[llvm] 23cf0a3 - [DebugInfo] Add check for zero debug line opcode_base
James Henderson via llvm-commits
llvm-commits at lists.llvm.org
Wed Feb 12 06:49:46 PST 2020
Author: James Henderson
Date: 2020-02-12T14:49:22Z
New Revision: 23cf0a30b1528cf268ffdf13e04a5baa7eddfe0a
URL: https://github.com/llvm/llvm-project/commit/23cf0a30b1528cf268ffdf13e04a5baa7eddfe0a
DIFF: https://github.com/llvm/llvm-project/commit/23cf0a30b1528cf268ffdf13e04a5baa7eddfe0a.diff
LOG: [DebugInfo] Add check for zero debug line opcode_base
The number of standard opcodes is defined to be opcode_base - 1, so a
value of 0 for the opcode_base caused a crash as an attempt was made to
reserve many entries in a vector. This change fixes the crash, by
issuing a warning and skipping reading of standard opcode lengths in the
event of an opcode_base of 0.
Reviewed by: dblaikie
Differential Revision: https://reviews.llvm.org/D74309
Added:
Modified:
llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp
llvm/test/tools/llvm-dwarfdump/X86/Inputs/debug_line_malformed.s
llvm/test/tools/llvm-dwarfdump/X86/debug_line_invalid.test
Removed:
################################################################################
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp b/llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp
index 2b4c492b4544..2c869dfdd243 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFDebugLine.cpp
@@ -356,10 +356,21 @@ Error DWARFDebugLine::Prologue::parse(
LineRange = DebugLineData.getU8(OffsetPtr);
OpcodeBase = DebugLineData.getU8(OffsetPtr);
- StandardOpcodeLengths.reserve(OpcodeBase - 1);
- for (uint32_t I = 1; I < OpcodeBase; ++I) {
- uint8_t OpLen = DebugLineData.getU8(OffsetPtr);
- StandardOpcodeLengths.push_back(OpLen);
+ if (OpcodeBase == 0) {
+ // If the opcode base is 0, we cannot read the standard opcode lengths (of
+ // which there are supposed to be one fewer than the opcode base). Assume
+ // there are no standard opcodes and continue parsing.
+ RecoverableErrorHandler(createStringError(
+ errc::invalid_argument,
+ "parsing line table prologue at offset 0x%8.8" PRIx64
+ " found opcode base of 0. Assuming no standard opcodes",
+ PrologueOffset));
+ } else {
+ StandardOpcodeLengths.reserve(OpcodeBase - 1);
+ for (uint32_t I = 1; I < OpcodeBase; ++I) {
+ uint8_t OpLen = DebugLineData.getU8(OffsetPtr);
+ StandardOpcodeLengths.push_back(OpLen);
+ }
}
if (getVersion() >= 5) {
diff --git a/llvm/test/tools/llvm-dwarfdump/X86/Inputs/debug_line_malformed.s b/llvm/test/tools/llvm-dwarfdump/X86/Inputs/debug_line_malformed.s
index e01ed9a5bfae..0477a668d5a7 100644
--- a/llvm/test/tools/llvm-dwarfdump/X86/Inputs/debug_line_malformed.s
+++ b/llvm/test/tools/llvm-dwarfdump/X86/Inputs/debug_line_malformed.s
@@ -423,6 +423,30 @@
.byte 0, 1, 1 # DW_LNE_end_sequence
.Linvalid_dir_form_end0:
+# Zero opcode base.
+.long .Lzero_opcode_base_end - .Lzero_opcode_base_start # unit length
+.Lzero_opcode_base_start:
+.short 4 # version
+.long .Lzero_opcode_base_prologue_end-.Lzero_opcode_base_prologue_start # Length of Prologue
+.Lzero_opcode_base_prologue_start:
+.byte 1 # Minimum Instruction Length
+.byte 1 # Maximum Operations per Instruction
+.byte 1 # Default is_stmt
+.byte 0 # Line Base
+.byte 1 # Line Range
+.byte 0 # Opcode Base
+.asciz "dir1" # Include table
+.byte 0
+.asciz "file1"
+.byte 1, 2, 3
+.byte 0
+.Lzero_opcode_base_prologue_end:
+.byte 0, 9, 2 # DW_LNE_set_address
+.quad 0xffffeeeeddddcccc
+.byte 0x1 # Special opcode
+.byte 0, 1, 1 # DW_LNE_end_sequence
+.Lzero_opcode_base_end:
+
# Trailing good section.
.long .Lunit_good_end - .Lunit_good_start # Length of Unit (DWARF-32 format)
.Lunit_good_start:
diff --git a/llvm/test/tools/llvm-dwarfdump/X86/debug_line_invalid.test b/llvm/test/tools/llvm-dwarfdump/X86/debug_line_invalid.test
index 60a15b49496c..d4b504592cfd 100644
--- a/llvm/test/tools/llvm-dwarfdump/X86/debug_line_invalid.test
+++ b/llvm/test/tools/llvm-dwarfdump/X86/debug_line_invalid.test
@@ -36,7 +36,7 @@
# RUN: FileCheck %s --input-file=%t-malformed-off-first.err --check-prefix=ALL
## Don't stop looking for the later unit if non-fatal issues are found.
-# RUN: llvm-dwarfdump -debug-line=0x332 %t-malformed.o 2> %t-malformed-off-last.err \
+# RUN: llvm-dwarfdump -debug-line=0x361 %t-malformed.o 2> %t-malformed-off-last.err \
# RUN: | FileCheck %s --check-prefix=LAST --implicit-check-not='debug_line[{{.*}}]'
# RUN: FileCheck %s --input-file=%t-malformed-off-last.err --check-prefix=ALL
@@ -159,7 +159,19 @@
# NONFATAL-NOT: file_names
# NONFATAL: 0xaaaabbbbccccdddd {{.*}} is_stmt end_sequence
-# LAST: debug_line[0x00000332]
+## Opcode base field of value zero.
+# NONFATAL: debug_line[0x00000332]
+# NONFATAL-NEXT: Line table prologue
+# NONFATAL: include_directories[ 1] = "dir1"
+# NONFATAL-NEXT: file_names[ 1]:
+# NONFATAL-NEXT: name: "file1"
+# NONFATAL-NEXT: dir_index: 1
+# NONFATAL-NEXT: mod_time: 0x00000002
+# NONFATAL-NEXT: length: 0x00000003
+# NONFATAL: 0xffffeeeeddddcccd 1 0 1 0 0 is_stmt{{$}}
+# NONFATAL: 0xffffeeeeddddcccd 1 0 1 0 0 is_stmt end_sequence{{$}}
+
+# LAST: debug_line[0x00000361]
# LAST: 0x00000000cafebabe {{.*}} end_sequence
# RESERVED: warning: parsing line table prologue at offset 0x00000048 unsupported reserved unit length found of value 0xfffffffe
@@ -184,4 +196,5 @@
# ALL-NEXT: warning: parsing line table prologue at 0x000002ae should have ended at 0x000002d9 but it ended at 0x000002e0
# ALL-NEXT: warning: parsing line table prologue at 0x000002ec found an invalid directory or file table description at 0x00000315
# ALL-NEXT: warning: failed to parse directory entry because skipping the form value failed.
+# ALL-NEXT: warning: parsing line table prologue at offset 0x00000332 found opcode base of 0. Assuming no standard opcodes
# ALL-NOT: warning:
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