Fix the leak of signal stack space in a test.

PiperOrigin-RevId: 551029334

e2e_tests/testdata/fuzz_tests_for_functional_testing.cc

diff --git a/e2e_tests/testdata/fuzz_tests_for_functional_testing.cc b/e2e_tests/testdata/fuzz_tests_for_functional_testing.cc
index d4d2530..15d4ee8 100644
--- a/e2e_tests/testdata/fuzz_tests_for_functional_testing.cc
+++ b/e2e_tests/testdata/fuzz_tests_for_functional_testing.cc
@@ -706,6 +706,13 @@
   raise(SIGUSR1);
   // Just make sure the signal handler ran.
   FUZZTEST_INTERNAL_CHECK(dummy_to_trigger_cmp_in_handler != 0, "");
+  // Disable and free the previous signal stack.
+  stack_t sigstk = {};
+  sigstk.ss_flags = SS_DISABLE;
+  stack_t prev_sigstk;
+  FUZZTEST_INTERNAL_CHECK(sigaltstack(&sigstk, &prev_sigstk) == 0, errno);
+  free(prev_sigstk.ss_sp);
+
   if (i == 123456789) {
     std::abort();
   }