[src/trunk]: src/sys/arch/aarch64/include Provide a kasan_md_unwind

[skrll <skrll%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/369d842a22f0
branches:  trunk
changeset: 836727:369d842a22f0
user:      skrll <skrll%NetBSD.org@localhost>
date:      Fri Nov 02 08:18:18 2018 +0000

description:
Provide a kasan_md_unwind

OK maxv

diffstat:

 sys/arch/aarch64/include/asan.h |  59 +++++++++++++++++++++++++++++++++++++++-
 1 files changed, 57 insertions(+), 2 deletions(-)

diffs (77 lines):

diff -r 334d1e260dee -r 369d842a22f0 sys/arch/aarch64/include/asan.h
--- a/sys/arch/aarch64/include/asan.h   Fri Nov 02 08:16:49 2018 +0000
+++ b/sys/arch/aarch64/include/asan.h   Fri Nov 02 08:18:18 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: asan.h,v 1.1 2018/11/01 20:34:50 maxv Exp $    */
+/*     $NetBSD: asan.h,v 1.2 2018/11/02 08:18:18 skrll Exp $   */
 
 /*
  * Copyright (c) 2018 The NetBSD Foundation, Inc.
@@ -30,6 +30,8 @@
  */
 
 #include <sys/atomic.h>
+#include <sys/ksyms.h>
+
 #include <aarch64/pmap.h>
 #include <aarch64/vmparam.h>
 #include <aarch64/cpufunc.h>
@@ -133,4 +135,57 @@
            eva - VM_MIN_KERNEL_ADDRESS);
 }
 
-#define kasan_md_unwind()      __nothing
+static inline bool
+__md_unwind_end(const char *name)
+{
+       if (!strncmp(name, "el0_trap", 8) ||
+           !strncmp(name, "el1_trap", 8)) {
+               return true;
+       }
+
+       return false;
+}
+
+static void
+kasan_md_unwind(void)
+{
+       uint64_t lr, *fp;
+       const char *mod;
+       const char *sym;
+       size_t nsym;
+       int error;
+
+       fp = (uint64_t *)__builtin_frame_address(0);
+       nsym = 0;
+
+       while (1) {
+               /*
+                * normal stack frame
+                *  fp[0]  saved fp(x29) value
+                *  fp[1]  saved lr(x30) value
+                */
+               lr = fp[1];
+
+               if (lr < VM_MIN_KERNEL_ADDRESS) {
+                       break;
+               }
+               error = ksyms_getname(&mod, &sym, (vaddr_t)lr, KSYMS_PROC);
+               if (error) {
+                       break;
+               }
+               printf("#%zu %p in %s <%s>\n", nsym, (void *)lr, sym, mod);
+               if (__md_unwind_end(sym)) {
+                       break;
+               }
+
+               fp = (uint64_t *)fp[0];
+               if (fp == NULL) {
+                       break;
+               }
+               nsym++;
+
+               if (nsym >= 15) {
+                       break;
+               }
+       }
+}