From: Ignat Korchagin <ignat@xxxxxxxxxxxxxx>
[ Upstream commit 7e0f122c65912740327e4c54472acaa5f85868cb ]
Commit d0009effa886 ("netfilter: nf_tables: validate NFPROTO_* family") added
some validation of NFPROTO_* families in the nft_compat module, but it broke
the ability to use legacy iptables modules in dual-stack nftables.
While with legacy iptables one had to independently manage IPv4 and IPv6
tables, with nftables it is possible to have dual-stack tables sharing the
rules. Moreover, it was possible to use rules based on legacy iptables
match/target modules in dual-stack nftables.
As an example, the program from [2] creates an INET dual-stack family table
using an xt_bpf based rule, which looks like the following (the actual output
was generated with a patched nft tool as the current nft tool does not parse
dual stack tables with legacy match rules, so consider it for illustrative
purposes only):
table inet testfw {
chain input {
type filter hook prerouting priority filter; policy accept;
bytecode counter packets 0 bytes 0 accept
}
}
After d0009effa886 ("netfilter: nf_tables: validate NFPROTO_* family") we get
EOPNOTSUPP for the above program.
Fix this by allowing NFPROTO_INET for nft_(match/target)_validate(), but also
restrict the functions to classic iptables hooks.
Changes in v3:
* clarify that upstream nft will not display such configuration properly and
that the output was generated with a patched nft tool
* remove example program from commit description and link to it instead
* no code changes otherwise
Changes in v2:
* restrict nft_(match/target)_validate() to classic iptables hooks
* rewrite example program to use unmodified libnftnl
Fixes: d0009effa886 ("netfilter: nf_tables: validate NFPROTO_* family")
Link: https://lore.kernel.org/all/Zc1PfoWN38UuFJRI@calendula/T/#mc947262582c90fec044c7a3398cc92fac7afea72 [1]
Link: https://lore.kernel.org/all/20240220145509.53357-1-ignat@xxxxxxxxxxxxxx/ [2]
Reported-by: Jordan Griege <jgriege@xxxxxxxxxxxxxx>
Signed-off-by: Ignat Korchagin <ignat@xxxxxxxxxxxxxx>
Signed-off-by: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/netfilter/nft_compat.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)
--- a/net/netfilter/nft_compat.c
+++ b/net/netfilter/nft_compat.c
@@ -321,10 +321,20 @@ static int nft_target_validate(const str
if (ctx->family != NFPROTO_IPV4 &&
ctx->family != NFPROTO_IPV6 &&
+ ctx->family != NFPROTO_INET &&
ctx->family != NFPROTO_BRIDGE &&
ctx->family != NFPROTO_ARP)
return -EOPNOTSUPP;
+ ret = nft_chain_validate_hooks(ctx->chain,
+ (1 << NF_INET_PRE_ROUTING) |
+ (1 << NF_INET_LOCAL_IN) |
+ (1 << NF_INET_FORWARD) |
+ (1 << NF_INET_LOCAL_OUT) |
+ (1 << NF_INET_POST_ROUTING));
+ if (ret)
+ return ret;
+
if (nft_is_base_chain(ctx->chain)) {
const struct nft_base_chain *basechain =
nft_base_chain(ctx->chain);
@@ -568,10 +578,20 @@ static int nft_match_validate(const stru
if (ctx->family != NFPROTO_IPV4 &&
ctx->family != NFPROTO_IPV6 &&
+ ctx->family != NFPROTO_INET &&
ctx->family != NFPROTO_BRIDGE &&
ctx->family != NFPROTO_ARP)
return -EOPNOTSUPP;
+ ret = nft_chain_validate_hooks(ctx->chain,
+ (1 << NF_INET_PRE_ROUTING) |
+ (1 << NF_INET_LOCAL_IN) |
+ (1 << NF_INET_FORWARD) |
+ (1 << NF_INET_LOCAL_OUT) |
+ (1 << NF_INET_POST_ROUTING));
+ if (ret)
+ return ret;
+
if (nft_is_base_chain(ctx->chain)) {
const struct nft_base_chain *basechain =
nft_base_chain(ctx->chain);
Patches currently in stable-queue which might be from kroah.com@xxxxxxxxxxxxxxx are
queue-4.19/netfilter-nf_tables-bogus-ebusy-when-deleting-flowtable-after-flush-for-4.19.patch
queue-4.19/netfilter-nft_set_rbtree-switch-to-node-list-walk-for-overlap-detection.patch
queue-4.19/netfilter-nf_tables-validate-nfproto_-family.patch
queue-4.19/netfilter-nf_tables-unregister-flowtable-hooks-on-netns-exit.patch
queue-4.19/netfilter-nf_tables-fix-gc-transaction-races-with-netns-and-netlink-event-exit-path.patch
queue-4.19/netfilter-nft_set_rbtree-use-read-spinlock-to-avoid-datapath-contention.patch
queue-4.19/netfilter-nft_dynset-report-eopnotsupp-on-missing-set-feature.patch
queue-4.19/netfilter-nf_tables-discard-table-flag-update-with-pending-basechain-deletion.patch
queue-4.19/netfilter-nft_set_rbtree-skip-sync-gc-for-new-elements-in-this-transaction.patch
queue-4.19/netfilter-nf_tables-mark-set-as-dead-when-unbinding-anonymous-set-with-timeout.patch
queue-4.19/netfilter-nf_tables-reject-new-basechain-after-table-flag-update.patch
queue-4.19/netfilter-nf_tables-gc-transaction-race-with-netns-dismantle.patch
queue-4.19/netfilter-nftables-update-table-flags-from-the-commit-phase.patch
queue-4.19/netfilter-nf_tables-allow-nfproto_inet-in-nft_-match-target-_validate.patch
queue-4.19/netfilter-nft_set_rbtree-skip-end-interval-element-from-gc.patch
queue-4.19/netfilter-nf_tables-drop-map-element-references-from-preparation-phase.patch
queue-4.19/netfilter-nf_tables-gc-transaction-race-with-abort-path.patch
queue-4.19/netfilter-nf_tables-fix-memleak-when-more-than-255-elements-expired.patch
queue-4.19/netfilter-nft_set_rbtree-add-missing-expired-checks.patch
queue-4.19/netfilter-nf_tables-double-hook-unregistration-in-netns-path.patch
queue-4.19/netfilter-nft_dynset-relax-superfluous-check-on-set-updates.patch
queue-4.19/netfilter-nf_tables-defer-gc-run-if-previous-batch-is-still-pending.patch
queue-4.19/netfilter-nft_set_hash-try-later-when-gc-hits-eagain-on-iteration.patch
queue-4.19/netfilter-nft_dynset-fix-timeouts-later-than-23-days.patch
queue-4.19/netfilter-nf_tables-mark-newset-as-dead-on-transaction-abort.patch
queue-4.19/netfilter-nf_tables-don-t-skip-expired-elements-during-walk.patch
queue-4.19/netfilter-nftables-rename-set-element-data-activation-deactivation-functions.patch
queue-4.19/netfilter-nf_tables-gc-transaction-api-to-avoid-race-with-control-plane.patch
queue-4.19/netfilter-nf_tables-set-dormant-flag-on-hook-register-failure.patch
queue-4.19/netfilter-nf_tables-remove-busy-mark-and-gc-batch-api.patch
queue-4.19/netfilter-nf_tables-skip-dead-set-elements-in-netlink-dump.patch
queue-4.19/netfilter-nf_tables-adapt-set-backend-to-use-gc-transaction-api.patch
queue-4.19/netfilter-nft_set_rbtree-fix-overlap-expiration-walk.patch
queue-4.19/netfilter-nf_tables-fix-table-flag-updates.patch
queue-4.19/netfilter-nf_tables-do-not-compare-internal-table-flags-on-updates.patch
queue-4.19/netfilter-nft_set_rbtree-allow-loose-matching-of-closing-element-in-interval.patch
queue-4.19/netfilter-nftables-exthdr-fix-4-byte-stack-oob-write.patch
queue-4.19/netfilter-nft_set_rbtree-fix-null-deref-on-element-insertion.patch
queue-4.19/netfilter-nf_tables-pass-context-to-nft_set_destroy.patch
queue-4.19/netfilter-nf_tables-disable-toggling-dormant-table-state-more-than-once.patch
