Zero-initialize the tc_gate dump struct to avoid leaking padding bytes
to userspace. Without clearing the struct, uninitialized stack padding
can be copied into the netlink reply during action dumps.
Fixes: a51c328df310 ("net: qos: introduce a gate control flow action")
Cc: stable@vger.kernel.org
Signed-off-by: Paul Moses <p@1g4.org>
---
net/sched/act_gate.c | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/net/sched/act_gate.c b/net/sched/act_gate.c
index 3ee07c3deaf97..ff963c165de90 100644
--- a/net/sched/act_gate.c
+++ b/net/sched/act_gate.c
@@ -656,17 +656,16 @@ static int tcf_gate_dump(struct sk_buff *skb, struct tc_action *a,
{
unsigned char *b = skb_tail_pointer(skb);
struct tcf_gate *gact = to_gate(a);
- struct tc_gate opt = {
- .index = gact->tcf_index,
- .refcnt = refcount_read(&gact->tcf_refcnt) - ref,
- .bindcnt = atomic_read(&gact->tcf_bindcnt) - bind,
- };
+ struct tc_gate opt = { };
struct tcfg_gate_entry *entry;
struct tcf_gate_params *p;
struct nlattr *entry_list;
struct tcf_t t;
spin_lock_bh(&gact->tcf_lock);
+ opt.index = gact->tcf_index;
+ opt.refcnt = refcount_read(&gact->tcf_refcnt) - ref;
+ opt.bindcnt = atomic_read(&gact->tcf_bindcnt) - bind;
opt.action = gact->tcf_action;
p = rcu_dereference_protected(gact->param,
--
2.52.GIT