netfilter: nft_range: add the missing NULL pointer check

Otherwise, kernel panic will happen if the user does not specify
the related attributes.

Fixes: 0f3cd9b36977 ("netfilter: nf_tables: add range expression")
Signed-off-by: Liping Zhang <zlpnobody@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/net/netfilter/nft_range.c b/net/netfilter/nft_range.c
index fbc88009ca2e..8f0aaaea1376 100644
--- a/net/netfilter/nft_range.c
+++ b/net/netfilter/nft_range.c
@@ -59,6 +59,12 @@ static int nft_range_init(const struct nft_ctx *ctx, const struct nft_expr *expr
         int err;
         u32 op;
 
+        if (!tb[NFTA_RANGE_SREG]      ||
+            !tb[NFTA_RANGE_OP]        ||
+            !tb[NFTA_RANGE_FROM_DATA] ||
+            !tb[NFTA_RANGE_TO_DATA])
+                return -EINVAL;
+
         err = nft_data_init(NULL, &priv->data_from, sizeof(priv->data_from),
                             &desc_from, tb[NFTA_RANGE_FROM_DATA]);
         if (err < 0)