RPCS3/llvm-mirror
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-23 19:23:23 +01:00
Code Issues Projects Releases Wiki Activity

[SanitizerCoverage] Clang crashes if user declares __sancov_lowest_stack variable

Browse Source 
Summary:
If the user declares or defines `__sancov_lowest_stack` with an
unexpected type, then `getOrInsertGlobal` inserts a bitcast and the
following cast fails:
```
Constant *SanCovLowestStackConstant =
       M.getOrInsertGlobal(SanCovLowestStackName, IntptrTy);
SanCovLowestStack = cast<GlobalVariable>(SanCovLowestStackConstant);
```

This variable is a SanitizerCoverage implementation detail and the user
should generally never have a need to access it, so we emit an error
now.

rdar://problem/44143130

Reviewers: morehouse

Differential Revision: https://reviews.llvm.org/D57633

llvm-svn: 353100
This commit is contained in:
Julian Lettner 2019-02-04 22:06:30 +00:00
parent 1b78df33e7
commit a0346fe540
2 changed files with 18 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
lib/Transforms/Instrumentation/SanitizerCoverage.cpp
View File

@ -377,7 +377,12 @@ bool SanitizerCoverageModule::runOnModule(Module &M) {
Constant *SanCovLowestStackConstant =
M.getOrInsertGlobal(SanCovLowestStackName, IntptrTy);
SanCovLowestStack = cast<GlobalVariable>(SanCovLowestStackConstant);
SanCovLowestStack = dyn_cast<GlobalVariable>(SanCovLowestStackConstant);
if (!SanCovLowestStack) {
C->emitError(StringRef("'") + SanCovLowestStackName +
"' should not be declared by the user");
return true;
}
SanCovLowestStack->setThreadLocalMode(
GlobalValue::ThreadLocalMode::InitialExecTLSModel);
if (Options.StackDepth && !SanCovLowestStack->isDeclaration())

12
test/Instrumentation/SanitizerCoverage/stack-depth-variable-declared-by-user.ll Normal file
View File

@ -0,0 +1,12 @@
; Ensure that we terminate with a useful error message (instead of crash) if the
; user declares `__sancov_lowest_stack` with an unexpected type.
; RUN: not opt < %s -sancov -sanitizer-coverage-level=1 \
; RUN: -sanitizer-coverage-stack-depth -S 2>&1 | FileCheck %s
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
; Wrong type: i32 instead of expected i64
@__sancov_lowest_stack = thread_local global i32 0
; CHECK: error: '__sancov_lowest_stack' should not be declared by the user