On 16/09/2020 1:11 pm, Amit Kachhap wrote:
On 8/31/20 4:34 PM, Boyan Karatotev wrote:
PAuth signs and verifies return addresses on the stack. It does so by
+/* check that a corrupted PAC results in SIGSEGV */ +TEST_SIGNAL(corrupt_pac, SIGSEGV) +{
- ASSERT_PAUTH_ENABLED();
- pac_corruptor();
With 8.6-Pauth extension merged in arm tree [1]. It makes sense to verify PAC corruption for both SIGSEGV and SIGILL signals.
Code something like below handles both the cases.
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int exec_sign_all(struct signatures *signed_vals, size_t val) @@ -187,12 +188,29 @@ int exec_sign_all(struct signatures *signed_vals, size_t val) return 0; }
-/* check that a corrupted PAC results in SIGSEGV */ -TEST_SIGNAL(corrupt_pac, SIGSEGV) +sigjmp_buf jmpbuf; +void pac_signal_handler(int signum, siginfo_t *si, void *uc) {
ASSERT_PAUTH_ENABLED();
if (signum == SIGSEGV || signum == SIGILL) {siglongjmp(jmpbuf, 1);}+}
+/* check that a corrupted PAC results in SIGSEGV or SIGILL */ +TEST(corrupt_pac) +{
struct sigaction sa;
pac_corruptor();
ASSERT_PAUTH_ENABLED();if (sigsetjmp(jmpbuf, 1) == 0) {sa.sa_sigaction = pac_signal_handler;sa.sa_flags = SA_SIGINFO;sigemptyset(&sa.sa_mask);sigaction(SIGSEGV, &sa, NULL);sigaction(SIGILL, &sa, NULL);pac_corruptor();ASSERT_TRUE(0) TH_LOG("SIGSEGV/SIGILL signal did notoccur");
}}
/* @@ -265,7 +283,7 @@ TEST(single_thread_different_keys)
tmp = n_same_single_set(&signed_vals, nkeys);
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Thanks, Amit Daniel
[1]:
https://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git/log/?h=for-n...
Okay, I will add this and post it with the next version.
Regards, Boyan