1 files changed, 269 insertions, 0 deletions
diff --git a/test/syscalls/linux/sigprocmask.cc b/test/syscalls/linux/sigprocmask.cc
new file mode 100644
index 000000000..a603fc1d1
--- /dev/null
+++ b/test/syscalls/linux/sigprocmask.cc
@@ -0,0 +1,269 @@
+// Copyright 2018 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <signal.h>
+#include <stddef.h>
+#include <sys/syscall.h>
+#include <unistd.h>
+
+#include "gtest/gtest.h"
+#include "test/util/signal_util.h"
+#include "test/util/test_util.h"
+
+namespace gvisor {
+namespace testing {
+
+namespace {
+
+// Signals numbers used for testing.
+static constexpr int kTestSignal1 = SIGUSR1;
+static constexpr int kTestSignal2 = SIGUSR2;
+
+static int raw_sigprocmask(int how, const sigset_t* set, sigset_t* oldset) {
+  return syscall(SYS_rt_sigprocmask, how, set, oldset, _NSIG / 8);
+}
+
+// count of the number of signals received
+int signal_count[kMaxSignal + 1];
+
+// signal handler increments the signal counter
+void SigHandler(int sig, siginfo_t* info, void* context) {
+  TEST_CHECK(sig > 0 && sig <= kMaxSignal);
+  signal_count[sig] += 1;
+}
+
+// The test fixture saves and restores the signal mask and
+// sets up handlers for kTestSignal1 and kTestSignal2.
+class SigProcMaskTest : public ::testing::Test {
+ protected:
+  void SetUp() override {
+    // Save the current signal mask.
+    EXPECT_THAT(raw_sigprocmask(SIG_SETMASK, nullptr, &mask_),
+                SyscallSucceeds());
+
+    // Setup signal handlers for kTestSignal1 and kTestSignal2.
+    struct sigaction sa;
+    sa.sa_sigaction = SigHandler;
+    sigfillset(&sa.sa_mask);
+    sa.sa_flags = SA_SIGINFO;
+    EXPECT_THAT(sigaction(kTestSignal1, &sa, &sa_test_sig_1_),
+                SyscallSucceeds());
+    EXPECT_THAT(sigaction(kTestSignal2, &sa, &sa_test_sig_2_),
+                SyscallSucceeds());
+
+    // Clear the signal counters.
+    memset(signal_count, 0, sizeof(signal_count));
+  }
+
+  void TearDown() override {
+    // Restore the signal mask.
+    EXPECT_THAT(raw_sigprocmask(SIG_SETMASK, &mask_, nullptr),
+                SyscallSucceeds());
+
+    // Restore the signal handlers for kTestSignal1 and kTestSignal2.
+    EXPECT_THAT(sigaction(kTestSignal1, &sa_test_sig_1_, nullptr),
+                SyscallSucceeds());
+    EXPECT_THAT(sigaction(kTestSignal2, &sa_test_sig_2_, nullptr),
+                SyscallSucceeds());
+  }
+
+ private:
+  sigset_t mask_;
+  struct sigaction sa_test_sig_1_;
+  struct sigaction sa_test_sig_2_;
+};
+
+// Both sigsets nullptr should succeed and do nothing.
+TEST_F(SigProcMaskTest, NullAddress) {
+  EXPECT_THAT(raw_sigprocmask(SIG_BLOCK, nullptr, NULL), SyscallSucceeds());
+  EXPECT_THAT(raw_sigprocmask(SIG_UNBLOCK, nullptr, NULL), SyscallSucceeds());
+  EXPECT_THAT(raw_sigprocmask(SIG_SETMASK, nullptr, NULL), SyscallSucceeds());
+}
+
+// Bad address for either sigset should fail with EFAULT.
+TEST_F(SigProcMaskTest, BadAddress) {
+  sigset_t* bad_addr = reinterpret_cast<sigset_t*>(-1);
+
+  EXPECT_THAT(raw_sigprocmask(SIG_SETMASK, bad_addr, nullptr),
+              SyscallFailsWithErrno(EFAULT));
+
+  EXPECT_THAT(raw_sigprocmask(SIG_SETMASK, nullptr, bad_addr),
+              SyscallFailsWithErrno(EFAULT));
+}
+
+// Bad value of the "how" parameter should fail with EINVAL.
+TEST_F(SigProcMaskTest, BadParameter) {
+  int bad_param_1 = -1;
+  int bad_param_2 = 42;
+
+  sigset_t set1;
+  sigemptyset(&set1);
+
+  EXPECT_THAT(raw_sigprocmask(bad_param_1, &set1, nullptr),
+              SyscallFailsWithErrno(EINVAL));
+
+  EXPECT_THAT(raw_sigprocmask(bad_param_2, &set1, nullptr),
+              SyscallFailsWithErrno(EINVAL));
+}
+
+// Check that we can get the current signal mask.
+TEST_F(SigProcMaskTest, GetMask) {
+  sigset_t set1;
+  sigset_t set2;
+
+  sigemptyset(&set1);
+  sigfillset(&set2);
+  EXPECT_THAT(raw_sigprocmask(SIG_SETMASK, nullptr, &set1), SyscallSucceeds());
+  EXPECT_THAT(raw_sigprocmask(SIG_SETMASK, nullptr, &set2), SyscallSucceeds());
+  EXPECT_THAT(set1, EqualsSigset(set2));
+}
+
+// Check that we can set the signal mask.
+TEST_F(SigProcMaskTest, SetMask) {
+  sigset_t actual;
+  sigset_t expected;
+
+  // Try to mask all signals
+  sigfillset(&expected);
+  EXPECT_THAT(raw_sigprocmask(SIG_SETMASK, &expected, nullptr),
+              SyscallSucceeds());
+  EXPECT_THAT(raw_sigprocmask(SIG_SETMASK, nullptr, &actual),
+              SyscallSucceeds());
+  // sigprocmask() should have silently ignored SIGKILL and SIGSTOP.
+  sigdelset(&expected, SIGSTOP);
+  sigdelset(&expected, SIGKILL);
+  EXPECT_THAT(actual, EqualsSigset(expected));
+
+  // Try to clear the signal mask
+  sigemptyset(&expected);
+  EXPECT_THAT(raw_sigprocmask(SIG_SETMASK, &expected, nullptr),
+              SyscallSucceeds());
+  EXPECT_THAT(raw_sigprocmask(SIG_SETMASK, nullptr, &actual),
+              SyscallSucceeds());
+  EXPECT_THAT(actual, EqualsSigset(expected));
+
+  // Try to set a mask with one signal.
+  sigemptyset(&expected);
+  sigaddset(&expected, kTestSignal1);
+  EXPECT_THAT(raw_sigprocmask(SIG_SETMASK, &expected, nullptr),
+              SyscallSucceeds());
+  EXPECT_THAT(raw_sigprocmask(SIG_SETMASK, nullptr, &actual),
+              SyscallSucceeds());
+  EXPECT_THAT(actual, EqualsSigset(expected));
+}
+
+// Check that we can add and remove signals.
+TEST_F(SigProcMaskTest, BlockUnblock) {
+  sigset_t actual;
+  sigset_t expected;
+
+  // Try to set a mask with one signal.
+  sigemptyset(&expected);
+  sigaddset(&expected, kTestSignal1);
+  EXPECT_THAT(raw_sigprocmask(SIG_SETMASK, &expected, nullptr),
+              SyscallSucceeds());
+  EXPECT_THAT(raw_sigprocmask(SIG_SETMASK, nullptr, &actual),
+              SyscallSucceeds());
+  EXPECT_THAT(actual, EqualsSigset(expected));
+
+  // Try to add another signal.
+  sigset_t block;
+  sigemptyset(&block);
+  sigaddset(&block, kTestSignal2);
+  EXPECT_THAT(raw_sigprocmask(SIG_BLOCK, &block, nullptr), SyscallSucceeds());
+  EXPECT_THAT(raw_sigprocmask(SIG_SETMASK, nullptr, &actual),
+              SyscallSucceeds());
+  sigaddset(&expected, kTestSignal2);
+  EXPECT_THAT(actual, EqualsSigset(expected));
+
+  // Try to remove a signal.
+  sigset_t unblock;
+  sigemptyset(&unblock);
+  sigaddset(&unblock, kTestSignal1);
+  EXPECT_THAT(raw_sigprocmask(SIG_UNBLOCK, &unblock, nullptr),
+              SyscallSucceeds());
+  EXPECT_THAT(raw_sigprocmask(SIG_SETMASK, nullptr, &actual),
+              SyscallSucceeds());
+  sigdelset(&expected, kTestSignal1);
+  EXPECT_THAT(actual, EqualsSigset(expected));
+}
+
+// Test that the signal mask actually blocks signals.
+TEST_F(SigProcMaskTest, SignalHandler) {
+  sigset_t mask;
+
+  // clear the signal mask
+  sigemptyset(&mask);
+  EXPECT_THAT(raw_sigprocmask(SIG_SETMASK, &mask, nullptr), SyscallSucceeds());
+
+  // Check the initial signal counts.
+  EXPECT_EQ(0, signal_count[kTestSignal1]);
+  EXPECT_EQ(0, signal_count[kTestSignal2]);
+
+  // Check that both kTestSignal1 and kTestSignal2 are not blocked.
+  raise(kTestSignal1);
+  raise(kTestSignal2);
+  EXPECT_EQ(1, signal_count[kTestSignal1]);
+  EXPECT_EQ(1, signal_count[kTestSignal2]);
+
+  // Block kTestSignal1.
+  sigaddset(&mask, kTestSignal1);
+  EXPECT_THAT(raw_sigprocmask(SIG_BLOCK, &mask, nullptr), SyscallSucceeds());
+
+  // Check that kTestSignal1 is blocked.
+  raise(kTestSignal1);
+  raise(kTestSignal2);
+  EXPECT_EQ(1, signal_count[kTestSignal1]);
+  EXPECT_EQ(2, signal_count[kTestSignal2]);
+
+  // Unblock kTestSignal1.
+  sigaddset(&mask, kTestSignal1);
+  EXPECT_THAT(raw_sigprocmask(SIG_UNBLOCK, &mask, nullptr), SyscallSucceeds());
+
+  // Check that the unblocked kTestSignal1 has been delivered.
+  EXPECT_EQ(2, signal_count[kTestSignal1]);
+  EXPECT_EQ(2, signal_count[kTestSignal2]);
+}
+
+// Check that sigprocmask correctly handles aliasing of the set and oldset
+// pointers. Regression test for b/30502311.
+TEST_F(SigProcMaskTest, AliasedSets) {
+  sigset_t mask;
+
+  // Set a mask in which only kTestSignal1 is blocked.
+  sigset_t mask1;
+  sigemptyset(&mask1);
+  sigaddset(&mask1, kTestSignal1);
+  mask = mask1;
+  ASSERT_THAT(raw_sigprocmask(SIG_SETMASK, &mask, nullptr), SyscallSucceeds());
+
+  // Exchange it with a mask in which only kTestSignal2 is blocked.
+  sigset_t mask2;
+  sigemptyset(&mask2);
+  sigaddset(&mask2, kTestSignal2);
+  mask = mask2;
+  ASSERT_THAT(raw_sigprocmask(SIG_SETMASK, &mask, &mask), SyscallSucceeds());
+
+  // Check that the exchange succeeeded:
+  // mask should now contain the previously-set mask blocking only kTestSignal1.
+  EXPECT_THAT(mask, EqualsSigset(mask1));
+  // The current mask should block only kTestSignal2.
+  ASSERT_THAT(raw_sigprocmask(0, nullptr, &mask), SyscallSucceeds());
+  EXPECT_THAT(mask, EqualsSigset(mask2));
+}
+
+}  // namespace
+
+}  // namespace testing
+}  // namespace gvisor