When a userspace conntrack helper with multiple expectation classes is updated via nfnetlink, every class ends up with the first class's max_expected and timeout values. nfnl_cthelper_update_policy_all() validates each new policy into the corresponding slot of the temporary new_policy array, but the second loop that commits the values into the live helper dereferences new_policy as a pointer instead of indexing it, so every iteration reads new_policy[0] regardless of i. An update that changes per-class values is silently collapsed onto class 0's values with no error returned to userspace. Index the temporary array by i in the commit loop so each class gets its own validated values. Fixes: 2c422257550f ("netfilter: nfnl_cthelper: fix runtime expectation policy updates") Cc: stable@vger.kernel.org Signed-off-by: David Carlier --- net/netfilter/nfnetlink_cthelper.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/netfilter/nfnetlink_cthelper.c b/net/netfilter/nfnetlink_cthelper.c index 0d16ad82d70c..34af6840803e 100644 --- a/net/netfilter/nfnetlink_cthelper.c +++ b/net/netfilter/nfnetlink_cthelper.c @@ -346,8 +346,8 @@ static int nfnl_cthelper_update_policy_all(struct nlattr *tb[], for (i = 0; i < helper->expect_class_max + 1; i++) { policy = (struct nf_conntrack_expect_policy *) &helper->expect_policy[i]; - policy->max_expected = new_policy->max_expected; - policy->timeout = new_policy->timeout; + policy->max_expected = new_policy[i].max_expected; + policy->timeout = new_policy[i].timeout; } err: -- 2.53.0