[libvirt] [PATCH] nwfilter: Fix possible segfault on sometimes consumed variable
The virNWFilterIPAddrMapAddIPAddr code can consume the @addr parameter
on success when the @ifname is found in the ipAddressMap->hashTable
hash table in the call to virNWFilterVarValueAddValue; however, if
not found in the hash table, then @addr is formatted into a @val
which is stored in the table and on return the caller would be
expected to free @addr.
Thus, the caller has no way to determine on success whether @addr was
consumed, so in order to fix this create a @tmp variable which will
be stored/consumed when virNWFilterVarValueAddValue succeeds. That way
the caller can free @addr whether the function returns success or failure.
Signed-off-by: John Ferlan <jferlan(a)redhat.com>
---
src/conf/nwfilter_ipaddrmap.c | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/src/conf/nwfilter_ipaddrmap.c b/src/conf/nwfilter_ipaddrmap.c
index 9c8584ce2..5668f366d 100644
--- a/src/conf/nwfilter_ipaddrmap.c
+++ b/src/conf/nwfilter_ipaddrmap.c
@@ -26,7 +26,9 @@
#include "internal.h"
+#include "viralloc.h"
#include "virerror.h"
+#include "virstring.h"
#include "datatypes.h"
#include "nwfilter_params.h"
#include "nwfilter_ipaddrmap.h"
@@ -52,6 +54,7 @@ virNWFilterIPAddrMapAddIPAddr(const char *ifname, char *addr)
{
int ret = -1;
virNWFilterVarValuePtr val;
+ char *tmp = NULL;
virMutexLock(&ipAddressMapLock);
@@ -65,14 +68,18 @@ virNWFilterIPAddrMapAddIPAddr(const char *ifname, char *addr)
virNWFilterVarValueFree(val);
goto cleanup;
} else {
- if (virNWFilterVarValueAddValue(val, addr) < 0)
+ if (VIR_STRDUP(tmp, addr) < 0)
goto cleanup;
+ if (virNWFilterVarValueAddValue(val, tmp) < 0)
+ goto cleanup;
+ tmp = NULL;
}
ret = 0;
cleanup:
virMutexUnlock(&ipAddressMapLock);
+ VIR_FREE(tmp);
return ret;
}
--
2.13.5