net: convert fib_rule.refcnt from atomic_t to refcount_t
refcount_t type and corresponding API should be
used instead of atomic_t when the variable is used as
a reference counter. This allows to avoid accidental
refcounter overflows that might lead to use-after-free
situations.
Signed-off-by: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: David Windsor <dwindsor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c
index 3bba291..c4ecd9f 100644
--- a/net/core/fib_rules.c
+++ b/net/core/fib_rules.c
@@ -46,7 +46,7 @@ int fib_default_rule_add(struct fib_rules_ops *ops,
if (r == NULL)
return -ENOMEM;
- atomic_set(&r->refcnt, 1);
+ refcount_set(&r->refcnt, 1);
r->action = FR_ACT_TO_TBL;
r->pref = pref;
r->table = table;
@@ -283,7 +283,7 @@ int fib_rules_lookup(struct fib_rules_ops *ops, struct flowi *fl,
if (err != -EAGAIN) {
if ((arg->flags & FIB_LOOKUP_NOREF) ||
- likely(atomic_inc_not_zero(&rule->refcnt))) {
+ likely(refcount_inc_not_zero(&rule->refcnt))) {
arg->rule = rule;
goto out;
}