[PATCH 1/2 nf] netfilter: nft_compat: fix hook validation for non-base chains

[Pablo Neira Ayuso]

Set hook_mask to zero for non-base chains, otherwise people may hit
bogus errors from the xt_check_target() and xt_check_match() when
validating the uninitialized hook_mask.

Signed-off-by: Pablo Neira Ayuso <***@netfilter.org>
---
net/netfilter/nft_compat.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/net/netfilter/nft_compat.c b/net/netfilter/nft_compat.c
index 7e2683c..44ae273 100644
--- a/net/netfilter/nft_compat.c
+++ b/net/netfilter/nft_compat.c
@@ -95,6 +95,8 @@ nft_target_set_tgchk_param(struct xt_tgchk_param *par,
const struct nf_hook_ops *ops = &basechain->ops[0];

par->hook_mask = 1 << ops->hooknum;
+ } else {
+ par->hook_mask = 0;
}
par->family = ctx->afi->family;
}
@@ -293,6 +295,8 @@ nft_match_set_mtchk_param(struct xt_mtchk_param *par, const struct nft_ctx *ctx,
const struct nf_hook_ops *ops = &basechain->ops[0];

par->hook_mask = 1 << ops->hooknum;
+ } else {
+ par->hook_mask = 0;
}
par->family = ctx->afi->family;
}