Repository: angr/angr

Issue:
Ternary expression optimizer may change control logic
### Description

Appears when "Transform ITE-assignment regions into ternary expression assignments" optimization is enabled. `break` statements will be removed.

Without 
```c
extern char hashes;

int authenticate(void* a0, void* a1)
{
    unsigned int v0;  // [bp-0x2c]
    char v1;  // [bp-0x28]
    unsigned int v3;  // eax

    if (memcmp(a0, "admin\n", 7))
    {
        v3 = 0;
    }
    else
    {
        MD5(&v1, a1, 100);
        v0 = 0;
        while (true)
        {
            if (v0 <= 15)
            {
                xor_(a1, &(&hashes)[16 * v0], 16);
                if (memcmp(&(&hashes)[16 * v0], &v1, 16))
                {
                    v0 += 1;
                }
                else
                {
                    puts("Authenticating...");
                    sleep(1);
                    puts("Authenticated!");
                    v3 = 1;
                    break;
                }
            }
            else if (!memcmp(a1, "Welcome to the admin console, trusted user!", 16))
            {
                v3 = 1;
                break;
            }
            else
            {
                v3 = 0;
                break;
            }
        }
    }
    return v3;
}
```

with:

```c
extern char hashes;

int authenticate(void* a0, void* a1)
{
    unsigned int v0;  // [bp-0x2c]
    char v1;  // [bp-0x28]
    unsigned int v3;  // eax

    if (memcmp(a0, "admin\n", 7))
    {
        v3 = 0;
    }
    else
    {
        MD5(&v1, a1, 100);
        v0 = 0;
        while (true)
        {
            if (v0 > 15)
            {
                v3 = (!memcmp(a1, "Welcome to the admin console, trusted user!", 16) ? 0 : 1);
            }
            else
            {
                xor_(a1, &(&hashes)[16 * v0], 16);
                if (memcmp(&(&hashes)[16 * v0], &v1, 16))
                {
                    v0 += 1;
                }
                else
                {
                    puts("Authenticating...");
                    sleep(1);
                    puts("Authenticated!");
                    v3 = 1;
                    break;
                }
            }
        }
    }
    return v3;
}
```

other optimization flags changed at time of writing:

![image](https://github.com/angr/angr/assets/8210/ac30b56b-d63b-412c-a4e8-017ae42273b0)


### Steps to reproduce the bug

[binary.zip](https://github.com/angr/angr/files/14951910/binary.zip)


### Environment

```
angr environment report
=============================
Date: 2024-04-11 15:19:50.244399
Running in virtual environment at /home/matt/.virtualenvs/angr-cp312
/home/matt/work/angr/angr-dev/angr/angr/misc/bug_report.py:88: DeprecationWarning: pkg_resources is deprecated as an API. See https://setuptools.pypa.io/en/latest/pkg_resources.html
  import pkg_resources  # pylint:disable=import-outside-toplevel
Platform: linux-x86_64
Python version: 3.12.0 (main, Oct 21 2023, 17:42:12) [GCC 11.4.0]
######## angr #########
Python found it in /home/matt/work/angr/angr-dev/angr/angr/__init__.py
Pip version angr 9.2.97.dev0
Git info:
	Current commit b0396c9fd3d72c0b1ab47fd0956654cef1366a60 from branch master
	Checked out from remote upstream: https://github.com/angr/angr.git
######## ailment #########
Python found it in /home/matt/work/angr/angr-dev/ailment/ailment/__init__.py
Pip version ailment 9.2.97.dev0
Git info:
	Current commit 169a0321d99a0d7ec76936c00fe605b2e436a1bd from branch master
	Checked out from remote origin: https://github.com/angr/ailment.git
######## cle #########
Python found it in /home/matt/work/angr/angr-dev/cle/cle/__init__.py
Pip version cle 9.2.97.dev0
Git info:
	Current commit 8f6ea207d1eb256bcb57664d4cfd23714c5a1a05 from branch fix/update-pyxbe2
Could not resolve tracking branch or remote info!
######## pyvex #########
Python found it in /home/matt/work/angr/angr-dev/pyvex/pyvex/__init__.py
Pip version pyvex 9.2.97.dev0
Git info:
	Current commit 47e4329014de718b08e9fc6fd4b71cf829f30399 from branch master
	Checked out from remote origin: https://github.com/angr/pyvex
######## claripy #########
Python found it in /home/matt/work/angr/angr-dev/claripy/claripy/__init__.py
Pip version claripy 9.2.97.dev0
Git info:
	Current commit fbb9b58aee92d0d49c7171838648fdc8597a2849 from branch master
	Checked out from remote origin: https://github.com/angr/claripy
######## archinfo #########
Python found it in /home/matt/work/angr/angr-dev/archinfo/archinfo/__init__.py
Pip version archinfo 9.2.97.dev0
Git info:
	Current commit ab22590c64cb52478e3c2681aa1e5227f500d23c from branch master
	Checked out from remote origin: https://github.com/angr/archinfo.git
######## z3 #########
Python found it in /home/matt/.virtualenvs/angr-cp312/lib/python3.12/site-packages/z3/__init__.py
Pip version z3-solver 4.10.2.0
Couldn't find git info
######## unicorn #########
Python found it in /home/matt/.virtualenvs/angr-cp312/lib/python3.12/site-packages/unicorn/__init__.py
Pip version unicorn 1.0.2
Couldn't find git info
######### Native Module Info ##########
angr: <CDLL '/home/matt/work/angr/angr-dev/angr/angr/state_plugins/../lib/angr_native.so', handle 2c20d60 at 0x7f6c979f0b90>
unicorn: <CDLL '/home/matt/.virtualenvs/angr-cp312/lib/python3.12/site-packages/unicorn/lib/libunicorn.so', handle 25fd040 at 0x7f6c9d4b3620>
pyvex: <cffi.api._make_ffi_library.<locals>.FFILibrary object at 0x7f6c9b6433b0>
z3: <CDLL '/home/matt/.virtualenvs/angr-cp312/lib/python3.12/site-packages/z3/lib/libz3.so', handle 2222600 at 0x7f6c9d648c20>
```

### Additional context

_No response_


Discussion:
I believe this and #4573 are linked. Both will be bugs inside Clinic propagation, possible the same one. 

Resolving patch:
diff --git a/angr/analyses/decompiler/optimization_passes/ite_region_converter.py b/angr/analyses/decompiler/optimization_passes/ite_region_converter.py
--- a/angr/analyses/decompiler/optimization_passes/ite_region_converter.py
+++ b/angr/analyses/decompiler/optimization_passes/ite_region_converter.py
@@ -2,7 +2,7 @@
 import logging
 
 from ailment.statement import ConditionalJump, Assignment, Jump
-from ailment.expression import ITE
+from ailment.expression import ITE, Const
 
 from ....utils.graph import subgraph_between_nodes
 from ..utils import remove_labels, to_ail_supergraph
@@ -146,10 +146,11 @@ def _convert_region_to_ternary_expr(self, region_head, region_tail, true_stmt, f
         #
 
         new_region_head = region_head.copy()
+        conditional_jump: ConditionalJump = region_head.statements[-1]
         addr_obj = true_stmt.src if "ins_addr" in true_stmt.src.tags else true_stmt
         ternary_expr = ITE(
             None,
-            region_head.statements[-1].condition,
+            conditional_jump.condition,
             true_stmt.src,
             false_stmt.src,
             ins_addr=addr_obj.ins_addr,
@@ -160,6 +161,13 @@ def _convert_region_to_ternary_expr(self, region_head, region_tail, true_stmt, f
         new_assignment.src = ternary_expr
         new_region_head.statements[-1] = new_assignment
 
+        # add a goto statement to the region tail so it can be transformed into a break or other types of control-flow
+        # transitioning statement in the future
+        goto_stmt = Jump(
+            None, Const(None, None, region_tail.addr, self.project.arch.bits), region_tail.idx, **conditional_jump.tags
+        )
+        new_region_head.statements.append(goto_stmt)
+
         #
         # destroy all the old region blocks
         #


Test patch:
diff --git a/tests/analyses/decompiler/test_decompiler.py b/tests/analyses/decompiler/test_decompiler.py
--- a/tests/analyses/decompiler/test_decompiler.py
+++ b/tests/analyses/decompiler/test_decompiler.py
@@ -26,6 +26,8 @@
     DUPLICATING_OPTS,
     LoweredSwitchSimplifier,
     InlinedStringTransformationSimplifier,
+    ReturnDuplicatorLow,
+    ReturnDuplicatorHigh,
 )
 from angr.analyses.decompiler.decompilation_options import get_structurer_option, PARAM_TO_OPTION
 from angr.analyses.decompiler.structuring import STRUCTURER_CLASSES
@@ -3489,6 +3491,26 @@ def test_simplifying_string_transformation_loops(self, decompiler_options=None):
         assert "wstrncpy(" in d.codegen.text
         assert "ObMakeTemporaryObject" in d.codegen.text
 
+    @structuring_algo("phoenix")
+    def test_ite_region_converter_missing_break_statement(self, decompiler_options=None):
+        # https://github.com/angr/angr/issues/4574
+        bin_path = os.path.join(test_location, "x86_64", "ite_region_converter_missing_breaks")
+        proj = angr.Project(bin_path, auto_load_libs=False)
+        cfg = proj.analyses.CFGFast(normalize=True, data_references=True)
+        f = proj.kb.functions["authenticate"]
+
+        # disable return duplicator
+        all_optimization_passes = angr.analyses.decompiler.optimization_passes.get_default_optimization_passes(
+            "AMD64", "linux", disable_opts={ReturnDuplicatorLow, ReturnDuplicatorHigh}
+        )
+
+        d = proj.analyses[Decompiler].prep()(
+            f, cfg=cfg.model, options=decompiler_options, optimization_passes=all_optimization_passes
+        )
+        self._print_decompilation_result(d)
+
+        assert d.codegen.text.count("break;") == 2
+
 
 if __name__ == "__main__":
     unittest.main()