From bc97f9f64f8a4a84d0d06949749e9dbec143b9f5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Alex=20Benn=C3=A9e?= <alex.bennee@linaro.org>
Date: Tue, 25 Feb 2020 12:47:10 +0000
Subject: [PATCH] tests/tcg: take into account expected clashes pauth-4
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Pointer authentication isn't perfect so measure the percentage of
failed checks. As we want to vary the pointer we work through a bunch
of different addresses.
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Robert Foley <robert.foley@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20200225124710.14152-20-alex.bennee@linaro.org>
---
tests/tcg/aarch64/pauth-4.c | 54 +++++++++++++++++++++++++------------
1 file changed, 37 insertions(+), 17 deletions(-)
diff --git a/tests/tcg/aarch64/pauth-4.c b/tests/tcg/aarch64/pauth-4.c
index 1040e92aec..24a639e36c 100644
--- a/tests/tcg/aarch64/pauth-4.c
+++ b/tests/tcg/aarch64/pauth-4.c
@@ -1,25 +1,45 @@
#include <stdint.h>
#include <assert.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#define TESTS 1000
int main()
{
- uintptr_t x, y;
+ int i, count = 0;
+ float perc;
+ void *base = malloc(TESTS);
- asm("mov %0, lr\n\t"
- "pacia %0, sp\n\t" /* sigill if pauth not supported */
- "eor %0, %0, #4\n\t" /* corrupt single bit */
- "mov %1, %0\n\t"
- "autia %1, sp\n\t" /* validate corrupted pointer */
- "xpaci %0\n\t" /* strip pac from corrupted pointer */
- : "=r"(x), "=r"(y));
+ for (i = 0; i < TESTS; i++) {
+ uintptr_t in, x, y;
- /*
- * Once stripped, the corrupted pointer is of the form 0x0000...wxyz.
- * We expect the autia to indicate failure, producing a pointer of the
- * form 0x000e....wxyz. Use xpaci and != for the test, rather than
- * extracting explicit bits from the top, because the location of the
- * error code "e" depends on the configuration of virtual memory.
- */
- assert(x != y);
- return 0;
+ in = i + (uintptr_t) base;
+
+ asm("mov %0, %[in]\n\t"
+ "pacia %0, sp\n\t" /* sigill if pauth not supported */
+ "eor %0, %0, #4\n\t" /* corrupt single bit */
+ "mov %1, %0\n\t"
+ "autia %1, sp\n\t" /* validate corrupted pointer */
+ "xpaci %0\n\t" /* strip pac from corrupted pointer */
+ : /* out */ "=r"(x), "=r"(y)
+ : /* in */ [in] "r" (in)
+ : /* clobbers */);
+
+ /*
+ * Once stripped, the corrupted pointer is of the form 0x0000...wxyz.
+ * We expect the autia to indicate failure, producing a pointer of the
+ * form 0x000e....wxyz. Use xpaci and != for the test, rather than
+ * extracting explicit bits from the top, because the location of the
+ * error code "e" depends on the configuration of virtual memory.
+ */
+ if (x != y) {
+ count++;
+ }
+
+ }
+ perc = (float) count / (float) TESTS;
+ printf("Checks Passed: %0.2f%%", perc * 100.0);
+ assert(perc > 0.95);
+ return 0;
}