[NETFILTER]: xt_limit: add compat conversion functions (02c63cf7) · Commits · 戴 / test

net/netfilter/xt_limit.c

+49 −0

Original line number	Diff line number	Diff line
		@@ -135,6 +135,50 @@ ipt_limit_checkentry(const char *tablename,
		return 1;
		}

		#ifdef CONFIG_COMPAT
		struct compat_xt_rateinfo {
		u_int32_t avg;
		u_int32_t burst;

		compat_ulong_t prev;
		u_int32_t credit;
		u_int32_t credit_cap, cost;

		u_int32_t master;
		};

		/* To keep the full "prev" timestamp, the upper 32 bits are stored in the
		* master pointer, which does not need to be preserved. */
		static void compat_from_user(void dst, void src)
		{
		struct compat_xt_rateinfo *cm = src;
		struct xt_rateinfo m = {
		.avg = cm->avg,
		.burst = cm->burst,
		.prev = cm->prev \| (unsigned long)cm->master << 32,
		.credit = cm->credit,
		.credit_cap = cm->credit_cap,
		.cost = cm->cost,
		};
		memcpy(dst, &m, sizeof(m));
		}

		static int compat_to_user(void __user dst, void src)
		{
		struct xt_rateinfo *m = src;
		struct compat_xt_rateinfo cm = {
		.avg = m->avg,
		.burst = m->burst,
		.prev = m->prev,
		.credit = m->credit,
		.credit_cap = m->credit_cap,
		.cost = m->cost,
		.master = m->prev >> 32,
		};
		return copy_to_user(dst, &cm, sizeof(cm)) ? -EFAULT : 0;
		}
		#endif /* CONFIG_COMPAT */

		static struct xt_match xt_limit_match[] = {
		{
		.name = "limit",
		@@ -142,6 +186,11 @@ static struct xt_match xt_limit_match[] = {
		.checkentry = ipt_limit_checkentry,
		.match = ipt_limit_match,
		.matchsize = sizeof(struct xt_rateinfo),
		#ifdef CONFIG_COMPAT
		.compatsize = sizeof(struct compat_xt_rateinfo),
		.compat_from_user = compat_from_user,
		.compat_to_user = compat_to_user,
		#endif
		.me = THIS_MODULE,
		},
		{