segtree: fix string data initialisation

commit 63e3d5953c144abbc4ead2665ad7cec799c4cb64 upstream.

This uses the wrong length.  This must re-use the length of the datatype,
not the string length.

The added test cases will fail without the fix due to erroneous
overlap detection, which in itself is due to incorrect sorting of
the elements.

Example error:
 netlink: Error: interval overlaps with an existing one
 add element inet testifsets simple_wild {  "2-1" } failed.
 table inet testifsets {
      ...       elements = { "1-1", "abcdef*", "othername", "ppp0" }

... but clearly "2-1" doesn't overlap with any existing members.
The false detection is because of the "acvdef*" wildcard getting sorted
at the beginning of the list which is because its erronously initialised
as a 64bit number instead of 128 bits (16 bytes / IFNAMSIZ).

Fixes: 5e393ea1fc0a ("segtree: add string "range" reversal support")
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Pablo Neira Ayuso <pablo@netfilter.org>

2 files changed, 63 insertions, 1 deletions

diff --git a/src/segtree.c b/src/segtree.c
index b8fa9389..fcc1255b 100644
--- a/src/segtree.c
+++ b/src/segtree.c
@@ -472,7 +472,7 @@ static struct expr *interval_to_string(struct expr *low, struct expr *i, const m
 
 	expr = constant_expr_alloc(&low->location, low->dtype,
 				   BYTEORDER_HOST_ENDIAN,
-				   (str_len + 1) * BITS_PER_BYTE, data);
+				   len * BITS_PER_BYTE, data);
 
 	return __expr_to_set_elem(low, expr);
 }
diff --git a/tests/shell/testcases/sets/sets_with_ifnames b/tests/shell/testcases/sets/sets_with_ifnames
index 9531c856..713778b8 100755
--- a/tests/shell/testcases/sets/sets_with_ifnames
+++ b/tests/shell/testcases/sets/sets_with_ifnames
@@ -103,10 +103,67 @@ check_matching_icmp_ppp()
 	fi
 }
 
+check_add_del_ifnames()
+{
+	local what="$1"
+	local setname="$2"
+	local prefix="$3"
+	local data="$4"
+	local i=0
+
+	for i in $(seq 1 5);do
+		local cmd="element inet testifsets $setname { "
+		local to_batch=16
+
+		for j in $(seq 1 $to_batch);do
+			local name=$(printf '"%x-%d"' $i $j)
+
+			[ -n "$prefix" ] && cmd="$cmd $prefix . "
+
+			cmd="$cmd $name"
+
+			[ -n "$data" ] && cmd="$cmd : $data"
+
+			if [ $j -lt $to_batch ] ; then
+				cmd="$cmd, "
+			fi
+		done
+
+		cmd="$cmd }"
+
+		if ! $NFT "$what" "$cmd"; then
+			echo "$what $cmd failed."
+			$NFT list set inet testifsets $setname
+			exit 1
+		fi
+
+		if ! ip netns exec "$ns1" $NFT "$what" "$cmd"; then
+			echo "$ns1 $what $cmd failed."
+			ip netns exec "$ns1" $NFT list set inet testifsets $setname
+			exit 1
+		fi
+	done
+}
+
+check_add_ifnames()
+{
+	check_add_del_ifnames "add" "$1" "$2" "$3"
+}
+
+check_del_ifnames()
+{
+	check_add_del_ifnames "delete" "$1" "$2" "$3"
+}
+
 ip netns add "$ns1" || exit 111
 ip netns add "$ns2" || exit 111
 ip netns exec "$ns1" $NFT -f "$dumpfile" || exit 3
 
+check_add_ifnames "simple" "" ""
+check_add_ifnames "simple_wild" "" ""
+check_add_ifnames "concat" "10.1.2.2" ""
+check_add_ifnames "map_wild" "" "drop"
+
 for n in abcdef0 abcdef1 othername;do
 	check_elem simple $n
 done
@@ -148,3 +205,8 @@ ip -net "$ns2" addr add 10.1.2.2/24 dev veth0
 ip -net "$ns2" addr add 10.2.2.2/24 dev veth1
 
 check_matching_icmp_ppp
+
+check_del_ifnames "simple" "" ""
+check_del_ifnames "simple_wild" "" ""
+check_del_ifnames "concat" "10.1.2.2" ""
+check_del_ifnames "map_wild" "" "drop"