From: Xu Kuohai xukuohai@huawei.com
mainline inclusion from mainline-v6.12-rc1 commit d463dd9c9aa24b17ccb8ed76bdd7768baf857b48 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAYRIC CVE: CVE-2024-50063
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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Add test for lsm tail call to ensure tail call can only be used between bpf lsm progs attached to the same hook.
Signed-off-by: Xu Kuohai xukuohai@huawei.com Link: https://lore.kernel.org/r/20240719110059.797546-9-xukuohai@huaweicloud.com Signed-off-by: Alexei Starovoitov ast@kernel.org Signed-off-by: Andrii Nakryiko andrii@kernel.org Conflicts: tools/testing/selftests/bpf/prog_tests/test_lsm.c [Adapt for some minor issue] Signed-off-by: Pu Lehui pulehui@huawei.com --- .../selftests/bpf/prog_tests/test_lsm.c | 46 ++++++++++++++++++- .../selftests/bpf/progs/lsm_tailcall.c | 34 ++++++++++++++ 2 files changed, 79 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/bpf/progs/lsm_tailcall.c
diff --git a/tools/testing/selftests/bpf/prog_tests/test_lsm.c b/tools/testing/selftests/bpf/prog_tests/test_lsm.c index 6ab29226c99b..18c2e3046da3 100644 --- a/tools/testing/selftests/bpf/prog_tests/test_lsm.c +++ b/tools/testing/selftests/bpf/prog_tests/test_lsm.c @@ -13,6 +13,7 @@ #include <unistd.h>
#include "lsm.skel.h" +#include "lsm_tailcall.skel.h"
char *CMD_ARGS[] = {"true", NULL};
@@ -52,7 +53,7 @@ int exec_cmd(int *monitored_pid) return -EINVAL; }
-void test_test_lsm(void) +static void test_lsm_basic(void) { struct lsm *skel = NULL; int err, duration = 0; @@ -93,3 +94,46 @@ void test_test_lsm(void) close_prog: lsm__destroy(skel); } + +static void test_lsm_tailcall(void) +{ + struct lsm_tailcall *skel = NULL; + int map_fd, prog_fd; + int err, key; + + skel = lsm_tailcall__open_and_load(); + if (!ASSERT_OK_PTR(skel, "lsm_tailcall__skel_load")) + goto close_prog; + + map_fd = bpf_map__fd(skel->maps.jmp_table); + if (CHECK_FAIL(map_fd < 0)) + goto close_prog; + + prog_fd = bpf_program__fd(skel->progs.lsm_file_permission_prog); + if (CHECK_FAIL(prog_fd < 0)) + goto close_prog; + + key = 0; + err = bpf_map_update_elem(map_fd, &key, &prog_fd, BPF_ANY); + if (CHECK_FAIL(!err)) + goto close_prog; + + prog_fd = bpf_program__fd(skel->progs.lsm_file_alloc_security_prog); + if (CHECK_FAIL(prog_fd < 0)) + goto close_prog; + + err = bpf_map_update_elem(map_fd, &key, &prog_fd, BPF_ANY); + if (CHECK_FAIL(err)) + goto close_prog; + +close_prog: + lsm_tailcall__destroy(skel); +} + +void test_test_lsm(void) +{ + if (test__start_subtest("lsm_basic")) + test_lsm_basic(); + if (test__start_subtest("lsm_tailcall")) + test_lsm_tailcall(); +} diff --git a/tools/testing/selftests/bpf/progs/lsm_tailcall.c b/tools/testing/selftests/bpf/progs/lsm_tailcall.c new file mode 100644 index 000000000000..49c075ce2d4c --- /dev/null +++ b/tools/testing/selftests/bpf/progs/lsm_tailcall.c @@ -0,0 +1,34 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2024 Huawei Technologies Co., Ltd */ + +#include "vmlinux.h" +#include <errno.h> +#include <bpf/bpf_helpers.h> + +char _license[] SEC("license") = "GPL"; + +struct { + __uint(type, BPF_MAP_TYPE_PROG_ARRAY); + __uint(max_entries, 1); + __uint(key_size, sizeof(__u32)); + __uint(value_size, sizeof(__u32)); +} jmp_table SEC(".maps"); + +SEC("lsm/file_permission") +int lsm_file_permission_prog(void *ctx) +{ + return 0; +} + +SEC("lsm/file_alloc_security") +int lsm_file_alloc_security_prog(void *ctx) +{ + return 0; +} + +SEC("lsm/file_alloc_security") +int lsm_file_alloc_security_entry(void *ctx) +{ + bpf_tail_call_static(ctx, &jmp_table, 0); + return 0; +}