Seen when running Python tests with gcc -fsanitize=address (requires LD_PRELOAD=/usr/lib64/libasan.so.4 and ASAN_OPTIONS=detect_leaks=0):
ERROR: test_pack.test_pack.test_packing (subunit.RemotedTestCase) ================================================================= ==7890==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x6020000214d9 at pc 0x7efcad2f836e bp 0x7fffca858730 sp 0x7fffca857ed8 READ of size 10 at 0x6020000214d9 thread T0 #0 0x7efcad2f836d (/usr/lib64/libasan.so.4+0x5136d) #1 0x7efca0a28008 in __pack_write ../src/include/packing.i:345 #2 0x7efca0a2f970 in __wt_schema_project_merge ../src/schema/schema_project.c:470 #3 0x7efca08ff2a6 in __wt_apply_single_idx ../src/cursor/cur_table.c:120 #4 0x7efca08ff61a in __apply_idx ../src/cursor/cur_table.c:154 #5 0x7efca0904914 in __curtable_insert ../src/cursor/cur_table.c:533 #6 0x7efca0dc3a5e in _wrap_Cursor_insert /home/mjc/wt/src/wiredtiger-git/lang/python/wiredtiger_wrap.c:4275 #7 0x7efcacfe2eab in PyEval_EvalFrameEx (/lib64/libpython2.7.so.1.0+0x17feab) #8 0x7efcacfe43f7 in PyEval_EvalCodeEx (/lib64/libpython2.7.so.1.0+0x1813f7) #9 0x7efcacfe1432 in PyEval_EvalFrameEx (/lib64/libpython2.7.so.1.0+0x17e432) #10 0x7efcacfe1d98 in PyEval_EvalFrameEx (/lib64/libpython2.7.so.1.0+0x17ed98) #11 0x7efcacfe43f7 in PyEval_EvalCodeEx (/lib64/libpython2.7.so.1.0+0x1813f7) #12 0x7efcacf33986 (/lib64/libpython2.7.so.1.0+0xd0986) #13 0x7efcacefca52 in PyObject_Call (/lib64/libpython2.7.so.1.0+0x99a52) #14 0x7efcacfdfc42 in PyEval_EvalFrameEx (/lib64/libpython2.7.so.1.0+0x17cc42) #15 0x7efcacfe43f7 in PyEval_EvalCodeEx (/lib64/libpython2.7.so.1.0+0x1813f7) #16 0x7efcacf337ed (/lib64/libpython2.7.so.1.0+0xd07ed) #17 0x7efcacefca52 in PyObject_Call (/lib64/libpython2.7.so.1.0+0x99a52) #18 0x7efcacf2888d (/lib64/libpython2.7.so.1.0+0xc588d) #19 0x7efcacefca52 in PyObject_Call (/lib64/libpython2.7.so.1.0+0x99a52) #20 0x7efcacfb6a2a (/lib64/libpython2.7.so.1.0+0x153a2a) #21 0x7efcacefca52 in PyObject_Call (/lib64/libpython2.7.so.1.0+0x99a52) #22 0x7efcacfdf453 in PyEval_EvalFrameEx (/lib64/libpython2.7.so.1.0+0x17c453) #23 0x7efcacfe43f7 in PyEval_EvalCodeEx (/lib64/libpython2.7.so.1.0+0x1813f7) #24 0x7efcacfe1432 in PyEval_EvalFrameEx (/lib64/libpython2.7.so.1.0+0x17e432) #25 0x7efcacfe43f7 in PyEval_EvalCodeEx (/lib64/libpython2.7.so.1.0+0x1813f7) #26 0x7efcacfe1432 in PyEval_EvalFrameEx (/lib64/libpython2.7.so.1.0+0x17e432) #27 0x7efcacfe43f7 in PyEval_EvalCodeEx (/lib64/libpython2.7.so.1.0+0x1813f7) #28 0x7efcacf33986 (/lib64/libpython2.7.so.1.0+0xd0986) #29 0x7efcacefca52 in PyObject_Call (/lib64/libpython2.7.so.1.0+0x99a52) #30 0x7efcacfdfc42 in PyEval_EvalFrameEx (/lib64/libpython2.7.so.1.0+0x17cc42) #31 0x7efcacfe43f7 in PyEval_EvalCodeEx (/lib64/libpython2.7.so.1.0+0x1813f7) #32 0x7efcacf337ed (/lib64/libpython2.7.so.1.0+0xd07ed) #33 0x7efcacefca52 in PyObject_Call (/lib64/libpython2.7.so.1.0+0x99a52) #34 0x7efcacf2888d (/lib64/libpython2.7.so.1.0+0xc588d) #35 0x7efcacefca52 in PyObject_Call (/lib64/libpython2.7.so.1.0+0x99a52) #36 0x7efcacfb6a2a (/lib64/libpython2.7.so.1.0+0x153a2a) #37 0x7efcacefca52 in PyObject_Call (/lib64/libpython2.7.so.1.0+0x99a52) #38 0x7efcacfdf453 in PyEval_EvalFrameEx (/lib64/libpython2.7.so.1.0+0x17c453) #39 0x7efcacfe1d98 in PyEval_EvalFrameEx (/lib64/libpython2.7.so.1.0+0x17ed98) #40 0x7efcacfe1d98 in PyEval_EvalFrameEx (/lib64/libpython2.7.so.1.0+0x17ed98) #41 0x7efcacfe43f7 in PyEval_EvalCodeEx (/lib64/libpython2.7.so.1.0+0x1813f7) #42 0x7efcacfe4608 in PyEval_EvalCode (/lib64/libpython2.7.so.1.0+0x181608) #43 0x7efcacfbc81e (/lib64/libpython2.7.so.1.0+0x15981e) #44 0x7efcacfbc8c9 in PyRun_FileExFlags (/lib64/libpython2.7.so.1.0+0x1598c9) #45 0x7efcacfbd8cd in PyRun_SimpleFileExFlags (/lib64/libpython2.7.so.1.0+0x15a8cd) #46 0x7efcacfb061d in Py_Main (/lib64/libpython2.7.so.1.0+0x14d61d) #47 0x7efcac176509 in __libc_start_main (/lib64/libc.so.6+0x20509) #48 0x55d4a4b02779 in _start (/usr/bin/python2.7+0x779) 0x6020000214d9 is located 0 bytes to the right of 9-byte region [0x6020000214d0,0x6020000214d9) allocated by thread T0 here: #0 0x7efcad385c40 in realloc (/usr/lib64/libasan.so.4+0xdec40) #1 0x7efca09ad016 in __realloc_func ../src/os_common/os_alloc.c:130 #2 0x7efca09ad154 in __wt_realloc_noclear ../src/os_common/os_alloc.c:171 #3 0x7efca0a75bfe in __wt_buf_grow_worker ../src/support/scratch.c:48 #4 0x7efca0a2671e in __wt_buf_grow ../src/include/buf.i:18 #5 0x7efca0a2e667 in __wt_schema_project_slice ../src/schema/schema_project.c:369 #6 0x7efca0900ab7 in __wt_curtable_set_value ../src/cursor/cur_table.c:258 #7 0x7efca0dc6a2c in __wt_cursor__set_value /home/mjc/wt/src/wiredtiger-git/lang/python/wiredtiger_wrap.c:3480 #8 0x7efca0dc6a2c in _wrap_Cursor__set_value /home/mjc/wt/src/wiredtiger-git/lang/python/wiredtiger_wrap.c:4747 SUMMARY: AddressSanitizer: heap-buffer-overflow (/usr/lib64/libasan.so.4+0x5136d) Shadow bytes around the buggy address: 0x0c047fffc240: fa fa 07 fa fa fa 03 fa fa fa 04 fa fa fa 00 fa 0x0c047fffc250: fa fa fd fd fa fa 04 fa fa fa fd fa fa fa fd fa 0x0c047fffc260: fa fa 07 fa fa fa fd fa fa fa fd fa fa fa fd fd 0x0c047fffc270: fa fa fd fd fa fa 00 03 fa fa 00 05 fa fa 00 fa 0x0c047fffc280: fa fa 00 00 fa fa 02 fa fa fa 00 fa fa fa 04 fa =>0x0c047fffc290: fa fa 01 fa fa fa 00 00 fa fa 00[01]fa fa 00 fa 0x0c047fffc2a0: fa fa 00 fa fa fa 00 01 fa fa fa fa fa fa 00 00 0x0c047fffc2b0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c047fffc2c0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c047fffc2d0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 0x0c047fffc2e0: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa 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 ==7890==ABORTING
This is surprising because that test has been around forever and nothing in that area has changed recently.