From 97ba6ca0d29c1e8a5b30112f13f37a4d6b3c4492 Mon Sep 17 00:00:00 2001
From: Inada Naoki <songofacandy@gmail.com>
Date: Wed, 3 Jun 2026 22:17:26 +0900
Subject: [PATCH 01/13] skip ci: remove unneeded CIBW_SKIP option

---
 .github/workflows/wheel.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/wheel.yml b/.github/workflows/wheel.yml
index fb78688..56b31f0 100644
--- a/.github/workflows/wheel.yml
+++ b/.github/workflows/wheel.yml
@@ -48,7 +48,7 @@ jobs:
         env:
           CIBW_TEST_REQUIRES: "pytest"
           CIBW_TEST_COMMAND: "pytest {package}/test"
-          CIBW_SKIP: "pp* cp38-* cp39-* cp310-win_arm64"
+          CIBW_SKIP: "cp38-* cp39-* cp310-win_arm64"
           CIBW_ARCHS: ${{ matrix.cibw_archs || 'auto' }}
 
       - name: Build sdist

From c410a388c58d55091736e510cad064977a12cb8b Mon Sep 17 00:00:00 2001
From: "dependabot[bot]" <49699333+dependabot[bot]@users.noreply.github.com>
Date: Thu, 11 Jun 2026 11:54:05 +0900
Subject: [PATCH 02/13] Bump pypa/cibuildwheel from 3.4.1 to 4.0.0 (#691)

---
 .github/workflows/wheel.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/wheel.yml b/.github/workflows/wheel.yml
index 56b31f0..a3d80b5 100644
--- a/.github/workflows/wheel.yml
+++ b/.github/workflows/wheel.yml
@@ -44,7 +44,7 @@ jobs:
           platforms: ${{ matrix.cibw_archs }}
 
       - name: Build
-        uses: pypa/cibuildwheel@8d2b08b68458a16aeb24b64e68a09ab1c8e82084 # v3.4.1
+        uses: pypa/cibuildwheel@f03ac7617d6cff873ccf24cc0d567ef5ba5a9e6d # v4.0.0
         env:
           CIBW_TEST_REQUIRES: "pytest"
           CIBW_TEST_COMMAND: "pytest {package}/test"

From 11ed0a5110c1920b85b7d24d9414f480983e0f16 Mon Sep 17 00:00:00 2001
From: Inada Naoki <songofacandy@gmail.com>
Date: Thu, 11 Jun 2026 12:29:41 +0900
Subject: [PATCH 03/13] release v1.2.0 (#692)

---
 CHANGELOG.md        | 2 +-
 msgpack/__init__.py | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 63cfcce..a29b4b2 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,6 @@
 # 1.2.0
 
-Release Date: TBD
+Release Date: 2026-06-11
 
 - Support free threaded Python. #654, #686
 - Dropped support for Python 3.9. #656
diff --git a/msgpack/__init__.py b/msgpack/__init__.py
index f7346d0..f053abd 100644
--- a/msgpack/__init__.py
+++ b/msgpack/__init__.py
@@ -5,7 +5,7 @@ from .exceptions import *  # noqa: F403
 from .ext import ExtType, Timestamp
 
 version = (1, 2, 0)
-__version__ = "1.2.0rc1"
+__version__ = "1.2.0"
 
 
 if os.environ.get("MSGPACK_PUREPYTHON"):

From 0f4f350b6f3e80f24750422673424cce5d96e15d Mon Sep 17 00:00:00 2001
From: "dependabot[bot]" <49699333+dependabot[bot]@users.noreply.github.com>
Date: Tue, 16 Jun 2026 13:22:58 +0900
Subject: [PATCH 04/13] Bump pypa/cibuildwheel from 4.0.0 to 4.1.0 in the
 all-dependencies group (#694)

---
 .github/workflows/wheel.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.github/workflows/wheel.yml b/.github/workflows/wheel.yml
index a3d80b5..92fce01 100644
--- a/.github/workflows/wheel.yml
+++ b/.github/workflows/wheel.yml
@@ -44,7 +44,7 @@ jobs:
           platforms: ${{ matrix.cibw_archs }}
 
       - name: Build
-        uses: pypa/cibuildwheel@f03ac7617d6cff873ccf24cc0d567ef5ba5a9e6d # v4.0.0
+        uses: pypa/cibuildwheel@294735312765b09d24a2fbec22660ce817587d55 # v4.1.0
         env:
           CIBW_TEST_REQUIRES: "pytest"
           CIBW_TEST_COMMAND: "pytest {package}/test"

From 2c56ddb5d0025ed481d962c0f5d62d19dec7476d Mon Sep 17 00:00:00 2001
From: Inada Naoki <songofacandy@gmail.com>
Date: Fri, 19 Jun 2026 00:13:13 +0900
Subject: [PATCH 05/13] Merge commit from fork

* fix Unpacker crash after unpack failure.

* fixup
---
 msgpack/_unpacker.pyx     |  8 ++++++--
 msgpack/unpack_template.h | 22 +++++++++++++++-------
 requirements.txt          |  3 ++-
 test/test_except.py       | 26 ++++++++++++++++++++++++++
 4 files changed, 49 insertions(+), 10 deletions(-)

diff --git a/msgpack/_unpacker.pyx b/msgpack/_unpacker.pyx
index 4bfbe06..e0cdde4 100644
--- a/msgpack/_unpacker.pyx
+++ b/msgpack/_unpacker.pyx
@@ -51,6 +51,7 @@ cdef extern from "unpack.h":
     execute_fn unpack_skip
     execute_fn read_array_header
     execute_fn read_map_header
+
     void unpack_init(unpack_context* ctx)
     object unpack_data(unpack_context* ctx)
     void unpack_clear(unpack_context* ctx)
@@ -197,6 +198,7 @@ def unpackb(object packed, *, object object_hook=None, object list_hook=None,
         if off < buf_len:
             raise ExtraData(obj, PyBytes_FromStringAndSize(buf+off, buf_len-off))
         return obj
+
     unpack_clear(&ctx)
     if ret == 0:
         raise ValueError("Unpack failed: incomplete input")
@@ -475,7 +477,7 @@ cdef class Unpacker:
                 obj = unpack_data(&self.ctx)
                 unpack_init(&self.ctx)
                 return obj
-            elif ret == 0:
+            if ret == 0:
                 if self.file_like is not None:
                     self.read_from_file()
                     continue
@@ -483,7 +485,9 @@ cdef class Unpacker:
                     raise StopIteration("No more data to unpack.")
                 else:
                     raise OutOfData("No more data to unpack.")
-            elif ret == -2:
+
+            unpack_clear(&self.ctx)
+            if ret == -2:
                 raise FormatError
             elif ret == -3:
                 raise StackError
diff --git a/msgpack/unpack_template.h b/msgpack/unpack_template.h
index 4230661..ab5887a 100644
--- a/msgpack/unpack_template.h
+++ b/msgpack/unpack_template.h
@@ -72,15 +72,14 @@ static inline PyObject* unpack_data(unpack_context* ctx)
 
 static inline void unpack_clear(unpack_context *ctx)
 {
-    unsigned int i;
-    for (i = 1; i < ctx->top; i++) {
-        Py_CLEAR(ctx->stack[i].obj);
+    for (unsigned int i = 0; i < ctx->top; i++) {
         /* map_key holds a live reference only while waiting for the value */
         if (ctx->stack[i].ct == CT_MAP_VALUE) {
             Py_CLEAR(ctx->stack[i].map_key);
         }
+        Py_CLEAR(ctx->stack[i].obj);
     }
-    Py_CLEAR(ctx->stack[0].obj);
+    unpack_init(ctx);
 }
 
 static inline int unpack_execute(bool construct, unpack_context* ctx, const char* data, Py_ssize_t len, Py_ssize_t* off)
@@ -200,7 +199,7 @@ static inline int unpack_execute(bool construct, unpack_context* ctx, const char
                 case 0xd5:  // fixext 2
                 case 0xd6:  // fixext 4
                 case 0xd7:  // fixext 8
-                    again_fixed_trail_if_zero(ACS_EXT_VALUE, 
+                    again_fixed_trail_if_zero(ACS_EXT_VALUE,
                                               (1 << (((unsigned int)*p) & 0x03))+1,
                                               _ext_zero);
                 case 0xd8:  // fixext 16
@@ -344,6 +343,7 @@ _push:
         goto _header_again;
     case CT_MAP_VALUE:
         if(construct_cb(_map_item)(user, c->count, &c->obj, c->map_key, obj) < 0) { goto _failed; }
+        c->map_key = NULL;
         if(++c->count == c->size) {
             obj = c->obj;
             if (construct_cb(_map_end)(user, &obj) < 0) { goto _failed; }
@@ -406,10 +406,18 @@ _end:
 #undef start_container
 
 static int unpack_construct(unpack_context *ctx, const char *data, Py_ssize_t len, Py_ssize_t *off) {
-    return unpack_execute(1, ctx, data, len, off);
+    int ret = unpack_execute(1, ctx, data, len, off);
+    if (ret == -1) {
+        unpack_clear(ctx);
+    }
+    return ret;
 }
 static int unpack_skip(unpack_context *ctx, const char *data, Py_ssize_t len, Py_ssize_t *off) {
-    return unpack_execute(0, ctx, data, len, off);
+    int ret = unpack_execute(0, ctx, data, len, off);
+    if (ret == -1) {
+        unpack_clear(ctx);
+    }
+    return ret;
 }
 
 #define unpack_container_header read_array_header
diff --git a/requirements.txt b/requirements.txt
index 9e4643b..7991e3f 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,3 +1,4 @@
-Cython==3.2.1
+cython==3.2.5
 setuptools==78.1.1
+pytest
 build
diff --git a/test/test_except.py b/test/test_except.py
index c04b110..a3bf467 100644
--- a/test/test_except.py
+++ b/test/test_except.py
@@ -33,6 +33,22 @@ def test_raise_from_object_hook():
         object_pairs_hook=hook,
     )
 
+    up = Unpacker(object_hook=hook)
+
+    def up_unpack(x):
+        up.feed(x)
+        return up.unpack()
+
+    raises(DummyException, up_unpack, packb({}))
+    raises(DummyException, up_unpack, packb({"fizz": "buzz"}))
+    raises(DummyException, up_unpack, packb({"fizz": "buzz"}))
+    raises(DummyException, up_unpack, packb({"fizz": {"buzz": "spam"}}))
+    raises(
+        DummyException,
+        up_unpack,
+        packb({"fizz": {"buzz": "spam"}}),
+    )
+
 
 def test_raise_from_list_hook():
     def hook(lst: list) -> list:
@@ -138,3 +154,13 @@ def test_strict_map_key_with_object_pairs_hook():
     packed = packb(valid, use_bin_type=True)
     result = unpackb(packed, raw=False, strict_map_key=True, object_pairs_hook=list)
     assert result == [("key", "value")]
+
+
+def test_unpacker_should_not_crash_after_exception():
+    up = Unpacker()  # default: strict_map_key=True
+    up.feed(b"\x83\x73\xc4\x00")  # fixmap(3): int key (rejected) + empty bin8
+    try:
+        up.unpack()  # ValueError: int is not allowed for map key ...
+    except Exception:
+        pass
+    up.skip()  # SIGSEGV (resumes from a corrupt parser context)

From 448d43f5dcca7b3a2b0810e161af0a6431d90071 Mon Sep 17 00:00:00 2001
From: Inada Naoki <songofacandy@gmail.com>
Date: Fri, 19 Jun 2026 00:33:29 +0900
Subject: [PATCH 06/13] release v1.2.1 (#698)

Co-authored-by: Copilot Autofix powered by AI <175728472+Copilot@users.noreply.github.com>
---
 CHANGELOG.md        | 9 +++++++++
 README.md           | 6 +++++-
 msgpack/__init__.py | 4 ++--
 3 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index a29b4b2..b8fbd8c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,12 @@
+# 1.2.1
+
+Release Date: 2026-06-19
+
+Fix a segfault when calling `Unpacker.unpack()` or `Unpacker.skip()` after an unpacking failure.
+But note that reusing the same `Unpacker` instance after an unpacking failure is not supported.
+Please create a new `Unpacker` instance instead. GHSA-6v7p-g79w-8964
+
+
 # 1.2.0
 
 Release Date: 2026-06-11
diff --git a/README.md b/README.md
index 223742d..e66d454 100644
--- a/README.md
+++ b/README.md
@@ -72,6 +72,10 @@ for unpacked in unpacker:
     print(unpacked)
 ```
 
+> [!IMPORTANT]
+> If `Unpacker.unpack()` stops with an exception other than `OutOfData`, that `Unpacker` cannot be reused.
+> Create a new `Unpacker` when reading another stream.
+
 
 ### Packing/unpacking of custom data types
 
@@ -220,7 +224,7 @@ When upgrading from msgpack-0.4 or earlier, do `pip uninstall msgpack-python` be
 
   * The extension module no longer supports Python 2.
     The pure Python implementation (`msgpack.fallback`) is used for Python 2.
-  
+
   * msgpack 1.0.6 drops official support of Python 2.7, as pip and
     GitHub Action "setup-python" no longer supports Python 2.7.
 
diff --git a/msgpack/__init__.py b/msgpack/__init__.py
index f053abd..eeb85af 100644
--- a/msgpack/__init__.py
+++ b/msgpack/__init__.py
@@ -4,8 +4,8 @@ import os
 from .exceptions import *  # noqa: F403
 from .ext import ExtType, Timestamp
 
-version = (1, 2, 0)
-__version__ = "1.2.0"
+version = (1, 2, 1)
+__version__ = "1.2.1"
 
 
 if os.environ.get("MSGPACK_PUREPYTHON"):

From f1a170234a95dd64d4c0dee398d16d4a011e90ea Mon Sep 17 00:00:00 2001
From: Inada Naoki <songofacandy@gmail.com>
Date: Fri, 19 Jun 2026 18:49:02 +0900
Subject: [PATCH 07/13] fix docstring for read_size (#700)

fix #697
---
 .gitignore            | 1 +
 msgpack/_unpacker.pyx | 2 +-
 msgpack/fallback.py   | 2 +-
 3 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/.gitignore b/.gitignore
index 341be63..31d7d6e 100644
--- a/.gitignore
+++ b/.gitignore
@@ -15,3 +15,4 @@ msgpack/*.cpp
 /tags
 /docs/_build
 .cache
+uv.lock
diff --git a/msgpack/_unpacker.pyx b/msgpack/_unpacker.pyx
index e0cdde4..26fb377 100644
--- a/msgpack/_unpacker.pyx
+++ b/msgpack/_unpacker.pyx
@@ -222,7 +222,7 @@ cdef class Unpacker:
         If specified, unpacker reads serialized data from it and `.feed()` is not usable.
 
     :param int read_size:
-        Used as `file_like.read(read_size)`. (default: `min(16*1024, max_buffer_size)`)
+        Used as `file_like.read(read_size)`. Must be equal to or smaller than *max_buffer_size*.
 
     :param bool use_list:
         If true, unpack msgpack array to Python list.
diff --git a/msgpack/fallback.py b/msgpack/fallback.py
index 860d94a..824f59d 100644
--- a/msgpack/fallback.py
+++ b/msgpack/fallback.py
@@ -137,7 +137,7 @@ class Unpacker:
         If specified, unpacker reads serialized data from it and `.feed()` is not usable.
 
     :param int read_size:
-        Used as `file_like.read(read_size)`. (default: `min(16*1024, max_buffer_size)`)
+        Used as `file_like.read(read_size)`. Must be equal to or smaller than *max_buffer_size*.
 
     :param bool use_list:
         If true, unpack msgpack array to Python list.

From d13418061d00e10964394bda555247727f85ce28 Mon Sep 17 00:00:00 2001
From: Inada Naoki <songofacandy@gmail.com>
Date: Fri, 19 Jun 2026 20:48:27 +0900
Subject: [PATCH 08/13] unpacker: fix silent datetime truncation with
 datetime=3 (#701)

---
 msgpack/unpack.h       | 9 ++++++++-
 test/test_timestamp.py | 6 ++++++
 2 files changed, 14 insertions(+), 1 deletion(-)

diff --git a/msgpack/unpack.h b/msgpack/unpack.h
index 0f9ffc0..55cfdab 100644
--- a/msgpack/unpack.h
+++ b/msgpack/unpack.h
@@ -283,6 +283,7 @@ static int unpack_timestamp(const char* buf, unsigned int buflen, msgpack_timest
         ts->tv_sec = _msgpack_load64(int64_t, buf + 4);
         return 0;
     default:
+        PyErr_Format(PyExc_ValueError, "invalid timestamp data (length %u)", buflen);
         return -1;
     }
 }
@@ -336,12 +337,18 @@ static int unpack_callback_ext(unpack_user* u, const char* base, const char* pos
         else if (u->timestamp == 3) {  // datetime
             // Calculate datetime using epoch + delta
             // due to limitations PyDateTime_FromTimestamp on Windows with negative timestamps
+            int64_t days = ts.tv_sec / (24*3600);
+            if (days < INT_MIN || days > INT_MAX) {
+                PyErr_Format(PyExc_OverflowError,
+                            "days=%lld; too large to convert to C int", days);
+                return -1;
+            }
             PyObject *epoch = PyDateTimeAPI->DateTime_FromDateAndTime(1970, 1, 1, 0, 0, 0, 0, u->utc, PyDateTimeAPI->DateTimeType);
             if (epoch == NULL) {
                 return -1;
             }
 
-            PyObject* d = PyDelta_FromDSU(ts.tv_sec/(24*3600), ts.tv_sec%(24*3600), ts.tv_nsec / 1000);
+            PyObject* d = PyDelta_FromDSU((int)days, ts.tv_sec%(24*3600), ts.tv_nsec / 1000);
             if (d == NULL) {
                 Py_DECREF(epoch);
                 return -1;
diff --git a/test/test_timestamp.py b/test/test_timestamp.py
index 6dfe368..7c8e3e8 100644
--- a/test/test_timestamp.py
+++ b/test/test_timestamp.py
@@ -176,3 +176,9 @@ def test_pack_datetime_without_tzinfo():
     packed = msgpack.packb(dt, datetime=True)
     unpacked = msgpack.unpackb(packed, timestamp=3)
     assert unpacked == dt
+
+
+def test_too_large_timestamp():
+    # When timestamp64 is too large, conversion to datetime fails due to int64 -> int32 conversion.
+    # https://github.com/msgpack/msgpack-python/issues/696
+    print(msgpack.unpackb(b"\xd7\xff" + b"\x00" * 8, timestamp=3))

From 7082130739d640134e961a384d33ca9939e1f969 Mon Sep 17 00:00:00 2001
From: Inada Naoki <songofacandy@gmail.com>
Date: Fri, 19 Jun 2026 21:45:06 +0900
Subject: [PATCH 09/13] run test with debug build (#702)

---
 .github/workflows/test_debug.yml | 62 ++++++++++++++++++++++++++++++++
 1 file changed, 62 insertions(+)
 create mode 100644 .github/workflows/test_debug.yml

diff --git a/.github/workflows/test_debug.yml b/.github/workflows/test_debug.yml
new file mode 100644
index 0000000..8aeec64
--- /dev/null
+++ b/.github/workflows/test_debug.yml
@@ -0,0 +1,62 @@
+name: Run tests with debug Python
+on:
+  push:
+    branches: [main]
+  pull_request:
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    env:
+      PYTHON_VERSION: 3.14.6
+    steps:
+      - name: Checkout
+        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+
+      - uses: actions/cache@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
+        with:
+          path: /opt/python-debug
+          key: python-debug-${{ runner.os }}-${{ env.PYTHON_VERSION }}
+
+      - name: Install build dependencies
+        if: steps.cache.outputs.cache-hit != 'true'
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y build-essential libssl-dev zlib1g-dev \
+            libbz2-dev libreadline-dev libsqlite3-dev curl libncursesw5-dev \
+            xz-utils tk-dev libxml2-dev libxmlsec1-dev libffi-dev liblzma-dev
+
+      - name: Build Python with Py_DEBUG
+        if: steps.cache.outputs.cache-hit != 'true'
+        run: |
+          wget https://www.python.org/ftp/python/${PYTHON_VERSION}/Python-${PYTHON_VERSION}.tgz
+          tar -xzf Python-${PYTHON_VERSION}.tgz
+          cd Python-${PYTHON_VERSION}
+
+          ./configure --with-pydebug --prefix=/opt/python-debug
+          make -j4
+          sudo make install
+
+      - name: Create venv from debug Python
+        run: |
+          PYDBG_BIN="/opt/python-debug/bin/python3"
+          "$PYDBG_BIN" -m venv .venv
+          echo "$PWD/.venv/bin" >> "$GITHUB_PATH"
+          echo "VIRTUAL_ENV=$PWD/.venv" >> "$GITHUB_ENV"
+
+      - name: Prepare
+        run: |
+          python -m pip install -r requirements.txt pytest
+
+      - name: Build
+        run: |
+          make cython
+          pip install .
+
+      - name: Test (C extension)
+        run: |
+          pytest -v test
+
+      - name: Test (pure Python fallback)
+        run: |
+          MSGPACK_PUREPYTHON=1 pytest -v test

From cf3fd2b0617d50f60d331490f91110721cebaef6 Mon Sep 17 00:00:00 2001
From: Inada Naoki <songofacandy@gmail.com>
Date: Wed, 24 Jun 2026 15:13:45 +0900
Subject: [PATCH 10/13] fix: add reentrant guard to Unpacker.feed() (#704)

fix ##695
---
 msgpack/_unpacker.pyx | 69 +++++++++++++++++++++++++------------------
 test/test_unpack.py   | 19 ++++++++++++
 2 files changed, 60 insertions(+), 28 deletions(-)

diff --git a/msgpack/_unpacker.pyx b/msgpack/_unpacker.pyx
index 26fb377..f758c0c 100644
--- a/msgpack/_unpacker.pyx
+++ b/msgpack/_unpacker.pyx
@@ -305,6 +305,8 @@ cdef class Unpacker:
     Raises ``OutOfData`` when *packed* is incomplete.
     Raises ``FormatError`` when *packed* is not valid msgpack.
     Raises ``StackError`` when *packed* contains too nested.
+    Raises ``RuntimeError`` when ``feed()`` is called while unpacking
+    is in progress (e.g. from a hook).
     Other exceptions can be raised during unpacking.
     """
     cdef unpack_context ctx
@@ -318,6 +320,7 @@ cdef class Unpacker:
     cdef object unicode_errors
     cdef Py_ssize_t max_buffer_size
     cdef uint64_t stream_offset
+    cdef bint _unpacking
 
     def __dealloc__(self):
         unpack_clear(&self.ctx)
@@ -381,6 +384,7 @@ cdef class Unpacker:
         self.buf_head = 0
         self.buf_tail = 0
         self.stream_offset = 0
+        self._unpacking = False
 
         if unicode_errors is not None:
             self.unicode_errors = unicode_errors
@@ -398,6 +402,11 @@ cdef class Unpacker:
         cdef char* buf
         cdef Py_ssize_t buf_len
 
+        if self._unpacking:
+            raise RuntimeError(
+                "Unpacker.feed() cannot be called while unpacking is in progress"
+            )
+
         if self.file_like is not None:
             raise AssertionError(
                     "unpacker.feed() is not be able to use with `file_like`.")
@@ -465,36 +474,40 @@ cdef class Unpacker:
         cdef object obj
         cdef Py_ssize_t prev_head
 
-        while 1:
-            prev_head = self.buf_head
-            if prev_head < self.buf_tail:
-                ret = execute(&self.ctx, self.buf, self.buf_tail, &self.buf_head)
-                self.stream_offset += self.buf_head - prev_head
-            else:
-                ret = 0
-
-            if ret == 1:
-                obj = unpack_data(&self.ctx)
-                unpack_init(&self.ctx)
-                return obj
-            if ret == 0:
-                if self.file_like is not None:
-                    self.read_from_file()
-                    continue
-                if iter:
-                    raise StopIteration("No more data to unpack.")
+        self._unpacking = True
+        try:
+            while 1:
+                prev_head = self.buf_head
+                if prev_head < self.buf_tail:
+                    ret = execute(&self.ctx, self.buf, self.buf_tail, &self.buf_head)
+                    self.stream_offset += self.buf_head - prev_head
                 else:
-                    raise OutOfData("No more data to unpack.")
+                    ret = 0
 
-            unpack_clear(&self.ctx)
-            if ret == -2:
-                raise FormatError
-            elif ret == -3:
-                raise StackError
-            elif PyErr_Occurred():
-                raise
-            else:
-                raise ValueError("Unpack failed: error = %d" % (ret,))
+                if ret == 1:
+                    obj = unpack_data(&self.ctx)
+                    unpack_init(&self.ctx)
+                    return obj
+                if ret == 0:
+                    if self.file_like is not None:
+                        self.read_from_file()
+                        continue
+                    if iter:
+                        raise StopIteration("No more data to unpack.")
+                    else:
+                        raise OutOfData("No more data to unpack.")
+
+                unpack_clear(&self.ctx)
+                if ret == -2:
+                    raise FormatError
+                elif ret == -3:
+                    raise StackError
+                elif PyErr_Occurred():
+                    raise
+                else:
+                    raise ValueError("Unpack failed: error = %d" % (ret,))
+        finally:
+            self._unpacking = False
 
     @cython.critical_section
     def read_bytes(self, Py_ssize_t nbytes):
diff --git a/test/test_unpack.py b/test/test_unpack.py
index 705c16a..81bc976 100644
--- a/test/test_unpack.py
+++ b/test/test_unpack.py
@@ -123,3 +123,22 @@ def test_unpacker_reinit_clears_partial_state():
 
     unpacker.feed(packb({"a": 1}))
     assert unpacker.unpack() == {"a": 1}
+
+
+@mark.skipif(
+    Unpacker.__module__ == "msgpack.fallback",
+    reason="reentrant guard is implemented in C extension only",
+)
+def test_unpacker_reentrant_feed():
+    import struct
+
+    def ext_hook(code, data):
+        # re-entrant feed on the SAME unpacker, large enough to force a buffer realloc
+        up.feed(b"\xc0" * 100)
+        return 0
+
+    up = Unpacker(ext_hook=ext_hook, max_buffer_size=64 * 1024 * 1024)
+    # array(11): [ ExtType(code=5, data=b'A') (fires the re-entrant hook), then 10 more elements ]
+    up.feed(b"\xdc" + struct.pack(">H", 11) + b"\xd4\x05A" + b"\x2a" * 10)
+    with raises(RuntimeError):
+        up.unpack()

From 33fec11eb4b72133f10d0640cc7209b5cc8ed660 Mon Sep 17 00:00:00 2001
From: "dependabot[bot]" <49699333+dependabot[bot]@users.noreply.github.com>
Date: Wed, 24 Jun 2026 15:14:03 +0900
Subject: [PATCH 11/13] Bump actions/checkout from 6.0.3 to 7.0.0 in the
 all-dependencies group (#705)

---
 .github/workflows/docs.yaml      | 2 +-
 .github/workflows/lint.yaml      | 2 +-
 .github/workflows/test.yml       | 2 +-
 .github/workflows/test_debug.yml | 2 +-
 .github/workflows/wheel.yml      | 2 +-
 5 files changed, 5 insertions(+), 5 deletions(-)

diff --git a/.github/workflows/docs.yaml b/.github/workflows/docs.yaml
index 221f5d4..7ae7943 100644
--- a/.github/workflows/docs.yaml
+++ b/.github/workflows/docs.yaml
@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+        uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
 
       - name: Setup Python
         uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405 # v6.2.0
diff --git a/.github/workflows/lint.yaml b/.github/workflows/lint.yaml
index 6ed5a1c..1ad0a1e 100644
--- a/.github/workflows/lint.yaml
+++ b/.github/workflows/lint.yaml
@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-slim
     steps:
       - name: Checkout
-        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+        uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
 
       - name: ruff check
         run: |
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index bc101aa..67c5e52 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -26,7 +26,7 @@ jobs:
 
     steps:
       - name: Checkout
-        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+        uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
 
       - name: Set up Python
         uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405 # v6.2.0
diff --git a/.github/workflows/test_debug.yml b/.github/workflows/test_debug.yml
index 8aeec64..0cfb200 100644
--- a/.github/workflows/test_debug.yml
+++ b/.github/workflows/test_debug.yml
@@ -11,7 +11,7 @@ jobs:
       PYTHON_VERSION: 3.14.6
     steps:
       - name: Checkout
-        uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+        uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
 
       - uses: actions/cache@27d5ce7f107fe9357f9df03efb73ab90386fccae # v5.0.5
         with:
diff --git a/.github/workflows/wheel.yml b/.github/workflows/wheel.yml
index 92fce01..8234ab4 100644
--- a/.github/workflows/wheel.yml
+++ b/.github/workflows/wheel.yml
@@ -26,7 +26,7 @@ jobs:
     name: Build wheels on ${{ matrix.os }}${{ matrix.name_suffix || '' }}
 
     steps:
-      - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6.0.3
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
       - uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405 # v6.2.0
         with:
           python-version: "3.x"

From 951995ecca1f4428967fbbab36f147412d0a5214 Mon Sep 17 00:00:00 2001
From: Inada Naoki <songofacandy@gmail.com>
Date: Wed, 24 Jun 2026 17:14:55 +0900
Subject: [PATCH 12/13] Improve error handling and reporting in unpacking
 functions (#707)

---
 msgpack/_unpacker.pyx     |  6 +-----
 msgpack/unpack.h          |  5 -----
 msgpack/unpack_template.h | 25 +++----------------------
 3 files changed, 4 insertions(+), 32 deletions(-)

diff --git a/msgpack/_unpacker.pyx b/msgpack/_unpacker.pyx
index f758c0c..e046361 100644
--- a/msgpack/_unpacker.pyx
+++ b/msgpack/_unpacker.pyx
@@ -46,7 +46,7 @@ cdef extern from "unpack.h":
         Py_ssize_t count
 
     ctypedef int (*execute_fn)(unpack_context* ctx, const char* data,
-                               Py_ssize_t len, Py_ssize_t* off) except? -1
+                               Py_ssize_t len, Py_ssize_t* off) except -1
     execute_fn unpack_construct
     execute_fn unpack_skip
     execute_fn read_array_header
@@ -206,8 +206,6 @@ def unpackb(object packed, *, object object_hook=None, object list_hook=None,
         raise FormatError
     elif ret == -3:
         raise StackError
-    elif PyErr_Occurred():
-        raise
     else:
         raise ValueError("Unpack failed: error = %d" % (ret,))
 
@@ -502,8 +500,6 @@ cdef class Unpacker:
                     raise FormatError
                 elif ret == -3:
                     raise StackError
-                elif PyErr_Occurred():
-                    raise
                 else:
                     raise ValueError("Unpack failed: error = %d" % (ret,))
         finally:
diff --git a/msgpack/unpack.h b/msgpack/unpack.h
index 55cfdab..eb4330a 100644
--- a/msgpack/unpack.h
+++ b/msgpack/unpack.h
@@ -40,11 +40,6 @@ struct unpack_context;
 typedef struct unpack_context unpack_context;
 typedef int (*execute_fn)(unpack_context *ctx, const char* data, Py_ssize_t len, Py_ssize_t* off);
 
-static inline msgpack_unpack_object unpack_callback_root(unpack_user* u)
-{
-    return NULL;
-}
-
 static inline int unpack_callback_uint16(unpack_user* u, uint16_t d, msgpack_unpack_object* o)
 {
     PyObject *p = PyLong_FromLong((long)d);
diff --git a/msgpack/unpack_template.h b/msgpack/unpack_template.h
index ab5887a..797a2f9 100644
--- a/msgpack/unpack_template.h
+++ b/msgpack/unpack_template.h
@@ -35,11 +35,6 @@ struct unpack_context {
     unsigned int cs;
     unsigned int trail;
     unsigned int top;
-    /*
-    unpack_stack* stack;
-    unsigned int stack_size;
-    unpack_stack embed_stack[MSGPACK_EMBED_STACK_SIZE];
-    */
     unpack_stack stack[MSGPACK_EMBED_STACK_SIZE];
 };
 
@@ -49,22 +44,9 @@ static inline void unpack_init(unpack_context* ctx)
     ctx->cs = CS_HEADER;
     ctx->trail = 0;
     ctx->top = 0;
-    /*
-    ctx->stack = ctx->embed_stack;
-    ctx->stack_size = MSGPACK_EMBED_STACK_SIZE;
-    */
-    ctx->stack[0].obj = unpack_callback_root(&ctx->user);
+    ctx->stack[0].obj = NULL;
 }
 
-/*
-static inline void unpack_destroy(unpack_context* ctx)
-{
-    if(ctx->stack_size != MSGPACK_EMBED_STACK_SIZE) {
-        free(ctx->stack);
-    }
-}
-*/
-
 static inline PyObject* unpack_data(unpack_context* ctx)
 {
     return (ctx)->stack[0].obj;
@@ -94,9 +76,6 @@ static inline int unpack_execute(bool construct, unpack_context* ctx, const char
     unsigned int cs = ctx->cs;
     unsigned int top = ctx->top;
     unpack_stack* stack = ctx->stack;
-    /*
-    unsigned int stack_size = ctx->stack_size;
-    */
     unpack_user* user = &ctx->user;
 
     PyObject* obj = NULL;
@@ -319,6 +298,7 @@ static inline int unpack_execute(bool construct, unpack_context* ctx, const char
                 start_container(_map, _msgpack_load32(uint32_t,n), CT_MAP_KEY);
 
             default:
+                PyErr_Format(PyExc_RuntimeError, "Invalid state: %d", cs);
                 goto _failed;
             }
         }
@@ -355,6 +335,7 @@ _push:
         goto _header_again;
 
     default:
+        PyErr_Format(PyExc_RuntimeError, "Invalid container type: %u", c->ct);
         goto _failed;
     }
 

From 2de627311fb17b1a942d052447c3777cd58b162d Mon Sep 17 00:00:00 2001
From: Inada Naoki <songofacandy@gmail.com>
Date: Wed, 24 Jun 2026 18:17:22 +0900
Subject: [PATCH 13/13] test_unpack.py: add tests for ExtraData (#708)

---
 test/test_unpack.py | 27 ++++++++++++++++++++++++++-
 1 file changed, 26 insertions(+), 1 deletion(-)

diff --git a/test/test_unpack.py b/test/test_unpack.py
index 81bc976..ae6ea10 100644
--- a/test/test_unpack.py
+++ b/test/test_unpack.py
@@ -5,7 +5,15 @@ from io import BytesIO
 
 from pytest import mark, raises
 
-from msgpack import ExtType, OutOfData, Unpacker, packb
+from msgpack import (
+    ExtraData,
+    ExtType,
+    OutOfData,
+    Unpacker,
+    packb,
+    unpack,
+    unpackb,
+)
 
 
 def test_unpack_array_header_from_file():
@@ -142,3 +150,20 @@ def test_unpacker_reentrant_feed():
     up.feed(b"\xdc" + struct.pack(">H", 11) + b"\xd4\x05A" + b"\x2a" * 10)
     with raises(RuntimeError):
         up.unpack()
+
+
+def test_unpackb_raises_extra_data_with_trailing_bytes():
+    packed = packb(42) + packb("trailing")
+    with raises(ExtraData) as exc_info:
+        unpackb(packed)
+    err = exc_info.value
+    assert err.unpacked == 42
+    assert err.extra == packb("trailing")
+
+
+def test_unpack_raises_extra_data_on_stream_with_trailing_bytes():
+    stream = BytesIO(packb(100) + packb(200))
+    with raises(ExtraData) as exc_info:
+        unpack(stream)
+    assert exc_info.value.unpacked == 100
+    assert exc_info.value.extra == packb(200)