From: Stanislav Fomichev <sdf@xxxxxxxxxx> [ Upstream commit 833d67ecdc5f35f1ebf59d0fccc1ce771434be9c ] Make sure we get optlen exported instead of getting EFAULT. Signed-off-by: Stanislav Fomichev <sdf@xxxxxxxxxx> Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx> Link: https://lore.kernel.org/bpf/20230418225343.553806-3-sdf@xxxxxxxxxx Stable-dep-of: 69844e335d8c ("selftests/bpf: Fix sockopt_sk selftest") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- .../selftests/bpf/prog_tests/sockopt_sk.c | 28 +++++++++++++++++++ .../testing/selftests/bpf/progs/sockopt_sk.c | 12 ++++++++ 2 files changed, 40 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/sockopt_sk.c b/tools/testing/selftests/bpf/prog_tests/sockopt_sk.c index 60d952719d275..4512dd808c335 100644 --- a/tools/testing/selftests/bpf/prog_tests/sockopt_sk.c +++ b/tools/testing/selftests/bpf/prog_tests/sockopt_sk.c @@ -3,6 +3,7 @@ #include "cgroup_helpers.h" #include <linux/tcp.h> +#include <linux/netlink.h> #include "sockopt_sk.skel.h" #ifndef SOL_TCP @@ -183,6 +184,33 @@ static int getsetsockopt(void) goto err; } + /* optval=NULL case is handled correctly */ + + close(fd); + fd = socket(AF_NETLINK, SOCK_RAW, 0); + if (fd < 0) { + log_err("Failed to create AF_NETLINK socket"); + return -1; + } + + buf.u32 = 1; + optlen = sizeof(__u32); + err = setsockopt(fd, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &buf, optlen); + if (err) { + log_err("Unexpected getsockopt(NETLINK_ADD_MEMBERSHIP) err=%d errno=%d", + err, errno); + goto err; + } + + optlen = 0; + err = getsockopt(fd, SOL_NETLINK, NETLINK_LIST_MEMBERSHIPS, NULL, &optlen); + if (err) { + log_err("Unexpected getsockopt(NETLINK_LIST_MEMBERSHIPS) err=%d errno=%d", + err, errno); + goto err; + } + ASSERT_EQ(optlen, 4, "Unexpected NETLINK_LIST_MEMBERSHIPS value"); + free(big_buf); close(fd); return 0; diff --git a/tools/testing/selftests/bpf/progs/sockopt_sk.c b/tools/testing/selftests/bpf/progs/sockopt_sk.c index c8d810010a946..fe1df4cd206eb 100644 --- a/tools/testing/selftests/bpf/progs/sockopt_sk.c +++ b/tools/testing/selftests/bpf/progs/sockopt_sk.c @@ -32,6 +32,12 @@ int _getsockopt(struct bpf_sockopt *ctx) __u8 *optval_end = ctx->optval_end; __u8 *optval = ctx->optval; struct sockopt_sk *storage; + struct bpf_sock *sk; + + /* Bypass AF_NETLINK. */ + sk = ctx->sk; + if (sk && sk->family == AF_NETLINK) + return 1; /* Make sure bpf_get_netns_cookie is callable. */ @@ -131,6 +137,12 @@ int _setsockopt(struct bpf_sockopt *ctx) __u8 *optval_end = ctx->optval_end; __u8 *optval = ctx->optval; struct sockopt_sk *storage; + struct bpf_sock *sk; + + /* Bypass AF_NETLINK. */ + sk = ctx->sk; + if (sk && sk->family == AF_NETLINK) + return 1; /* Make sure bpf_get_netns_cookie is callable. */ -- 2.39.2
