import io
class RAW(io.RawIOBase):
def readable(self):
return True
def readinto(self, b):
tw.detach()
b[:3] = b"abc"
return 3
tw = io.TextIOWrapper(io.BufferedReader(RAW()), encoding="utf-8")
tw.read()Exception ignored while finalizing file <_io.BufferedReader>:
Traceback (most recent call last):
File "/repro/audit4/repro/textio_detach_uaf.py", line 21, in readinto
tw.detach()
~~~~~~~~~^^
RuntimeError: reentrant call inside <_io.BufferedReader>
=================================================================
==1==ERROR: AddressSanitizer: heap-use-after-free on address 0x50f000039ff0 at pc 0xaaaad92e3ca4 bp 0xffffeddd0980 sp 0xffffeddd0970
WRITE of size 8 at 0x50f000039ff0 thread T0
#0 0xaaaad92e3ca0 in _io__Buffered_read_impl Modules/_io/bufferedio.c:1022
#1 0xaaaad92e3ca0 in _io__Buffered_read Modules/_io/clinic/bufferedio.c.h:677
#2 0xaaaad8869b50 in _PyObject_VectorcallTstate Include/internal/pycore_call.h:144
#3 0xaaaad8869b50 in PyObject_VectorcallMethod Objects/call.c:921
#4 0xaaaad92eb514 in PyObject_CallMethodNoArgs Include/cpython/abstract.h:65
#5 0xaaaad92eb514 in buffer_callmethod_noargs Modules/_io/textio.c:781
#6 0xaaaad93061e8 in _io_TextIOWrapper_read_impl Modules/_io/textio.c:2083
#7 0xaaaad93061e8 in _io_TextIOWrapper_read Modules/_io/clinic/textio.c.h:857
#8 0xaaaad8866320 in _PyObject_VectorcallTstate Include/internal/pycore_call.h:144
#9 0xaaaad8866320 in PyObject_Vectorcall Objects/call.c:327
#10 0xaaaad8eb1bc8 in _Py_VectorCallInstrumentation_StackRefSteal Python/ceval.c:768
#11 0xaaaad85e1de8 in _PyEval_EvalFrameDefault Python/generated_cases.c.h:1906
#12 0xaaaad8ed0b1c in _PyEval_EvalFrame Include/internal/pycore_ceval.h:122
#13 0xaaaad8ed0b1c in _PyEval_Vector Python/ceval.c:2174
#14 0xaaaad8ed0b1c in PyEval_EvalCode Python/ceval.c:679
#15 0xaaaad90cfeb4 in run_mod Python/pythonrun.c:1509
#16 0xaaaad90d0d38 in _PyRun_File Python/pythonrun.c:1332
#17 0xaaaad90d4ffc in _PyRun_SimpleFile Python/pythonrun.c:544
#18 0xaaaad90d8dd0 in _PyRun_AnyFile Python/pythonrun.c:92
#19 0xaaaad91a390c in pymain_run_file_obj Modules/main.c:478
#20 0xaaaad91a390c in pymain_run_file Modules/main.c:494
#21 0xaaaad91a390c in pymain_run_python Modules/main.c:804
#22 0xaaaad91a390c in Py_RunMain Modules/main.c:891
#23 0xaaaad91a5c38 in pymain_main Modules/main.c:921
#24 0xaaaad91a5c38 in Py_BytesMain Modules/main.c:945
#25 0xffff9b6684c0 (/lib/aarch64-linux-gnu/libc.so.6+0x284c0) (BuildId: 27027b96e5b8c475fc327aa445bea1c71d37b4e2)
#26 0xffff9b668594 in __libc_start_main (/lib/aarch64-linux-gnu/libc.so.6+0x28594) (BuildId: 27027b96e5b8c475fc327aa445bea1c71d37b4e2)
#27 0xaaaad864beec in _start (/src/cpython/python+0x183beec) (BuildId: eba909a3db0adabacf151d7dc3081dda7999191a)
0x50f000039ff0 is located 128 bytes inside of 168-byte region [0x50f000039f70,0x50f00003a018)
freed by thread T0 here:
#0 0xffff9c0061b4 in free ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:52
#1 0xaaaad92cd8dc in buffered_dealloc Modules/_io/bufferedio.c:444
#2 0xaaaad8a57ab0 in _Py_Dealloc Objects/object.c:3334
#3 0xaaaad860fea0 in Py_DECREF_MORTAL Include/internal/pycore_object.h:449
#4 0xaaaad860fea0 in PyStackRef_XCLOSE Include/internal/pycore_stackref.h:726
#5 0xaaaad860fea0 in _PyEval_EvalFrameDefault Python/generated_cases.c.h:11163
#6 0xaaaad8ed1a00 in _PyEval_EvalFrame Include/internal/pycore_ceval.h:122
#7 0xaaaad8ed1a00 in _PyEval_Vector Python/ceval.c:2174
#8 0xaaaad8864e58 in _PyObject_VectorcallTstate Include/internal/pycore_call.h:144
#9 0xaaaad8864e58 in object_vacall Objects/call.c:823
#10 0xaaaad886a2c8 in PyObject_CallMethodObjArgs Objects/call.c:960
#11 0xaaaad92b253c in _io__RawIOBase_read_impl Modules/_io/iobase.c:936
#12 0xaaaad92b253c in _io__RawIOBase_read Modules/_io/clinic/iobase.c.h:425
#13 0xaaaad8865880 in _PyObject_VectorcallTstate Include/internal/pycore_call.h:144
#14 0xaaaad8865880 in _PyObject_CallFunctionVa Objects/call.c:552
#15 0xaaaad8867aa0 in callmethod Objects/call.c:626
#16 0xaaaad8867aa0 in _PyObject_CallMethod Objects/call.c:694
#17 0xaaaad92b1cec in _io__RawIOBase_readall_impl Modules/_io/iobase.c:979
#18 0xaaaad92b1cec in _io__RawIOBase_readall Modules/_io/clinic/iobase.c.h:446
#19 0xaaaad92e2d88 in _PyObject_VectorcallTstate Include/internal/pycore_call.h:144
#20 0xaaaad92e2d88 in _PyObject_CallNoArgs Include/internal/pycore_call.h:160
#21 0xaaaad92e2d88 in _bufferedreader_read_all Modules/_io/bufferedio.c:1717
#22 0xaaaad92e2d88 in _io__Buffered_read_impl Modules/_io/bufferedio.c:1010
#23 0xaaaad92e2d88 in _io__Buffered_read Modules/_io/clinic/bufferedio.c.h:677
#24 0xaaaad8869b50 in _PyObject_VectorcallTstate Include/internal/pycore_call.h:144
#25 0xaaaad8869b50 in PyObject_VectorcallMethod Objects/call.c:921
#26 0xaaaad92eb514 in PyObject_CallMethodNoArgs Include/cpython/abstract.h:65
#27 0xaaaad92eb514 in buffer_callmethod_noargs Modules/_io/textio.c:781
#28 0xaaaad93061e8 in _io_TextIOWrapper_read_impl Modules/_io/textio.c:2083
#29 0xaaaad93061e8 in _io_TextIOWrapper_read Modules/_io/clinic/textio.c.h:857
#30 0xaaaad8866320 in _PyObject_VectorcallTstate Include/internal/pycore_call.h:144
#31 0xaaaad8866320 in PyObject_Vectorcall Objects/call.c:327
#32 0xaaaad8eb1bc8 in _Py_VectorCallInstrumentation_StackRefSteal Python/ceval.c:768
#33 0xaaaad85e1de8 in _PyEval_EvalFrameDefault Python/generated_cases.c.h:1906
#34 0xaaaad8ed0b1c in _PyEval_EvalFrame Include/internal/pycore_ceval.h:122
#35 0xaaaad8ed0b1c in _PyEval_Vector Python/ceval.c:2174
#36 0xaaaad8ed0b1c in PyEval_EvalCode Python/ceval.c:679
#37 0xaaaad90cfeb4 in run_mod Python/pythonrun.c:1509
#38 0xaaaad90d0d38 in _PyRun_File Python/pythonrun.c:1332
#39 0xaaaad90d4ffc in _PyRun_SimpleFile Python/pythonrun.c:544
#40 0xaaaad90d8dd0 in _PyRun_AnyFile Python/pythonrun.c:92
#41 0xaaaad91a390c in pymain_run_file_obj Modules/main.c:478
#42 0xaaaad91a390c in pymain_run_file Modules/main.c:494
#43 0xaaaad91a390c in pymain_run_python Modules/main.c:804
#44 0xaaaad91a390c in Py_RunMain Modules/main.c:891
#45 0xaaaad91a5c38 in pymain_main Modules/main.c:921
#46 0xaaaad91a5c38 in Py_BytesMain Modules/main.c:945
#47 0xffff9b6684c0 (/lib/aarch64-linux-gnu/libc.so.6+0x284c0) (BuildId: 27027b96e5b8c475fc327aa445bea1c71d37b4e2)
#48 0xffff9b668594 in __libc_start_main (/lib/aarch64-linux-gnu/libc.so.6+0x28594) (BuildId: 27027b96e5b8c475fc327aa445bea1c71d37b4e2)
#49 0xaaaad864beec in _start (/src/cpython/python+0x183beec) (BuildId: eba909a3db0adabacf151d7dc3081dda7999191a)
previously allocated by thread T0 here:
#0 0xffff9c0076d0 in malloc ../../../../src/libsanitizer/asan/asan_malloc_linux.cpp:69
#1 0xaaaad8b7077c in _PyObject_MallocWithType Include/internal/pycore_object_alloc.h:46
#2 0xaaaad8b7077c in _PyType_AllocNoTrack Objects/typeobject.c:2498
#3 0xaaaad8b70e00 in PyType_GenericAlloc Objects/typeobject.c:2529
#4 0xaaaad8b76808 in type_call Objects/typeobject.c:2442
#5 0xaaaad8864250 in _PyObject_MakeTpCall Objects/call.c:242
#6 0xaaaad8eb1bc8 in _Py_VectorCallInstrumentation_StackRefSteal Python/ceval.c:768
#7 0xaaaad85e1de8 in _PyEval_EvalFrameDefault Python/generated_cases.c.h:1906
#8 0xaaaad8ed0b1c in _PyEval_EvalFrame Include/internal/pycore_ceval.h:122
#9 0xaaaad8ed0b1c in _PyEval_Vector Python/ceval.c:2174
#10 0xaaaad8ed0b1c in PyEval_EvalCode Python/ceval.c:679
#11 0xaaaad90cfeb4 in run_mod Python/pythonrun.c:1509
#12 0xaaaad90d0d38 in _PyRun_File Python/pythonrun.c:1332
#13 0xaaaad90d4ffc in _PyRun_SimpleFile Python/pythonrun.c:544
#14 0xaaaad90d8dd0 in _PyRun_AnyFile Python/pythonrun.c:92
#15 0xaaaad91a390c in pymain_run_file_obj Modules/main.c:478
#16 0xaaaad91a390c in pymain_run_file Modules/main.c:494
#17 0xaaaad91a390c in pymain_run_python Modules/main.c:804
#18 0xaaaad91a390c in Py_RunMain Modules/main.c:891
#19 0xaaaad91a5c38 in pymain_main Modules/main.c:921
#20 0xaaaad91a5c38 in Py_BytesMain Modules/main.c:945
#21 0xffff9b6684c0 (/lib/aarch64-linux-gnu/libc.so.6+0x284c0) (BuildId: 27027b96e5b8c475fc327aa445bea1c71d37b4e2)
#22 0xffff9b668594 in __libc_start_main (/lib/aarch64-linux-gnu/libc.so.6+0x28594) (BuildId: 27027b96e5b8c475fc327aa445bea1c71d37b4e2)
#23 0xaaaad864beec in _start (/src/cpython/python+0x183beec) (BuildId: eba909a3db0adabacf151d7dc3081dda7999191a)
SUMMARY: AddressSanitizer: heap-use-after-free Modules/_io/bufferedio.c:1022 in _io__Buffered_read_impl
Shadow bytes around the buggy address:
0x50f000039d00: fd fd fd fd fd fd fd fd fd fa fa fa fa fa fa fa
0x50f000039d80: fa fa 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x50f000039e00: 00 00 00 00 00 00 00 fa fa fa fa fa fa fa fa fa
0x50f000039e80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x50f000039f00: 00 00 00 00 00 fa fa fa fa fa fa fa fa fa fd fd
=>0x50f000039f80: fd fd fd fd fd fd fd fd fd fd fd fd fd fd[fd]fd
0x50f00003a000: fd fd fd fa fa fa fa fa fa fa fa fa fd fd fd fd
0x50f00003a080: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd
0x50f00003a100: fd fa fa fa fa fa fa fa fa fa fd fd fd fd fd fd
0x50f00003a180: fd fd fd fd fd fd fd fd fd fd fd fd fd fd fd fa
0x50f00003a200: fa fa fa fa fa fa fa fa fd fd fd fd fd fd fd fd
Shadow byte legend (one shadow byte represents 8 application bytes):
Addressable: 00
Partially addressable: 01 02 03 04 05 06 07
Heap left redzone: fa
Freed heap region: fd
Stack left redzone: f1
Stack mid redzone: f2
Stack right redzone: f3
Stack after return: f5
Stack use after scope: f8
Global redzone: f9
Global init order: f6
Poisoned by user: f7
Container overflow: fc
Array cookie: ac
Intra object redzone: bb
ASan internal: fe
Left alloca redzone: ca
Right alloca redzone: cb
==1==ABORTING
Bug description:
CPython versions tested on:
CPython main branch
Operating systems tested on:
Linux