From 435bf0d3f99a164df7e8c30428cef266b91d1d3b Mon Sep 17 00:00:00 2001 From: John Fastabend Date: Wed, 18 Oct 2017 07:10:15 -0700 Subject: [PATCH] bpf: enforce TCP only support for sockmap Only TCP sockets have been tested and at the moment the state change callback only handles TCP sockets. This adds a check to ensure that sockets actually being added are TCP sockets. For net-next we can consider UDP support. Signed-off-by: John Fastabend Acked-by: Daniel Borkmann Acked-by: Alexei Starovoitov Signed-off-by: David S. Miller --- kernel/bpf/sockmap.c | 6 ++++++ tools/testing/selftests/bpf/test_maps.c | 12 +++++++++++- 2 files changed, 17 insertions(+), 1 deletion(-) diff --git a/kernel/bpf/sockmap.c b/kernel/bpf/sockmap.c index 6424ce0e4969..c68899d5b246 100644 --- a/kernel/bpf/sockmap.c +++ b/kernel/bpf/sockmap.c @@ -840,6 +840,12 @@ static int sock_map_update_elem(struct bpf_map *map, return -EINVAL; } + if (skops.sk->sk_type != SOCK_STREAM || + skops.sk->sk_protocol != IPPROTO_TCP) { + fput(socket->file); + return -EOPNOTSUPP; + } + err = sock_map_ctx_update_elem(&skops, map, key, flags); fput(socket->file); return err; diff --git a/tools/testing/selftests/bpf/test_maps.c b/tools/testing/selftests/bpf/test_maps.c index fe3a443a1102..50ce52d2013d 100644 --- a/tools/testing/selftests/bpf/test_maps.c +++ b/tools/testing/selftests/bpf/test_maps.c @@ -466,7 +466,7 @@ static void test_sockmap(int tasks, void *data) int one = 1, map_fd_rx, map_fd_tx, map_fd_break, s, sc, rc; struct bpf_map *bpf_map_rx, *bpf_map_tx, *bpf_map_break; int ports[] = {50200, 50201, 50202, 50204}; - int err, i, fd, sfd[6] = {0xdeadbeef}; + int err, i, fd, udp, sfd[6] = {0xdeadbeef}; u8 buf[20] = {0x0, 0x5, 0x3, 0x2, 0x1, 0x0}; int parse_prog, verdict_prog; struct sockaddr_in addr; @@ -548,6 +548,16 @@ static void test_sockmap(int tasks, void *data) goto out_sockmap; } + /* Test update with unsupported UDP socket */ + udp = socket(AF_INET, SOCK_DGRAM, 0); + i = 0; + err = bpf_map_update_elem(fd, &i, &udp, BPF_ANY); + if (!err) { + printf("Failed socket SOCK_DGRAM allowed '%i:%i'\n", + i, udp); + goto out_sockmap; + } + /* Test update without programs */ for (i = 0; i < 6; i++) { err = bpf_map_update_elem(fd, &i, &sfd[i], BPF_ANY); -- 2.20.1