ASan: Fix stack overflow in system_unittest
This change fixes the following buffer overflow in system_unittest,
found by running `make tests` with AddressSanitizer:
==30977==ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7ffddc9c3055 at pc 0x7ff7ec00f2d5 bp 0x7ffddc9c2ca0 sp 0x7ffddc9c2448
READ of size 6 at 0x7ffddc9c3055 thread T0
#0 0x7ff7ec00f2d4 (/usr/lib/x86_64-linux-gnu/libasan.so.2+0x472d4)
#1 0x44fa17 in write_pid_to_path_basic_Test::TestBody() system_unittest.cc:132
Address 0x7ffddc9c3055 is located in stack of thread T0 at offset 805 in frame
#0 0x44ef6f in write_pid_to_path_basic_Test::TestBody() system_unittest.cc:121
This frame has 7 object(s):
[32, 40) 'path'
[96, 104) 'fp'
[160, 176) 'gtest_ar'
[224, 256) '<unknown>'
[288, 320) '<unknown>'
[352, 744) 'ss'
[800, 805) 'data' <== Memory access at offset 805 overflows this variable
HINT: this may be a false positive if your program uses some custom stack unwind mechanism or swapcontext
(longjmp and C++ exceptions *are* supported)
SUMMARY: AddressSanitizer: stack-buffer-overflow ??:0 ??
Shadow bytes around the buggy address:
0x10003b9305b0: f2 f2 00 f4 f4 f4 f2 f2 f2 f2 00 00 f4 f4 f2 f2
0x10003b9305c0: f2 f2 00 00 00 00 f2 f2 f2 f2 00 00 00 00 f2 f2
0x10003b9305d0: f2 f2 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x10003b9305e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x10003b9305f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>0x10003b930600: 00 00 00 f4 f4 f4 f2 f2 f2 f2[05]f4 f4 f4 f3 f3
0x10003b930610: f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 00 00
0x10003b930620: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1
0x10003b930630: 00 00 f4 f4 f3 f3 f3 f3 00 00 00 00 00 00 00 00
0x10003b930640: 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1 f1 f1
0x10003b930650: 00 00 f4 f4 f3 f3 f3 f3 00 00 00 00 00 00 00 00
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
Heap right redzone: fb
Freed heap region: fd
Stack left redzone: f1
Stack mid redzone: f2
Stack right redzone: f3
Stack partial redzone: f4
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
==30977==ABORTING
Bug: None
Test: make tests (with -fsanitize=address in {C,CXX}FLAGS).
Change-Id: If5145d60f34664c39b560bf5a739bdac7ee689b6
1 file changed