From d02d8986a7688d3f0ff6ef61aa6beb41427692eb Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Micka=C3=ABl=20Sala=C3=BCn?= Date: Fri, 10 Feb 2017 00:21:37 +0100 Subject: [PATCH] bpf: Always test unprivileged programs MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If selftests are run as root, then execute the unprivileged checks as well. This switch from 243 to 368 tests. The test numbers are suffixed with "/u" when executed as unprivileged or with "/p" when executed as privileged. The geteuid() check is replaced with a capability check. Handling capabilities requires the libcap dependency. Signed-off-by: Mickaël Salaün Acked-by: Alexei Starovoitov Acked-by: Daniel Borkmann Cc: Shuah Khan Signed-off-by: David S. Miller --- tools/testing/selftests/bpf/Makefile | 2 +- tools/testing/selftests/bpf/test_verifier.c | 68 +++++++++++++++++++-- 2 files changed, 64 insertions(+), 6 deletions(-) diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile index c470c7301636..f3d65ad53494 100644 --- a/tools/testing/selftests/bpf/Makefile +++ b/tools/testing/selftests/bpf/Makefile @@ -1,4 +1,4 @@ -CFLAGS += -Wall -O2 -I../../../include/uapi +CFLAGS += -Wall -O2 -lcap -I../../../include/uapi test_objs = test_verifier test_tag test_maps test_lru_map test_lpm_map diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c index 71f6407cde60..878bd60da376 100644 --- a/tools/testing/selftests/bpf/test_verifier.c +++ b/tools/testing/selftests/bpf/test_verifier.c @@ -16,6 +16,7 @@ #include #include +#include #include #include @@ -4574,6 +4575,55 @@ fail_log: goto close_fds; } +static bool is_admin(void) +{ + cap_t caps; + cap_flag_value_t sysadmin = CAP_CLEAR; + const cap_value_t cap_val = CAP_SYS_ADMIN; + + if (!CAP_IS_SUPPORTED(CAP_SETFCAP)) { + perror("cap_get_flag"); + return false; + } + caps = cap_get_proc(); + if (!caps) { + perror("cap_get_proc"); + return false; + } + if (cap_get_flag(caps, cap_val, CAP_EFFECTIVE, &sysadmin)) + perror("cap_get_flag"); + if (cap_free(caps)) + perror("cap_free"); + return (sysadmin == CAP_SET); +} + +static int set_admin(bool admin) +{ + cap_t caps; + const cap_value_t cap_val = CAP_SYS_ADMIN; + int ret = -1; + + caps = cap_get_proc(); + if (!caps) { + perror("cap_get_proc"); + return -1; + } + if (cap_set_flag(caps, CAP_EFFECTIVE, 1, &cap_val, + admin ? CAP_SET : CAP_CLEAR)) { + perror("cap_set_flag"); + goto out; + } + if (cap_set_proc(caps)) { + perror("cap_set_proc"); + goto out; + } + ret = 0; +out: + if (cap_free(caps)) + perror("cap_free"); + return ret; +} + static int do_test(bool unpriv, unsigned int from, unsigned int to) { int i, passes = 0, errors = 0; @@ -4584,11 +4634,19 @@ static int do_test(bool unpriv, unsigned int from, unsigned int to) /* Program types that are not supported by non-root we * skip right away. */ - if (unpriv && test->prog_type) - continue; + if (!test->prog_type) { + if (!unpriv) + set_admin(false); + printf("#%d/u %s ", i, test->descr); + do_test_single(test, true, &passes, &errors); + if (!unpriv) + set_admin(true); + } - printf("#%d %s ", i, test->descr); - do_test_single(test, unpriv, &passes, &errors); + if (!unpriv) { + printf("#%d/p %s ", i, test->descr); + do_test_single(test, false, &passes, &errors); + } } printf("Summary: %d PASSED, %d FAILED\n", passes, errors); @@ -4600,7 +4658,7 @@ int main(int argc, char **argv) struct rlimit rinf = { RLIM_INFINITY, RLIM_INFINITY }; struct rlimit rlim = { 1 << 20, 1 << 20 }; unsigned int from = 0, to = ARRAY_SIZE(tests); - bool unpriv = geteuid() != 0; + bool unpriv = !is_admin(); if (argc == 3) { unsigned int l = atoi(argv[argc - 2]);