diff options
| -rw-r--r-- | Lib/test/test_memoryio.py | 14 | ||||
| -rw-r--r-- | Misc/NEWS.d/next/Library/2023-10-23-13-53-58.gh-issue-111174.Oohmzd.rst | 2 | ||||
| -rw-r--r-- | Modules/_io/bytesio.c | 7 |
3 files changed, 20 insertions, 3 deletions
diff --git a/Lib/test/test_memoryio.py b/Lib/test/test_memoryio.py index cd2faba..7312992 100644 --- a/Lib/test/test_memoryio.py +++ b/Lib/test/test_memoryio.py @@ -463,6 +463,20 @@ class PyBytesIOTest(MemoryTestMixin, MemorySeekTestMixin, unittest.TestCase): memio.close() self.assertRaises(ValueError, memio.getbuffer) + def test_getbuffer_empty(self): + memio = self.ioclass() + buf = memio.getbuffer() + self.assertEqual(bytes(buf), b"") + # Trying to change the size of the BytesIO while a buffer is exported + # raises a BufferError. + self.assertRaises(BufferError, memio.write, b'x') + buf2 = memio.getbuffer() + self.assertRaises(BufferError, memio.write, b'x') + buf.release() + self.assertRaises(BufferError, memio.write, b'x') + buf2.release() + memio.write(b'x') + def test_read1(self): buf = self.buftype("1234567890") self.assertEqual(self.ioclass(buf).read1(), buf) diff --git a/Misc/NEWS.d/next/Library/2023-10-23-13-53-58.gh-issue-111174.Oohmzd.rst b/Misc/NEWS.d/next/Library/2023-10-23-13-53-58.gh-issue-111174.Oohmzd.rst new file mode 100644 index 0000000..95c3154 --- /dev/null +++ b/Misc/NEWS.d/next/Library/2023-10-23-13-53-58.gh-issue-111174.Oohmzd.rst @@ -0,0 +1,2 @@ +Fix crash in :meth:`io.BytesIO.getbuffer` called repeatedly for empty +BytesIO. diff --git a/Modules/_io/bytesio.c b/Modules/_io/bytesio.c index 8077305..7636394 100644 --- a/Modules/_io/bytesio.c +++ b/Modules/_io/bytesio.c @@ -124,12 +124,13 @@ unshare_buffer(bytesio *self, size_t size) static int resize_buffer(bytesio *self, size_t size) { + assert(self->buf != NULL); + assert(self->exports == 0); + /* Here, unsigned types are used to avoid dealing with signed integer overflow, which is undefined in C. */ size_t alloc = PyBytes_GET_SIZE(self->buf); - assert(self->buf != NULL); - /* For simplicity, stay in the range of the signed type. Anyway, Python doesn't allow strings to be longer than this. */ if (size > PY_SSIZE_T_MAX) @@ -1072,7 +1073,7 @@ bytesiobuf_getbuffer(bytesiobuf *obj, Py_buffer *view, int flags) "bytesiobuf_getbuffer: view==NULL argument is obsolete"); return -1; } - if (SHARED_BUF(b)) { + if (b->exports == 0 && SHARED_BUF(b)) { if (unshare_buffer(b, b->string_size) < 0) return -1; } |