5.15-stable review patch. If anyone has any objections, please let me know.
------------------
From: Jeremy Sowden jeremy@azazel.net
[ Upstream commit 6f56ad1b92328997e1b1792047099df6f8d7acb5 ]
`nf_nat_redirect_ipv4` takes a `struct nf_nat_ipv4_multi_range_compat`, but converts it internally to a `struct nf_nat_range2`. Change the function to take the latter, factor out the code now shared with `nf_nat_redirect_ipv6`, move the conversion to the xt_REDIRECT module, and update the ipv4 range initialization in the nft_redir module.
Replace a bare hex constant for 127.0.0.1 with a macro.
Remove `WARN_ON`. `nf_nat_setup_info` calls `nf_ct_is_confirmed`:
/* Can't setup nat info for confirmed ct. */ if (nf_ct_is_confirmed(ct)) return NF_ACCEPT;
This means that `ct` cannot be null or the kernel will crash, and implies that `ctinfo` is `IP_CT_NEW` or `IP_CT_RELATED`.
nft_redir has separate ipv4 and ipv6 call-backs which share much of their code, and an inet one switch containing a switch that calls one of the others based on the family of the packet. Merge the ipv4 and ipv6 ones into the inet one in order to get rid of the duplicate code.
Const-qualify the `priv` pointer since we don't need to write through it.
Assign `priv->flags` to the range instead of OR-ing it in.
Set the `NF_NAT_RANGE_PROTO_SPECIFIED` flag once during init, rather than on every eval.
Signed-off-by: Jeremy Sowden jeremy@azazel.net Signed-off-by: Florian Westphal fw@strlen.de Stable-dep-of: 80abbe8a8263 ("netfilter: nat: fix ipv6 nat redirect with mapped and scoped addresses") Signed-off-by: Sasha Levin sashal@kernel.org --- include/net/netfilter/nf_nat_redirect.h | 3 +- net/netfilter/nf_nat_redirect.c | 71 ++++++++++----------- net/netfilter/nft_redir.c | 84 +++++++++---------------- net/netfilter/xt_REDIRECT.c | 10 ++- 4 files changed, 72 insertions(+), 96 deletions(-)
diff --git a/include/net/netfilter/nf_nat_redirect.h b/include/net/netfilter/nf_nat_redirect.h index 2418653a66db1..279380de904c8 100644 --- a/include/net/netfilter/nf_nat_redirect.h +++ b/include/net/netfilter/nf_nat_redirect.h @@ -6,8 +6,7 @@ #include <uapi/linux/netfilter/nf_nat.h>
unsigned int -nf_nat_redirect_ipv4(struct sk_buff *skb, - const struct nf_nat_ipv4_multi_range_compat *mr, +nf_nat_redirect_ipv4(struct sk_buff *skb, const struct nf_nat_range2 *range, unsigned int hooknum); unsigned int nf_nat_redirect_ipv6(struct sk_buff *skb, const struct nf_nat_range2 *range, diff --git a/net/netfilter/nf_nat_redirect.c b/net/netfilter/nf_nat_redirect.c index f91579c821e9a..6616ba5d0b049 100644 --- a/net/netfilter/nf_nat_redirect.c +++ b/net/netfilter/nf_nat_redirect.c @@ -10,6 +10,7 @@
#include <linux/if.h> #include <linux/inetdevice.h> +#include <linux/in.h> #include <linux/ip.h> #include <linux/kernel.h> #include <linux/netdevice.h> @@ -24,54 +25,56 @@ #include <net/netfilter/nf_nat.h> #include <net/netfilter/nf_nat_redirect.h>
+static unsigned int +nf_nat_redirect(struct sk_buff *skb, const struct nf_nat_range2 *range, + const union nf_inet_addr *newdst) +{ + struct nf_nat_range2 newrange; + enum ip_conntrack_info ctinfo; + struct nf_conn *ct; + + ct = nf_ct_get(skb, &ctinfo); + + memset(&newrange, 0, sizeof(newrange)); + + newrange.flags = range->flags | NF_NAT_RANGE_MAP_IPS; + newrange.min_addr = *newdst; + newrange.max_addr = *newdst; + newrange.min_proto = range->min_proto; + newrange.max_proto = range->max_proto; + + return nf_nat_setup_info(ct, &newrange, NF_NAT_MANIP_DST); +} + unsigned int -nf_nat_redirect_ipv4(struct sk_buff *skb, - const struct nf_nat_ipv4_multi_range_compat *mr, +nf_nat_redirect_ipv4(struct sk_buff *skb, const struct nf_nat_range2 *range, unsigned int hooknum) { - struct nf_conn *ct; - enum ip_conntrack_info ctinfo; - __be32 newdst; - struct nf_nat_range2 newrange; + union nf_inet_addr newdst = {};
WARN_ON(hooknum != NF_INET_PRE_ROUTING && hooknum != NF_INET_LOCAL_OUT);
- ct = nf_ct_get(skb, &ctinfo); - WARN_ON(!(ct && (ctinfo == IP_CT_NEW || ctinfo == IP_CT_RELATED))); - /* Local packets: make them go to loopback */ if (hooknum == NF_INET_LOCAL_OUT) { - newdst = htonl(0x7F000001); + newdst.ip = htonl(INADDR_LOOPBACK); } else { const struct in_device *indev;
- newdst = 0; - indev = __in_dev_get_rcu(skb->dev); if (indev) { const struct in_ifaddr *ifa;
ifa = rcu_dereference(indev->ifa_list); if (ifa) - newdst = ifa->ifa_local; + newdst.ip = ifa->ifa_local; }
- if (!newdst) + if (!newdst.ip) return NF_DROP; }
- /* Transfer from original range. */ - memset(&newrange.min_addr, 0, sizeof(newrange.min_addr)); - memset(&newrange.max_addr, 0, sizeof(newrange.max_addr)); - newrange.flags = mr->range[0].flags | NF_NAT_RANGE_MAP_IPS; - newrange.min_addr.ip = newdst; - newrange.max_addr.ip = newdst; - newrange.min_proto = mr->range[0].min; - newrange.max_proto = mr->range[0].max; - - /* Hand modified range to generic setup. */ - return nf_nat_setup_info(ct, &newrange, NF_NAT_MANIP_DST); + return nf_nat_redirect(skb, range, &newdst); } EXPORT_SYMBOL_GPL(nf_nat_redirect_ipv4);
@@ -81,14 +84,10 @@ unsigned int nf_nat_redirect_ipv6(struct sk_buff *skb, const struct nf_nat_range2 *range, unsigned int hooknum) { - struct nf_nat_range2 newrange; - struct in6_addr newdst; - enum ip_conntrack_info ctinfo; - struct nf_conn *ct; + union nf_inet_addr newdst = {};
- ct = nf_ct_get(skb, &ctinfo); if (hooknum == NF_INET_LOCAL_OUT) { - newdst = loopback_addr; + newdst.in6 = loopback_addr; } else { struct inet6_dev *idev; struct inet6_ifaddr *ifa; @@ -98,7 +97,7 @@ nf_nat_redirect_ipv6(struct sk_buff *skb, const struct nf_nat_range2 *range, if (idev != NULL) { read_lock_bh(&idev->lock); list_for_each_entry(ifa, &idev->addr_list, if_list) { - newdst = ifa->addr; + newdst.in6 = ifa->addr; addr = true; break; } @@ -109,12 +108,6 @@ nf_nat_redirect_ipv6(struct sk_buff *skb, const struct nf_nat_range2 *range, return NF_DROP; }
- newrange.flags = range->flags | NF_NAT_RANGE_MAP_IPS; - newrange.min_addr.in6 = newdst; - newrange.max_addr.in6 = newdst; - newrange.min_proto = range->min_proto; - newrange.max_proto = range->max_proto; - - return nf_nat_setup_info(ct, &newrange, NF_NAT_MANIP_DST); + return nf_nat_redirect(skb, range, &newdst); } EXPORT_SYMBOL_GPL(nf_nat_redirect_ipv6); diff --git a/net/netfilter/nft_redir.c b/net/netfilter/nft_redir.c index e64f531d66cfc..677ce42183691 100644 --- a/net/netfilter/nft_redir.c +++ b/net/netfilter/nft_redir.c @@ -64,6 +64,8 @@ static int nft_redir_init(const struct nft_ctx *ctx, } else { priv->sreg_proto_max = priv->sreg_proto_min; } + + priv->flags |= NF_NAT_RANGE_PROTO_SPECIFIED; }
if (tb[NFTA_REDIR_FLAGS]) { @@ -98,25 +100,37 @@ static int nft_redir_dump(struct sk_buff *skb, const struct nft_expr *expr) return -1; }
-static void nft_redir_ipv4_eval(const struct nft_expr *expr, - struct nft_regs *regs, - const struct nft_pktinfo *pkt) +static void nft_redir_eval(const struct nft_expr *expr, + struct nft_regs *regs, + const struct nft_pktinfo *pkt) { - struct nft_redir *priv = nft_expr_priv(expr); - struct nf_nat_ipv4_multi_range_compat mr; + const struct nft_redir *priv = nft_expr_priv(expr); + struct nf_nat_range2 range;
- memset(&mr, 0, sizeof(mr)); + memset(&range, 0, sizeof(range)); + range.flags = priv->flags; if (priv->sreg_proto_min) { - mr.range[0].min.all = (__force __be16)nft_reg_load16( - ®s->data[priv->sreg_proto_min]); - mr.range[0].max.all = (__force __be16)nft_reg_load16( - ®s->data[priv->sreg_proto_max]); - mr.range[0].flags |= NF_NAT_RANGE_PROTO_SPECIFIED; + range.min_proto.all = (__force __be16) + nft_reg_load16(®s->data[priv->sreg_proto_min]); + range.max_proto.all = (__force __be16) + nft_reg_load16(®s->data[priv->sreg_proto_max]); }
- mr.range[0].flags |= priv->flags; - - regs->verdict.code = nf_nat_redirect_ipv4(pkt->skb, &mr, nft_hook(pkt)); + switch (nft_pf(pkt)) { + case NFPROTO_IPV4: + regs->verdict.code = nf_nat_redirect_ipv4(pkt->skb, &range, + nft_hook(pkt)); + break; +#ifdef CONFIG_NF_TABLES_IPV6 + case NFPROTO_IPV6: + regs->verdict.code = nf_nat_redirect_ipv6(pkt->skb, &range, + nft_hook(pkt)); + break; +#endif + default: + WARN_ON_ONCE(1); + break; + } }
static void @@ -129,7 +143,7 @@ static struct nft_expr_type nft_redir_ipv4_type; static const struct nft_expr_ops nft_redir_ipv4_ops = { .type = &nft_redir_ipv4_type, .size = NFT_EXPR_SIZE(sizeof(struct nft_redir)), - .eval = nft_redir_ipv4_eval, + .eval = nft_redir_eval, .init = nft_redir_init, .destroy = nft_redir_ipv4_destroy, .dump = nft_redir_dump, @@ -146,28 +160,6 @@ static struct nft_expr_type nft_redir_ipv4_type __read_mostly = { };
#ifdef CONFIG_NF_TABLES_IPV6 -static void nft_redir_ipv6_eval(const struct nft_expr *expr, - struct nft_regs *regs, - const struct nft_pktinfo *pkt) -{ - struct nft_redir *priv = nft_expr_priv(expr); - struct nf_nat_range2 range; - - memset(&range, 0, sizeof(range)); - if (priv->sreg_proto_min) { - range.min_proto.all = (__force __be16)nft_reg_load16( - ®s->data[priv->sreg_proto_min]); - range.max_proto.all = (__force __be16)nft_reg_load16( - ®s->data[priv->sreg_proto_max]); - range.flags |= NF_NAT_RANGE_PROTO_SPECIFIED; - } - - range.flags |= priv->flags; - - regs->verdict.code = - nf_nat_redirect_ipv6(pkt->skb, &range, nft_hook(pkt)); -} - static void nft_redir_ipv6_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr) { @@ -178,7 +170,7 @@ static struct nft_expr_type nft_redir_ipv6_type; static const struct nft_expr_ops nft_redir_ipv6_ops = { .type = &nft_redir_ipv6_type, .size = NFT_EXPR_SIZE(sizeof(struct nft_redir)), - .eval = nft_redir_ipv6_eval, + .eval = nft_redir_eval, .init = nft_redir_init, .destroy = nft_redir_ipv6_destroy, .dump = nft_redir_dump, @@ -196,20 +188,6 @@ static struct nft_expr_type nft_redir_ipv6_type __read_mostly = { #endif
#ifdef CONFIG_NF_TABLES_INET -static void nft_redir_inet_eval(const struct nft_expr *expr, - struct nft_regs *regs, - const struct nft_pktinfo *pkt) -{ - switch (nft_pf(pkt)) { - case NFPROTO_IPV4: - return nft_redir_ipv4_eval(expr, regs, pkt); - case NFPROTO_IPV6: - return nft_redir_ipv6_eval(expr, regs, pkt); - } - - WARN_ON_ONCE(1); -} - static void nft_redir_inet_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr) { @@ -220,7 +198,7 @@ static struct nft_expr_type nft_redir_inet_type; static const struct nft_expr_ops nft_redir_inet_ops = { .type = &nft_redir_inet_type, .size = NFT_EXPR_SIZE(sizeof(struct nft_redir)), - .eval = nft_redir_inet_eval, + .eval = nft_redir_eval, .init = nft_redir_init, .destroy = nft_redir_inet_destroy, .dump = nft_redir_dump, diff --git a/net/netfilter/xt_REDIRECT.c b/net/netfilter/xt_REDIRECT.c index 353ca7801251a..ff66b56a3f97d 100644 --- a/net/netfilter/xt_REDIRECT.c +++ b/net/netfilter/xt_REDIRECT.c @@ -46,7 +46,6 @@ static void redirect_tg_destroy(const struct xt_tgdtor_param *par) nf_ct_netns_put(par->net, par->family); }
-/* FIXME: Take multiple ranges --RR */ static int redirect_tg4_check(const struct xt_tgchk_param *par) { const struct nf_nat_ipv4_multi_range_compat *mr = par->targinfo; @@ -65,7 +64,14 @@ static int redirect_tg4_check(const struct xt_tgchk_param *par) static unsigned int redirect_tg4(struct sk_buff *skb, const struct xt_action_param *par) { - return nf_nat_redirect_ipv4(skb, par->targinfo, xt_hooknum(par)); + const struct nf_nat_ipv4_multi_range_compat *mr = par->targinfo; + struct nf_nat_range2 range = { + .flags = mr->range[0].flags, + .min_proto = mr->range[0].min, + .max_proto = mr->range[0].max, + }; + + return nf_nat_redirect_ipv4(skb, &range, xt_hooknum(par)); }
static struct xt_target redirect_tg_reg[] __read_mostly = {