Object property insertion code iterates over an integer to get an unused index that can be used as an unique name for an object property. This loop increments the integer value indefinitely. Although very unlikely, this can still cause an integer overflow. In this change, we fix the above code by checking against INT16_MAX and making sure that the interger index does not overflow beyond that value. If no available index is found, the code would cause an assertion failure. This assertion failure is necessary because the callers of the function do not check the return value for NULL.
Signed-off-by: Ani Sinha <a...@anisinha.ca> Reviewed-by: Daniel P. Berrangé <berra...@redhat.com> --- qom/object.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) changelog: v1: initial version v2: change INT_MAX to INT16_MAX in code v3: make the same change in commit log. Sorry for missing it. diff --git a/qom/object.c b/qom/object.c index 387efb25eb..9962874598 100644 --- a/qom/object.c +++ b/qom/object.c @@ -1166,11 +1166,11 @@ object_property_try_add(Object *obj, const char *name, const char *type, if (name_len >= 3 && !memcmp(name + name_len - 3, "[*]", 4)) { int i; - ObjectProperty *ret; + ObjectProperty *ret = NULL; char *name_no_array = g_strdup(name); name_no_array[name_len - 3] = '\0'; - for (i = 0; ; ++i) { + for (i = 0; i < INT16_MAX; ++i) { char *full_name = g_strdup_printf("%s[%d]", name_no_array, i); ret = object_property_try_add(obj, full_name, type, get, set, @@ -1181,6 +1181,7 @@ object_property_try_add(Object *obj, const char *name, const char *type, } } g_free(name_no_array); + assert(ret); return ret; } -- 2.17.1