mb_get_time global-buffer-overflow about mb-system

[schwehr]

More direct testing to demonstrate the buffer overflow:

TEST(MbGetTime, AsanFailure) {
  double t = -1.0;
  int time[7] = {0, 0, 0, 0, 0, 0, 0};
  EXPECT_EQ(MB_FAILURE, mb_get_time(0, time, &t));
}

TEST(MbGetTime, AsanFailureNegative) {
  double t = -1.0;
  int time[7] = {-1, -1, -1, -1, -1, -1, -1};
  EXPECT_EQ(MB_FAILURE, mb_get_time(0, time, &t));
}

dbg2  MBIO function <mb_get_time> called
dbg2  Input arguments:
dbg2       verbose: 0
dbg2       year:    0
dbg2       month:   0
dbg2       day:     0
dbg2       hour:    0
dbg2       minute:  0
dbg2       second:  0
dbg2       microsec:0
dbg2       time_d:  0x7f2196462a20
dbg2       *time_d: -1.000000
=================================================================
==7072==ERROR: AddressSanitizer: global-buffer-overflow on address 0x7f21a143e17c at pc 0x7f21a173ac3d bp 0x7ffd8515cb60 sp 0x7ffd8515cb58
READ of size 4 at 0x7f21a143e17c thread T0
    #0 0x7f21a173ac3c in mb_get_time third_party/mbsystem/mbio/mb_time.c:58:16
    #1 0x7f21a260cb4d in (anonymous namespace)::MbGetTime_AsanFailure_Test::TestBody() third_party/mbsystem/test/mbio/mb_time_test.cc:87:3

0x7f21a143e17c is located 4 bytes to the left of global variable 'yday' defined in 'third_party/mbsystem/mbio/mb_time.c:30:18' (0x7f21a143e180) of size 48
0x7f21a143e17c is located 36 bytes to the right of global variable '<string literal>' defined in 'third_party/mbsystem/mbio/mb_time.c:49:19' (0x7f21a143e140) of size 24
  '<string literal>' is ascii string 'dbg2       *time_d: %f
'
SUMMARY: AddressSanitizer: global-buffer-overflow third_party/mbsystem/mbio/mb_time.c:58:16 in mb_get_time
Shadow bytes around the buggy address:
  0x0fe4b427fbd0: 00 04 f9 f9 f9 f9 f9 f9 00 00 00 f9 f9 f9 f9 f9
  0x0fe4b427fbe0: 00 00 00 f9 f9 f9 f9 f9 00 00 00 f9 f9 f9 f9 f9
  0x0fe4b427fbf0: 00 00 00 f9 f9 f9 f9 f9 00 00 00 f9 f9 f9 f9 f9
  0x0fe4b427fc00: 00 00 00 f9 f9 f9 f9 f9 00 00 00 f9 f9 f9 f9 f9
  0x0fe4b427fc10: 00 00 00 f9 f9 f9 f9 f9 00 00 00 f9 f9 f9 f9 f9
=>0x0fe4b427fc20: 00 00 00 f9 f9 f9 f9 f9 00 00 00 f9 f9 f9 f9[f9]
  0x0fe4b427fc30: 00 00 00 00 00 00 f9 f9 f9 f9 f9 f9 00 00 00 00
  0x0fe4b427fc40: 00 00 00 00 05 f9 f9 f9 f9 f9 f9 f9 00 00 05 f9
  0x0fe4b427fc50: f9 f9 f9 f9 00 00 00 f9 f9 f9 f9 f9 00 00 06 f9
  0x0fe4b427fc60: f9 f9 f9 f9 00 00 00 f9 f9 f9 f9 f9 00 04 f9 f9
  0x0fe4b427fc70: f9 f9 f9 f9 00 00 00 00 00 00 00 07 f9 f9 f9 f9
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
  Shadow gap:              cc