtr vmdef,
virDomainChrDefPtr ret = NULL, **arrPtr = NULL;
size_t i, *cntPtr = NULL;
- virDomainChrGetDomainPtrsInternal(vmdef, chr->deviceType, &arrPtr,
&cntPtr);
+ if (virDomainChrGetDomainPtrsInternal(vmdef, chr->deviceType,
+ &arrPtr, &cntPtr) < 0)
+ return NULL;
for (i = 0; i < *cntPtr; i++) {
ret = (*arrPtr)[i];
--
2.8.3