Re: [PATCH] core/gatt-database: Fix memory corruption

[Stefan Seyfried <stefan.seyfried@googlemail.com>]

Am 11.03.2015 um 15:35 schrieb Andrejs Hanins:
> Pointer to on-stack variable was returned from pending_write_new.

I still get a crash in the tests when running with memory debugging
enabled (which is default in openSUSE Build Service):

$> MALLOC_CHECK_=3 MALLOC_PERTURB_=69 unit/test-gatt

/TP/GAC/CL/BV-01-C - init
/TP/GAC/CL/BV-01-C - setup
[...]
/TP/GAR/CL/BV-01-C - setup complete
/TP/GAR/CL/BV-01-C - run
/TP/GAR/CL/BV-01-C - test passed
Segmentation fault

Program received signal SIGSEGV, Segmentation fault.
0x000055555558cb70 in bt_att_send (att=0x4000000f300432d, opcode=opcode@entry=24 '\030', 
    pdu=pdu@entry=0x7fffffff4a0f, length=length@entry=1, 
    callback=callback@entry=0x55555558fc30 <cancel_long_write_cb>, user_data=0x5555557b1ca0, 
    destroy=destroy@entry=0x0) at src/shared/att.c:1135
1135            if (!att || !att->io)
(gdb) bt
#0  0x000055555558cb70 in bt_att_send (att=0x4000000f300432d, opcode=opcode@entry=24 '\030', 
    pdu=pdu@entry=0x7fffffff4a0f, length=length@entry=1, 
    callback=callback@entry=0x55555558fc30 <cancel_long_write_cb>, user_data=0x5555557b1ca0, 
    destroy=destroy@entry=0x0) at src/shared/att.c:1135
#1  0x0000555555591039 in cancel_long_write_req (client=<optimized out>, req=<optimized out>)
    at src/shared/gatt-client.c:1791
#2  0x00005555555910ab in cancel_request (data=0x5555557b1e80) at src/shared/gatt-client.c:1855
#3  0x0000555555597903 in queue_remove_all (queue=<optimized out>, function=function@entry=0x0, 
    user_data=user_data@entry=0x0, destroy=destroy@entry=0x555555591060 <cancel_request>)
    at src/shared/queue.c:387
#4  0x00005555555917cd in bt_gatt_client_cancel_all (client=client@entry=0x5555557b36f0)
    at src/shared/gatt-client.c:1866
#5  0x0000555555591839 in bt_gatt_client_free (client=0x5555557b36f0) at src/shared/gatt-client.c:1569
#6  0x0000555555589439 in destroy_context (context=0x5555557b1bb0) at unit/test-gatt.c:284
#7  context_quit (user_data=0x5555557b1bb0) at unit/test-gatt.c:312
#8  0x000055555558d59b in handle_rsp (pdu_len=<optimized out>, pdu=0x5555557c6571 "\001\002\003\001)", 
    opcode=11 '\v', att=0x5555557b2e90) at src/shared/att.c:640
#9  can_read_data (io=<optimized out>, user_data=0x5555557b2e90) at src/shared/att.c:813
#10 0x0000555555596ec5 in watch_callback (channel=<optimized out>, cond=<optimized out>, 
    user_data=<optimized out>) at src/shared/io-glib.c:170
#11 0x00007ffff7b198e5 in g_main_context_dispatch () from /usr/lib64/libglib-2.0.so.0
#12 0x00007ffff7b19c48 in ?? () from /usr/lib64/libglib-2.0.so.0
#13 0x00007ffff7b19f0a in g_main_loop_run () from /usr/lib64/libglib-2.0.so.0
#14 0x000055555558c031 in tester_run () at src/shared/tester.c:830
#15 0x0000555555587e19 in main (argc=1, argv=0x7fffffffdc58) at unit/test-gatt.c:3182

Valgrind also complains loudly:
$> valgrind unit/test-gatt > /dev/null 
==20817== Memcheck, a memory error detector
==20817== Copyright (C) 2002-2013, and GNU GPL'd, by Julian Seward et al.
==20817== Using Valgrind-3.10.0 and LibVEX; rerun with -h for copyright info
==20817== Command: unit/test-gatt
==20817== 
==20817== Syscall param socketcall.bind(my_addr.sa_data) points to uninitialised byte(s)
==20817==    at 0x522A737: bind (in /lib64/libc-2.21.so)
==20817==    by 0x14BBC2: ecb_aes_setup (crypto.c:110)
==20817==    by 0x14BBC2: bt_crypto_new (crypto.c:148)
==20817==    by 0x140788: bt_att_new (att.c:937)
==20817==    by 0x13EA4B: create_context.constprop.24 (test-gatt.c:592)
==20817==    by 0x13F2E2: run_callback (tester.c:412)
==20817==    by 0x4E808E4: g_main_context_dispatch (in /usr/lib64/libglib-2.0.so.0.4200.1)
==20817==    by 0x4E80C47: ??? (in /usr/lib64/libglib-2.0.so.0.4200.1)
==20817==    by 0x4E80F09: g_main_loop_run (in /usr/lib64/libglib-2.0.so.0.4200.1)
==20817==    by 0x140030: tester_run (tester.c:830)
==20817==    by 0x13BE18: main (test-gatt.c:3182)
==20817==  Address 0xffeff6aa8 is on thread 1's stack
==20817==  in frame #1, created by bt_crypto_new (crypto.c:141)
==20817== 
==20817== Syscall param socketcall.bind(my_addr.sa_data) points to uninitialised byte(s)
==20817==    at 0x522A737: bind (in /lib64/libc-2.21.so)
==20817==    by 0x14BC4B: cmac_aes_setup (crypto.c:132)
==20817==    by 0x14BC4B: bt_crypto_new (crypto.c:161)
==20817==    by 0x140788: bt_att_new (att.c:937)
==20817==    by 0x13EA4B: create_context.constprop.24 (test-gatt.c:592)
==20817==    by 0x13F2E2: run_callback (tester.c:412)
==20817==    by 0x4E808E4: g_main_context_dispatch (in /usr/lib64/libglib-2.0.so.0.4200.1)
==20817==    by 0x4E80C47: ??? (in /usr/lib64/libglib-2.0.so.0.4200.1)
==20817==    by 0x4E80F09: g_main_loop_run (in /usr/lib64/libglib-2.0.so.0.4200.1)
==20817==    by 0x140030: tester_run (tester.c:830)
==20817==    by 0x13BE18: main (test-gatt.c:3182)
==20817==  Address 0xffeff6aa8 is on thread 1's stack
==20817==  in frame #1, created by bt_crypto_new (crypto.c:141)
==20817== 
==20817== Invalid read of size 1
==20817==    at 0x145076: cancel_request (gatt-client.c:1854)
==20817==    by 0x14B902: queue_remove_all (queue.c:387)
==20817==    by 0x1457CC: bt_gatt_client_cancel_all (gatt-client.c:1866)
==20817==    by 0x145838: bt_gatt_client_free (gatt-client.c:1569)
==20817==    by 0x13D438: destroy_context (test-gatt.c:284)
==20817==    by 0x13D438: context_quit (test-gatt.c:312)
==20817==    by 0x14159A: handle_rsp (att.c:640)
==20817==    by 0x14159A: can_read_data (att.c:813)
==20817==    by 0x14AEC4: watch_callback (io-glib.c:170)
==20817==    by 0x4E808E4: g_main_context_dispatch (in /usr/lib64/libglib-2.0.so.0.4200.1)
==20817==    by 0x4E80C47: ??? (in /usr/lib64/libglib-2.0.so.0.4200.1)
==20817==    by 0x4E80F09: g_main_loop_run (in /usr/lib64/libglib-2.0.so.0.4200.1)
==20817==    by 0x140030: tester_run (tester.c:830)
==20817==    by 0x13BE18: main (test-gatt.c:3182)
==20817==  Address 0x5a13908 is 8 bytes inside a block of size 40 free'd
==20817==    at 0x4C2A37C: free (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==20817==    by 0x140F1E: cancel_att_send_op (att.c:222)
==20817==    by 0x140F1E: bt_att_cancel (att.c:1200)
==20817==    by 0x145075: cancel_request (gatt-client.c:1852)
==20817==    by 0x14B902: queue_remove_all (queue.c:387)
==20817==    by 0x1457CC: bt_gatt_client_cancel_all (gatt-client.c:1866)
==20817==    by 0x145838: bt_gatt_client_free (gatt-client.c:1569)
==20817==    by 0x13D438: destroy_context (test-gatt.c:284)
==20817==    by 0x13D438: context_quit (test-gatt.c:312)
==20817==    by 0x14159A: handle_rsp (att.c:640)
==20817==    by 0x14159A: can_read_data (att.c:813)
==20817==    by 0x14AEC4: watch_callback (io-glib.c:170)
==20817==    by 0x4E808E4: g_main_context_dispatch (in /usr/lib64/libglib-2.0.so.0.4200.1)
==20817==    by 0x4E80C47: ??? (in /usr/lib64/libglib-2.0.so.0.4200.1)
==20817==    by 0x4E80F09: g_main_loop_run (in /usr/lib64/libglib-2.0.so.0.4200.1)
==20817== 
==20817== Invalid read of size 1
==20817==    at 0x14507C: cancel_request (gatt-client.c:1857)
==20817==    by 0x14B902: queue_remove_all (queue.c:387)
==20817==    by 0x1457CC: bt_gatt_client_cancel_all (gatt-client.c:1866)
==20817==    by 0x145838: bt_gatt_client_free (gatt-client.c:1569)
==20817==    by 0x13D438: destroy_context (test-gatt.c:284)
==20817==    by 0x13D438: context_quit (test-gatt.c:312)
==20817==    by 0x14159A: handle_rsp (att.c:640)
==20817==    by 0x14159A: can_read_data (att.c:813)
==20817==    by 0x14AEC4: watch_callback (io-glib.c:170)
==20817==    by 0x4E808E4: g_main_context_dispatch (in /usr/lib64/libglib-2.0.so.0.4200.1)
==20817==    by 0x4E80C47: ??? (in /usr/lib64/libglib-2.0.so.0.4200.1)
==20817==    by 0x4E80F09: g_main_loop_run (in /usr/lib64/libglib-2.0.so.0.4200.1)
==20817==    by 0x140030: tester_run (tester.c:830)
==20817==    by 0x13BE18: main (test-gatt.c:3182)
==20817==  Address 0x5a13909 is 9 bytes inside a block of size 40 free'd
==20817==    at 0x4C2A37C: free (in /usr/lib64/valgrind/vgpreload_memcheck-amd64-linux.so)
==20817==    by 0x140F1E: cancel_att_send_op (att.c:222)
==20817==    by 0x140F1E: bt_att_cancel (att.c:1200)
==20817==    by 0x145075: cancel_request (gatt-client.c:1852)
==20817==    by 0x14B902: queue_remove_all (queue.c:387)
==20817==    by 0x1457CC: bt_gatt_client_cancel_all (gatt-client.c:1866)
==20817==    by 0x145838: bt_gatt_client_free (gatt-client.c:1569)
==20817==    by 0x13D438: destroy_context (test-gatt.c:284)
==20817==    by 0x13D438: context_quit (test-gatt.c:312)
==20817==    by 0x14159A: handle_rsp (att.c:640)
==20817==    by 0x14159A: can_read_data (att.c:813)
==20817==    by 0x14AEC4: watch_callback (io-glib.c:170)
==20817==    by 0x4E808E4: g_main_context_dispatch (in /usr/lib64/libglib-2.0.so.0.4200.1)
==20817==    by 0x4E80C47: ??? (in /usr/lib64/libglib-2.0.so.0.4200.1)
==20817==    by 0x4E80F09: g_main_loop_run (in /usr/lib64/libglib-2.0.so.0.4200.1)
==20817== 
==20817== 
==20817== HEAP SUMMARY:
==20817==     in use at exit: 29,640 bytes in 618 blocks
==20817==   total heap usage: 36,545 allocs, 35,927 frees, 1,585,464 bytes allocated
==20817== 
==20817== LEAK SUMMARY:
==20817==    definitely lost: 0 bytes in 0 blocks
==20817==    indirectly lost: 0 bytes in 0 blocks
==20817==      possibly lost: 0 bytes in 0 blocks
==20817==    still reachable: 29,640 bytes in 618 blocks
==20817==         suppressed: 0 bytes in 0 blocks
==20817== Rerun with --leak-check=full to see details of leaked memory
==20817== 
==20817== For counts of detected and suppressed errors, rerun with: -v
==20817== Use --track-origins=yes to see where uninitialised values come from
==20817== ERROR SUMMARY: 358 errors from 4 contexts (suppressed: 0 from 0)

Unfortunately, my understanding of the code did not allow me
to fis this :-(

Best regards,

	Stefan
-- 
Stefan Seyfried
Linux Consultant & Developer -- GPG Key: 0x731B665B

B1 Systems GmbH
Osterfeldstraße 7 / 85088 Vohburg / http://www.b1-systems.de
GF: Ralph Dehner / Unternehmenssitz: Vohburg / AG: Ingolstadt,HRB 3537