The signed integer overflow occurred when adding one to target_count
for (i = 0; i < target_count + 1; i++)
but that's the least of the worries here. target_count was long and i
int, leading to the possibility of a loop that never ended.
So to avoid this type of vulnerability, this patch uses what I believe
to be the proper types for arguments of various wasm32 opcodes, rather
than using "long" which may change in size.
gas/
* testsuite/gas/wasm32/allinsn.d: Update expected output.
opcodes/
* wasm32-dis.c (print_insn_wasm32): Localise variables. Store
result of wasm_read_leb128 in a uint64_t and check that bits
are not lost when copying to other locals. Use uint32_t for
most locals. Use PRId64 when printing int64_t.
Remove `-Wshadow' compilation errors:
cc1: warnings being treated as errors
.../bfd/wasm-module.c: In function 'wasm_scan_name_function_section':
.../bfd/wasm-module.c:312: error: declaration of 'index' shadows a global declaration
/usr/include/string.h:303: error: shadowed declaration is here
.../bfd/wasm-module.c: In function 'wasm_register_section':
.../bfd/wasm-module.c:494: error: declaration of 'index' shadows a global declaration
/usr/include/string.h:303: error: shadowed declaration is here
.../bfd/wasm-module.c: In function 'wasm_compute_custom_section_file_position':
.../bfd/wasm-module.c:523: error: declaration of 'index' shadows a global declaration
/usr/include/string.h:303: error: shadowed declaration is here
and:
cc1: warnings being treated as errors
.../opcodes/wasm32-dis.c: In function 'print_insn_wasm32':
.../opcodes/wasm32-dis.c:272: error: declaration of 'index' shadows a global declaration
/usr/include/string.h:303: error: shadowed declaration is here
make[4]: *** [wasm32-dis.lo] Error 1
which for versions of GCC before 4.8 prevent support for the WebAssembly
target from being built. See also GCC PR c/53066.
bfd/
* wasm-module.c (wasm_scan_name_function_section): Rename
`index' local variable to `idx'.
opcodes/
* wasm32-dis.c (print_insn_wasm32): Rename `index' local
variable to `function_index'.
include * dis-asm.h: Add prototypes for wasm32 disassembler.
opcodes * Makefile.am: Add wasm32-dis.c.
* configure.ac: Add wasm32-dis.c to wasm32 target.
* disassemble.c: Add wasm32 disassembler code.
* wasm32-dis.c: New file.
* Makefile.in: Regenerate.
* configure: Regenerate.
* po/POTFILES.in: Regenerate.
* po/opcodes.pot: Regenerate.
gas * testsuite/gas/wasm32/allinsn.d: Adjust test for disassembler
changes.
* testsuite/gas/wasm32/disass.d: New test.
* testsuite/gas/wasm32/disass.s: New test.
* testsuite/gas/wasm32/disass-2.d: New test.
* testsuite/gas/wasm32/disass-2.s: New test.
* testsuite/gas/wasm32/reloc.d: Adjust test for changed reloc
names.
* testsuite/gas/wasm32/reloc.s: Update test for changed assembler
syntax.
* testsuite/gas/wasm32/wasm32.exp: Run new tests. Expect allinsn
test to succeed.