| commit fdd424e37abf3fa411c07f1e08fee72cfe7bb25b |
| Author: Fangrui Song <i@maskray.me> |
| Date: Tue Apr 12 11:24:19 2022 -0700 |
| |
| [ubsan] Fix print_stacktrace=1:fast_unwind_on_fatal=0 to correctly fallback to fast unwinder |
| |
| ubsan_GetStackTrace (from 52b751088b11547e0f4ef0589ebbe5e57752c68c) called by |
| ~ScopeReport leaves top/bottom zeroes in the |
| `!WillUseFastUnwind(request_fast_unwind)` code path. |
| When BufferedStackTrace::Unwind falls back to UnwindFast, |
| `if (stack_top < 4096) return;` will return early, leaving just one frame in the stack trace. |
| |
| Fix this by always initializing top/bottom like 261d6e05d5574bec753ea6b7e9a7f99229927753. |
| |
| Reviewed By: eugenis, yln |
| |
| Differential Revision: https://reviews.llvm.org/D123562 |
| |
| diff --git a/compiler-rt/lib/ubsan/ubsan_diag.cpp b/compiler-rt/lib/ubsan/ubsan_diag.cpp |
| index 8de51bc18770..3673e66539d0 100644 |
| --- a/compiler-rt/lib/ubsan/ubsan_diag.cpp |
| +++ b/compiler-rt/lib/ubsan/ubsan_diag.cpp |
| @@ -32,15 +32,13 @@ using namespace __ubsan; |
| // Windows. |
| // TODO(yln): This is a temporary workaround. GetStackTrace functions will be |
| // removed in the future. |
| -void ubsan_GetStackTrace(BufferedStackTrace *stack, uptr max_depth, |
| - uptr pc, uptr bp, void *context, bool fast) { |
| +void ubsan_GetStackTrace(BufferedStackTrace *stack, uptr max_depth, uptr pc, |
| + uptr bp, void *context, bool request_fast) { |
| uptr top = 0; |
| uptr bottom = 0; |
| - if (StackTrace::WillUseFastUnwind(fast)) { |
| - GetThreadStackTopAndBottom(false, &top, &bottom); |
| - stack->Unwind(max_depth, pc, bp, nullptr, top, bottom, true); |
| - } else |
| - stack->Unwind(max_depth, pc, bp, context, 0, 0, false); |
| + GetThreadStackTopAndBottom(false, &top, &bottom); |
| + bool fast = StackTrace::WillUseFastUnwind(request_fast); |
| + stack->Unwind(max_depth, pc, bp, context, top, bottom, fast); |
| } |
| |
| static void MaybePrintStackTrace(uptr pc, uptr bp) { |
| diff --git a/compiler-rt/test/ubsan/TestCases/Misc/Linux/diag-stacktrace.cpp b/compiler-rt/test/ubsan/TestCases/Misc/Linux/diag-stacktrace.cpp |
| new file mode 100644 |
| index 000000000000..02e7a3d9c12e |
| --- /dev/null |
| +++ b/compiler-rt/test/ubsan/TestCases/Misc/Linux/diag-stacktrace.cpp |
| @@ -0,0 +1,22 @@ |
| +/// Fast unwinder does not work with Thumb code |
| +// UNSUPPORTED: thumb |
| + |
| +// RUN: %clangxx -fsanitize=return %gmlt -O2 -fno-omit-frame-pointer -fasynchronous-unwind-tables %s -o %t |
| +// RUN: %env_ubsan_opts=print_stacktrace=1:fast_unwind_on_fatal=0 not %run %t 2>&1 | FileCheck %s |
| +// RUN: %env_ubsan_opts=print_stacktrace=1:fast_unwind_on_fatal=1 not %run %t 2>&1 | FileCheck %s |
| +// RUN: %clangxx -fsanitize=return %gmlt -O2 -fno-omit-frame-pointer -fno-exceptions -fno-asynchronous-unwind-tables %s -o %t |
| +// RUN: %env_ubsan_opts=print_stacktrace=1:fast_unwind_on_fatal=0 not %run %t 2>&1 | FileCheck %s |
| +// RUN: %env_ubsan_opts=print_stacktrace=1:fast_unwind_on_fatal=1 not %run %t 2>&1 | FileCheck %s |
| + |
| +// CHECK: runtime error: execution reached the end of a value-returning function without returning a value |
| +// CHECK-NEXT: #0 {{.*}}f() {{.*}}.cpp:[[#@LINE+1]] |
| +__attribute__((noinline)) int f() {} |
| + |
| +// CHECK-NEXT: #1 {{.*}}g() {{.*}}.cpp:[[#@LINE+1]] |
| +__attribute__((noinline)) void g() { f(); } |
| + |
| +// CHECK-NEXT: #2 {{.*}}h() {{.*}}.cpp:[[#@LINE+1]] |
| +__attribute__((noinline)) void h() { g(); } |
| + |
| +// CHECK-NEXT: #3 {{.*}}main {{.*}}.cpp:[[#@LINE+1]] |
| +int main() { h(); } |