From: Masami Hiramatsu mhiramat@kernel.org

[ Upstream commit 295c4e21cf27ac9af542140e3e797df9e0cf7b5f ]

Check the return value of setuid() and setgid(). This fixes the following warnings and improves test result.

safesetid-test.c: In function ‘main’: safesetid-test.c:294:2: warning: ignoring return value of ‘setuid’, declared with attribute warn_unused_result [-Wunused-result] setuid(NO_POLICY_USER); ^~~~~~~~~~~~~~~~~~~~~~ safesetid-test.c:295:2: warning: ignoring return value of ‘setgid’, declared with attribute warn_unused_result [-Wunused-result] setgid(NO_POLICY_USER); ^~~~~~~~~~~~~~~~~~~~~~ safesetid-test.c:309:2: warning: ignoring return value of ‘setuid’, declared with attribute warn_unused_result [-Wunused-result] setuid(RESTRICTED_PARENT); ^~~~~~~~~~~~~~~~~~~~~~~~~ safesetid-test.c:310:2: warning: ignoring return value of ‘setgid’, declared with attribute warn_unused_result [-Wunused-result] setgid(RESTRICTED_PARENT); ^~~~~~~~~~~~~~~~~~~~~~~~~ safesetid-test.c: In function ‘test_setuid’: safesetid-test.c:216:3: warning: ignoring return value of ‘setuid’, declared with attribute warn_unused_result [-Wunused-result] setuid(child_uid); ^~~~~~~~~~~~~~~~~

Fixes: c67e8ec03f3f ("LSM: SafeSetID: add selftest") Signed-off-by: Masami Hiramatsu mhiramat@kernel.org Signed-off-by: Shuah Khan skhan@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- .../testing/selftests/safesetid/safesetid-test.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-)

diff --git a/tools/testing/selftests/safesetid/safesetid-test.c b/tools/testing/selftests/safesetid/safesetid-test.c index 8f40c6ecdad1..0c4d50644c13 100644 --- a/tools/testing/selftests/safesetid/safesetid-test.c +++ b/tools/testing/selftests/safesetid/safesetid-test.c @@ -213,7 +213,8 @@ static void test_setuid(uid_t child_uid, bool expect_success) }

if (cpid == 0) { /* Code executed by child */ - setuid(child_uid); + if (setuid(child_uid) < 0) + exit(EXIT_FAILURE); if (getuid() == child_uid) exit(EXIT_SUCCESS); else @@ -291,8 +292,10 @@ int main(int argc, char **argv)

// First test to make sure we can write userns mappings from a user // that doesn't have any restrictions (as long as it has CAP_SETUID); - setuid(NO_POLICY_USER); - setgid(NO_POLICY_USER); + if (setuid(NO_POLICY_USER) < 0) + die("Error with set uid(%d)\n", NO_POLICY_USER); + if (setgid(NO_POLICY_USER) < 0) + die("Error with set gid(%d)\n", NO_POLICY_USER);

// Take away all but setid caps drop_caps(true); @@ -306,8 +309,10 @@ int main(int argc, char **argv) die("test_userns failed when it should work\n"); }

- setuid(RESTRICTED_PARENT); - setgid(RESTRICTED_PARENT); + if (setuid(RESTRICTED_PARENT) < 0) + die("Error with set uid(%d)\n", RESTRICTED_PARENT); + if (setgid(RESTRICTED_PARENT) < 0) + die("Error with set gid(%d)\n", RESTRICTED_PARENT);

test_setuid(ROOT_USER, false); test_setuid(ALLOWED_CHILD1, true);