xref: /freebsd-src/contrib/llvm-project/compiler-rt/lib/hwasan/hwasan_exceptions.cpp (revision 68d75eff68281c1b445e3010bb975eae07aac225)
1*68d75effSDimitry Andric //===-- hwasan_exceptions.cpp ---------------------------------------------===//
2*68d75effSDimitry Andric //
3*68d75effSDimitry Andric // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4*68d75effSDimitry Andric // See https://llvm.org/LICENSE.txt for license information.
5*68d75effSDimitry Andric // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6*68d75effSDimitry Andric //
7*68d75effSDimitry Andric //===----------------------------------------------------------------------===//
8*68d75effSDimitry Andric //
9*68d75effSDimitry Andric // This file is a part of HWAddressSanitizer.
10*68d75effSDimitry Andric //
11*68d75effSDimitry Andric // HWAddressSanitizer runtime.
12*68d75effSDimitry Andric //===----------------------------------------------------------------------===//
13*68d75effSDimitry Andric 
14*68d75effSDimitry Andric #include "hwasan_poisoning.h"
15*68d75effSDimitry Andric #include "sanitizer_common/sanitizer_common.h"
16*68d75effSDimitry Andric 
17*68d75effSDimitry Andric #include <unwind.h>
18*68d75effSDimitry Andric 
19*68d75effSDimitry Andric using namespace __hwasan;
20*68d75effSDimitry Andric using namespace __sanitizer;
21*68d75effSDimitry Andric 
22*68d75effSDimitry Andric typedef _Unwind_Reason_Code PersonalityFn(int version, _Unwind_Action actions,
23*68d75effSDimitry Andric                                           uint64_t exception_class,
24*68d75effSDimitry Andric                                           _Unwind_Exception* unwind_exception,
25*68d75effSDimitry Andric                                           _Unwind_Context* context);
26*68d75effSDimitry Andric 
27*68d75effSDimitry Andric // Pointers to the _Unwind_GetGR and _Unwind_GetCFA functions are passed in
28*68d75effSDimitry Andric // instead of being called directly. This is to handle cases where the unwinder
29*68d75effSDimitry Andric // is statically linked and the sanitizer runtime and the program are linked
30*68d75effSDimitry Andric // against different unwinders. The _Unwind_Context data structure is opaque so
31*68d75effSDimitry Andric // it may be incompatible between unwinders.
32*68d75effSDimitry Andric typedef _Unwind_Word GetGRFn(_Unwind_Context* context, int index);
33*68d75effSDimitry Andric typedef _Unwind_Word GetCFAFn(_Unwind_Context* context);
34*68d75effSDimitry Andric 
35*68d75effSDimitry Andric extern "C" SANITIZER_INTERFACE_ATTRIBUTE _Unwind_Reason_Code
36*68d75effSDimitry Andric __hwasan_personality_wrapper(int version, _Unwind_Action actions,
37*68d75effSDimitry Andric                              uint64_t exception_class,
38*68d75effSDimitry Andric                              _Unwind_Exception* unwind_exception,
39*68d75effSDimitry Andric                              _Unwind_Context* context,
40*68d75effSDimitry Andric                              PersonalityFn* real_personality, GetGRFn* get_gr,
41*68d75effSDimitry Andric                              GetCFAFn* get_cfa) {
42*68d75effSDimitry Andric   _Unwind_Reason_Code rc;
43*68d75effSDimitry Andric   if (real_personality)
44*68d75effSDimitry Andric     rc = real_personality(version, actions, exception_class, unwind_exception,
45*68d75effSDimitry Andric                           context);
46*68d75effSDimitry Andric   else
47*68d75effSDimitry Andric     rc = _URC_CONTINUE_UNWIND;
48*68d75effSDimitry Andric 
49*68d75effSDimitry Andric   // We only untag frames without a landing pad because landing pads are
50*68d75effSDimitry Andric   // responsible for untagging the stack themselves if they resume.
51*68d75effSDimitry Andric   //
52*68d75effSDimitry Andric   // Here we assume that the frame record appears after any locals. This is not
53*68d75effSDimitry Andric   // required by AAPCS but is a requirement for HWASAN instrumented functions.
54*68d75effSDimitry Andric   if ((actions & _UA_CLEANUP_PHASE) && rc == _URC_CONTINUE_UNWIND) {
55*68d75effSDimitry Andric #if defined(__x86_64__)
56*68d75effSDimitry Andric     uptr fp = get_gr(context, 6); // rbp
57*68d75effSDimitry Andric #elif defined(__aarch64__)
58*68d75effSDimitry Andric     uptr fp = get_gr(context, 29); // x29
59*68d75effSDimitry Andric #else
60*68d75effSDimitry Andric #error Unsupported architecture
61*68d75effSDimitry Andric #endif
62*68d75effSDimitry Andric     uptr sp = get_cfa(context);
63*68d75effSDimitry Andric     TagMemory(sp, fp - sp, 0);
64*68d75effSDimitry Andric   }
65*68d75effSDimitry Andric 
66*68d75effSDimitry Andric   return rc;
67*68d75effSDimitry Andric }
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