[llvm] cb3a598 - [DebugInfo] Don't error for zero-length arange entries
James Henderson via llvm-commits
llvm-commits at lists.llvm.org
Mon Aug 10 04:50:22 PDT 2020
Author: James Henderson
Date: 2020-08-10T12:48:31+01:00
New Revision: cb3a598c87db2db997401b82dfb3f7f80707194e
URL: https://github.com/llvm/llvm-project/commit/cb3a598c87db2db997401b82dfb3f7f80707194e
DIFF: https://github.com/llvm/llvm-project/commit/cb3a598c87db2db997401b82dfb3f7f80707194e.diff
LOG: [DebugInfo] Don't error for zero-length arange entries
Although the DWARF specification states that .debug_aranges entries
can't have length zero, these can occur in the wild. There's no
particular reason to enforce this part of the spec, since functionally
they have no impact. The patch removes the error and introduces a new
warning for premature terminator entries which does not stop parsing.
Fixes https://bugs.llvm.org/show_bug.cgi?id=46805. See also
https://reviews.llvm.org/D71932 which originally introduced the error.
Reviewed by: ikudrin, dblaikie
Differential Revision: https://reviews.llvm.org/D85313
Added:
Modified:
llvm/include/llvm/DebugInfo/DWARF/DWARFDebugArangeSet.h
llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
llvm/lib/DebugInfo/DWARF/DWARFDebugArangeSet.cpp
llvm/lib/DebugInfo/DWARF/DWARFDebugAranges.cpp
llvm/unittests/DebugInfo/DWARF/DWARFDebugArangeSetTest.cpp
Removed:
################################################################################
diff --git a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugArangeSet.h b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugArangeSet.h
index 0681a2e33a50..3d5852ee1518 100644
--- a/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugArangeSet.h
+++ b/llvm/include/llvm/DebugInfo/DWARF/DWARFDebugArangeSet.h
@@ -60,7 +60,8 @@ class DWARFDebugArangeSet {
DWARFDebugArangeSet() { clear(); }
void clear();
- Error extract(DWARFDataExtractor data, uint64_t *offset_ptr);
+ Error extract(DWARFDataExtractor data, uint64_t *offset_ptr,
+ function_ref<void(Error)> WarningHandler);
void dump(raw_ostream &OS) const;
uint64_t getCompileUnitDIEOffset() const { return HeaderData.CuOffset; }
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
index bf6219497770..3bcde8fafb1f 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
@@ -502,7 +502,8 @@ void DWARFContext::dump(
0);
DWARFDebugArangeSet set;
while (arangesData.isValidOffset(offset)) {
- if (Error E = set.extract(arangesData, &offset)) {
+ if (Error E =
+ set.extract(arangesData, &offset, DumpOpts.WarningHandler)) {
RecoverableErrorHandler(std::move(E));
break;
}
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDebugArangeSet.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDebugArangeSet.cpp
index 608fc0388af0..381dd476cd58 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFDebugArangeSet.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFDebugArangeSet.cpp
@@ -32,7 +32,8 @@ void DWARFDebugArangeSet::clear() {
}
Error DWARFDebugArangeSet::extract(DWARFDataExtractor data,
- uint64_t *offset_ptr) {
+ uint64_t *offset_ptr,
+ function_ref<void(Error)> WarningHandler) {
assert(data.isValidOffset(*offset_ptr));
ArangeDescriptors.clear();
Offset = *offset_ptr;
@@ -132,19 +133,20 @@ Error DWARFDebugArangeSet::extract(DWARFDataExtractor data,
uint64_t end_offset = Offset + full_length;
while (*offset_ptr < end_offset) {
+ uint64_t EntryOffset = *offset_ptr;
arangeDescriptor.Address = data.getUnsigned(offset_ptr, HeaderData.AddrSize);
arangeDescriptor.Length = data.getUnsigned(offset_ptr, HeaderData.AddrSize);
- if (arangeDescriptor.Length == 0) {
- // Each set of tuples is terminated by a 0 for the address and 0
- // for the length.
- if (arangeDescriptor.Address == 0 && *offset_ptr == end_offset)
+ // Each set of tuples is terminated by a 0 for the address and 0
+ // for the length.
+ if (arangeDescriptor.Length == 0 && arangeDescriptor.Address == 0) {
+ if (*offset_ptr == end_offset)
return ErrorSuccess();
- return createStringError(
+ WarningHandler(createStringError(
errc::invalid_argument,
"address range table at offset 0x%" PRIx64
- " has an invalid tuple (length = 0) at offset 0x%" PRIx64,
- Offset, *offset_ptr - tuple_size);
+ " has a premature terminator entry at offset 0x%" PRIx64,
+ Offset, EntryOffset));
}
ArangeDescriptors.push_back(arangeDescriptor);
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDebugAranges.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDebugAranges.cpp
index e8ed63075055..e0db469752cd 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFDebugAranges.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFDebugAranges.cpp
@@ -28,7 +28,8 @@ void DWARFDebugAranges::extract(
DWARFDebugArangeSet Set;
while (DebugArangesData.isValidOffset(Offset)) {
- if (Error E = Set.extract(DebugArangesData, &Offset)) {
+ if (Error E =
+ Set.extract(DebugArangesData, &Offset, RecoverableErrorHandler)) {
RecoverableErrorHandler(std::move(E));
return;
}
diff --git a/llvm/unittests/DebugInfo/DWARF/DWARFDebugArangeSetTest.cpp b/llvm/unittests/DebugInfo/DWARF/DWARFDebugArangeSetTest.cpp
index 4ec9c5d1c0be..face8ec024fa 100644
--- a/llvm/unittests/DebugInfo/DWARF/DWARFDebugArangeSetTest.cpp
+++ b/llvm/unittests/DebugInfo/DWARF/DWARFDebugArangeSetTest.cpp
@@ -7,12 +7,23 @@
//===----------------------------------------------------------------------===//
#include "llvm/DebugInfo/DWARF/DWARFDebugArangeSet.h"
+#include "llvm/Testing/Support/Error.h"
#include "gtest/gtest.h"
using namespace llvm;
namespace {
+struct WarningHandler {
+ ~WarningHandler() { EXPECT_THAT_ERROR(std::move(Err), Succeeded()); }
+
+ void operator()(Error E) { Err = joinErrors(std::move(Err), std::move(E)); }
+
+ Error getWarning() { return std::move(Err); }
+
+ Error Err = Error::success();
+};
+
template <size_t SecSize>
void ExpectExtractError(const char (&SecDataRaw)[SecSize],
const char *ErrorMessage) {
@@ -21,7 +32,8 @@ void ExpectExtractError(const char (&SecDataRaw)[SecSize],
/* AddressSize = */ 4);
DWARFDebugArangeSet Set;
uint64_t Offset = 0;
- Error E = Set.extract(Extractor, &Offset);
+ WarningHandler Warnings;
+ Error E = Set.extract(Extractor, &Offset, Warnings);
ASSERT_TRUE(E.operator bool());
EXPECT_STREQ(ErrorMessage, toString(std::move(E)).c_str());
}
@@ -166,9 +178,9 @@ TEST(DWARFDebugArangeSet, UnevenLength) {
"of the tuple size");
}
-TEST(DWARFDebugArangeSet, ZeroLengthEntry) {
+TEST(DWARFDebugArangeSet, ZeroAddressEntry) {
static const char DebugArangesSecRaw[] =
- "\x24\x00\x00\x00" // Length
+ "\x1c\x00\x00\x00" // Length
"\x02\x00" // Version
"\x00\x00\x00\x00" // Debug Info Offset
"\x04" // Address Size
@@ -176,14 +188,84 @@ TEST(DWARFDebugArangeSet, ZeroLengthEntry) {
"\x00\x00\x00\x00" // Padding
"\x00\x00\x00\x00" // Entry1: Address
"\x01\x00\x00\x00" // Length
+ "\x00\x00\x00\x00" // Termination tuple
+ "\x00\x00\x00\x00";
+ DWARFDataExtractor Extractor(
+ StringRef(DebugArangesSecRaw, sizeof(DebugArangesSecRaw) - 1),
+ /*IsLittleEndian=*/true,
+ /*AddressSize=*/4);
+ DWARFDebugArangeSet Set;
+ uint64_t Offset = 0;
+ ASSERT_THAT_ERROR(Set.extract(Extractor, &Offset, WarningHandler()),
+ Succeeded());
+ auto Range = Set.descriptors();
+ auto Iter = Range.begin();
+ ASSERT_EQ(std::distance(Iter, Range.end()), 1u);
+ EXPECT_EQ(Iter->Address, 0u);
+ EXPECT_EQ(Iter->Length, 1u);
+}
+
+TEST(DWARFDebugArangeSet, ZeroLengthEntry) {
+ static const char DebugArangesSecRaw[] =
+ "\x1c\x00\x00\x00" // Length
+ "\x02\x00" // Version
+ "\x00\x00\x00\x00" // Debug Info Offset
+ "\x04" // Address Size
+ "\x00" // Segment Selector Size
+ "\x00\x00\x00\x00" // Padding
+ "\x01\x00\x00\x00" // Entry1: Address
+ "\x00\x00\x00\x00" // Length
+ "\x00\x00\x00\x00" // Termination tuple
+ "\x00\x00\x00\x00";
+ DWARFDataExtractor Extractor(
+ StringRef(DebugArangesSecRaw, sizeof(DebugArangesSecRaw) - 1),
+ /*IsLittleEndian=*/true,
+ /*AddressSize=*/4);
+ DWARFDebugArangeSet Set;
+ uint64_t Offset = 0;
+ ASSERT_THAT_ERROR(Set.extract(Extractor, &Offset, WarningHandler()),
+ Succeeded());
+ auto Range = Set.descriptors();
+ auto Iter = Range.begin();
+ ASSERT_EQ(std::distance(Iter, Range.end()), 1u);
+ EXPECT_EQ(Iter->Address, 1u);
+ EXPECT_EQ(Iter->Length, 0u);
+}
+
+TEST(DWARFDebugArangesSet, PrematureTerminator) {
+ static const char DebugArangesSecRaw[] =
+ "\x24\x00\x00\x00" // Length
+ "\x02\x00" // Version
+ "\x00\x00\x00\x00" // Debug Info Offset
+ "\x04" // Address Size
+ "\x00" // Segment Selector Size
+ "\x00\x00\x00\x00" // Padding
+ "\x00\x00\x00\x00" // Entry1: Premature
+ "\x00\x00\x00\x00" // terminator
"\x01\x00\x00\x00" // Entry2: Address
- "\x00\x00\x00\x00" // Length (invalid)
+ "\x01\x00\x00\x00" // Length
"\x00\x00\x00\x00" // Termination tuple
"\x00\x00\x00\x00";
- ExpectExtractError(
- DebugArangesSecRaw,
- "address range table at offset 0x0 has an invalid tuple (length = 0) "
- "at offset 0x18");
+ DWARFDataExtractor Extractor(
+ StringRef(DebugArangesSecRaw, sizeof(DebugArangesSecRaw) - 1),
+ /*IsLittleEndian=*/true,
+ /*AddressSize=*/4);
+ DWARFDebugArangeSet Set;
+ uint64_t Offset = 0;
+ WarningHandler Warnings;
+ ASSERT_THAT_ERROR(Set.extract(Extractor, &Offset, Warnings), Succeeded());
+ auto Range = Set.descriptors();
+ auto Iter = Range.begin();
+ ASSERT_EQ(std::distance(Iter, Range.end()), 2u);
+ EXPECT_EQ(Iter->Address, 0u);
+ EXPECT_EQ(Iter->Length, 0u);
+ ++Iter;
+ EXPECT_EQ(Iter->Address, 1u);
+ EXPECT_EQ(Iter->Length, 1u);
+ EXPECT_THAT_ERROR(
+ Warnings.getWarning(),
+ FailedWithMessage("address range table at offset 0x0 has a premature "
+ "terminator entry at offset 0x10"));
}
} // end anonymous namespace
More information about the llvm-commits
mailing list