[obj2yaml] - Stop triggering UB when dumping corrupted strings.
We have a following code to find quote type:
if (isspace(S.front()) || isspace(S.back()))
...
Problem is that:
"int isspace( int ch ): The behavior is undefined if the value of
ch is not representable as unsigned char and is not equal to EOF."
(https://en.cppreference.com/w/cpp/string/byte/isspace)
This patch shows how this UB can be triggered and fixes an issue.
Differential revision: https://reviews.llvm.org/D69160
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@375404 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/llvm/Support/YAMLTraits.h b/include/llvm/Support/YAMLTraits.h
index 656020e..a3bfa7d 100644
--- a/include/llvm/Support/YAMLTraits.h
+++ b/include/llvm/Support/YAMLTraits.h
@@ -649,7 +649,8 @@
inline QuotingType needsQuotes(StringRef S) {
if (S.empty())
return QuotingType::Single;
- if (isspace(S.front()) || isspace(S.back()))
+ if (isspace(static_cast<unsigned char>(S.front())) ||
+ isspace(static_cast<unsigned char>(S.back())))
return QuotingType::Single;
if (isNull(S))
return QuotingType::Single;
diff --git a/test/tools/obj2yaml/invalid-section-name.yaml b/test/tools/obj2yaml/invalid-section-name.yaml
new file mode 100644
index 0000000..ed972ef
--- /dev/null
+++ b/test/tools/obj2yaml/invalid-section-name.yaml
@@ -0,0 +1,31 @@
+## Check we do not crash/assert when dumping a broken section name.
+## Here we replace "foo" name with a sequence of characters that
+## do are not representable as unsigned char.
+## We used to have an assert for this case before.
+
+# RUN: yaml2obj %s -o %t
+# RUN: obj2yaml %t | FileCheck %s
+
+# CHECK: --- !ELF
+# CHECK-NEXT: FileHeader:
+# CHECK-NEXT: Class: ELFCLASS64
+# CHECK-NEXT: Data: ELFDATA2LSB
+# CHECK-NEXT: Type: ET_REL
+# CHECK-NEXT: Machine: EM_X86_64
+# CHECK-NEXT: Sections:
+# CHECK-NEXT: - Name: "{{.*}}"
+# CHECK-NEXT: Type: SHT_PROGBITS
+# CHECK-NEXT: ...
+
+--- !ELF
+FileHeader:
+ Class: ELFCLASS64
+ Data: ELFDATA2LSB
+ Type: ET_REL
+ Machine: EM_X86_64
+Sections:
+ - Name: foo
+ Type: SHT_PROGBITS
+ - Name: .shstrtab
+ Type: SHT_STRTAB
+ Content: "00FEFEFEFEFEFEFEFEFEFEFEFEFEFEFEFEFEFEFEFEFEFEFEFEFEFEFEFEFEFE00"
