Assertion `enum_ == Enum::Reference' failed at wasm-validate

Environment

OS      : Linux ubuntu 5.15.0-46-generic #49~20.04.1-Ubuntu SMP Thu Aug 4 19:15:44 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux
Commit  : 3054d61f703d609995798f872fc86b462617c294
Version : 1.0.29
Build   : make clang-debug-asan

Proof of concept

poc_wasm-validate.wasm
poc_wasm-validate.wasm.zip

Stack dump

$ ./wasm-validate --enable-all poc_wasm-validate.wasm
wasm-validate: ../../../../src/type.h:132: wabt::Index wabt::Type::GetReferenceIndex() const: Assertion `enum_ == Enum::Reference' failed.
Aborted

$ gdb  ./wasm-validate
pwndbg> r --enable-all ./8858c8fd6729859-id\:000000\,sig\:06\,src\:000000\,time\:152726\,execs\:15118\,op\:havoc\,rep\:4.wasm
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
wasm-validate: ../../../../src/type.h:132: wabt::Index wabt::Type::GetReferenceIndex() const: Assertion `enum_ == Enum::Reference' failed.

Program received signal SIGABRT, Aborted.
__GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
50	../sysdeps/unix/sysv/linux/raise.c: No such file or directory.
LEGEND: STACK | HEAP | CODE | DATA | RWX | RODATA
─────────────────────────────────────────────────────────────────────────────────[ REGISTERS ]──────────────────────────────────────────────────────────────────────────────────
 RAX  0x0
 RBX  0x7ffff7a357c0 ◂— 0x7ffff7a357c0
 RCX  0x7ffff7a7b00b (raise+203) —▸ 0x10824848b48 ◂— 0x0
 RDX  0x0
 RDI  0x2
 RSI  0x7fffffff8c30 ◂— 0x0
 R8   0x0
 R9   0x7fffffff8c30 ◂— 0x0
 R10  0x8
 R11  0x246
 R12  0x785a80 (str) ◂— '../../../../src/type.h'
 R13  0x84
 R14  0x785a40 (str) ◂— 'enum_ == Enum::Reference'
 R15  0x0
 RBP  0x7ffff7bf0588 ◂— "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n"
 RSP  0x7fffffff8c30 ◂— 0x0
 RIP  0x7ffff7a7b00b (raise+203) —▸ 0x10824848b48 ◂— 0x0
───────────────────────────────────────────────────────────────────────────────────[ DISASM ]───────────────────────────────────────────────────────────────────────────────────
 ► 0x7ffff7a7b00b <raise+203>    mov    rax, qword ptr [rsp + 0x108]
   0x7ffff7a7b013 <raise+211>    xor    rax, qword ptr fs:[0x28]
   0x7ffff7a7b01c <raise+220>    jne    raise+260                <raise+260>
    ↓
   0x7ffff7a7b044 <raise+260>    call   __stack_chk_fail                <__stack_chk_fail>

   0x7ffff7a7b049                nop    dword ptr [rax]
   0x7ffff7a7b050 <killpg>       endbr64
   0x7ffff7a7b054 <killpg+4>     test   edi, edi
   0x7ffff7a7b056 <killpg+6>     js     killpg+16                <killpg+16>

   0x7ffff7a7b058 <killpg+8>     neg    edi
   0x7ffff7a7b05a <killpg+10>    jmp    kill                <kill>

   0x7ffff7a7b05f <killpg+15>    nop
───────────────────────────────────────────────────────────────────────────────────[ STACK ]────────────────────────────────────────────────────────────────────────────────────
00:0000│ rsi r9 rsp 0x7fffffff8c30 ◂— 0x0
01:0008│            0x7fffffff8c38 —▸ 0x4ba4d0 (free) ◂— push   rbp
02:0010│            0x7fffffff8c40 ◂— 0x7ffffbad8000
03:0018│            0x7fffffff8c48 —▸ 0x612000000340 ◂— 0xc800001
04:0020│            0x7fffffff8c50 —▸ 0x6120000003a5 ◂— "on `enum_ == Enum::Reference' failed.\n"
05:0028│            0x7fffffff8c58 —▸ 0x612000000340 ◂— 0xc800001
06:0030│            0x7fffffff8c60 —▸ 0x612000000340 ◂— 0xc800001
07:0038│            0x7fffffff8c68 —▸ 0x6120000003cb ◂— 0x0
─────────────────────────────────────────────────────────────────────────────────[ BACKTRACE ]──────────────────────────────────────────────────────────────────────────────────
 ► f 0   0x7ffff7a7b00b raise+203
   f 1   0x7ffff7a5a859 abort+299
   f 2   0x7ffff7a5a729 _nl_load_domain.cold
   f 3   0x7ffff7a6bfd6
   f 4         0x7238c8
   f 5         0x715885
   f 6         0x6d93dd
   f 7         0x5f912d
────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────────
pwndbg> bt
#0  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
#1  0x00007ffff7a5a859 in __GI_abort () at abort.c:79
#2  0x00007ffff7a5a729 in __assert_fail_base (fmt=0x7ffff7bf0588 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=0x785a40 <str> "enum_ == Enum::Reference", file=0x785a80 <str> "../../../../src/type.h", line=132, function=<optimized out>) at assert.c:92
#3  0x00007ffff7a6bfd6 in __GI___assert_fail (assertion=0x785a40 <str> "enum_ == Enum::Reference", file=0x785a80 <str> "../../../../src/type.h", line=132, function=0x785ac0 <__PRETTY_FUNCTION__._ZNK4wabt4Type17GetReferenceIndexEv> "wabt::Index wabt::Type::GetReferenceIndex() const") at assert.c:101
#4  0x00000000007238c8 in wabt::Type::GetReferenceIndex (this=0x7fffffff8f70) at ../../../../src/type.h:132
#5  0x0000000000715885 in wabt::TypeChecker::OnIndexedFuncRef (this=0x7fffffffd568, out_index=0x7fffffff9200) at ../../../../src/type-checker.cc:536
#6  0x00000000006d93dd in wabt::SharedValidator::OnCallRef (this=0x7fffffffd548, loc=..., function_type_index=0x7fffffff94b0) at ../../../../src/shared-validator.cc:706
#7  0x00000000005f912d in wabt::(anonymous namespace)::Validator::OnCallRefExpr (this=0x7fffffffd530, expr=0x60d000000380) at ../../../../src/validator.cc:281
#8  0x00000000006a82ba in wabt::ExprVisitor::HandleDefaultState (this=0x7fffffffc0f0, expr=0x60d000000380) at ../../../../src/expr-visitor.cc:219
#9  0x00000000006a408e in wabt::ExprVisitor::VisitExpr (this=0x7fffffffc0f0, root_expr=0x60d000000380) at ../../../../src/expr-visitor.cc:41
#10 0x00000000006adc5f in wabt::ExprVisitor::VisitExprList (this=0x7fffffffc0f0, exprs=...) at ../../../../src/expr-visitor.cc:148
#11 0x00000000005f33a8 in wabt::(anonymous namespace)::Validator::CheckModule (this=0x7fffffffd530) at ../../../../src/validator.cc:830
#12 0x00000000005ed6de in wabt::ValidateModule (module=0x7fffffffda10, errors=0x7fffffffd9d0, options=...) at ../../../../src/validator.cc:1044
#13 0x00000000004efb42 in ProgramMain (argc=3, argv=0x7fffffffe178) at ../../../../src/tools/wasm-validate.cc:88
#14 0x00000000004f01a2 in main (argc=3, argv=0x7fffffffe178) at ../../../../src/tools/wasm-validate.cc:97
#15 0x00007ffff7a5c083 in __libc_start_main (main=0x4f0180 <main(int, char**)>, argc=3, argv=0x7fffffffe178, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fffffffe168) at ../csu/libc-start.c:308
#16 0x000000000043e00e in _start ()

Start with the wasm-validate entry point in src/tools/wasm-validate.cc and follow the reported path through src/validator.cc, src/shared-validator.cc, src/type-checker.cc, and src/type.h. Run wasm-validate --enable-all on the supplied poc_wasm-validate.wasm; done means the input no longer aborts on the reported assertion and is handled as validation output.