LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
* KASAN: use-after-free Write in bpf_tcp_close
@ 2018-05-27 20:06 syzbot
  2018-05-27 22:15 ` Daniel Borkmann
  0 siblings, 1 reply; 4+ messages in thread
From: syzbot @ 2018-05-27 20:06 UTC (permalink / raw)
  To: ast, daniel, linux-kernel, netdev, syzkaller-bugs

Hello,

syzbot found the following crash on:

HEAD commit:    ff4fb475cea8 Merge branch 'btf-uapi-cleanups'
git tree:       bpf-next
console output: https://syzkaller.appspot.com/x/log.txt?x=12b3d577800000
kernel config:  https://syzkaller.appspot.com/x/.config?x=b632d8e2c2ab2c1
dashboard link: https://syzkaller.appspot.com/bug?extid=31025a5f3f7650081204
compiler:       gcc (GCC) 8.0.1 20180413 (experimental)
syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=109a2f37800000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=171a727b800000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+31025a5f3f7650081204@syzkaller.appspotmail.com

==================================================================
BUG: KASAN: use-after-free in cmpxchg_size  
include/asm-generic/atomic-instrumented.h:355 [inline]
BUG: KASAN: use-after-free in bpf_tcp_close+0x6f5/0xf80  
kernel/bpf/sockmap.c:265
Write of size 8 at addr ffff8801ca277680 by task syz-executor749/9723

CPU: 0 PID: 9723 Comm: syz-executor749 Not tainted 4.17.0-rc4+ #19
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
Call Trace:
  __dump_stack lib/dump_stack.c:77 [inline]
  dump_stack+0x1b9/0x294 lib/dump_stack.c:113
  print_address_description+0x6c/0x20b mm/kasan/report.c:256
  kasan_report_error mm/kasan/report.c:354 [inline]
  kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
  check_memory_region_inline mm/kasan/kasan.c:260 [inline]
  check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267
  kasan_check_write+0x14/0x20 mm/kasan/kasan.c:278
  cmpxchg_size include/asm-generic/atomic-instrumented.h:355 [inline]
  bpf_tcp_close+0x6f5/0xf80 kernel/bpf/sockmap.c:265
  inet_release+0x104/0x1f0 net/ipv4/af_inet.c:427
  inet6_release+0x50/0x70 net/ipv6/af_inet6.c:459
  sock_release+0x96/0x1b0 net/socket.c:594
  sock_close+0x16/0x20 net/socket.c:1149
  __fput+0x34d/0x890 fs/file_table.c:209
  ____fput+0x15/0x20 fs/file_table.c:243
  task_work_run+0x1e4/0x290 kernel/task_work.c:113
  exit_task_work include/linux/task_work.h:22 [inline]
  do_exit+0x1aee/0x2730 kernel/exit.c:865
  do_group_exit+0x16f/0x430 kernel/exit.c:968
  __do_sys_exit_group kernel/exit.c:979 [inline]
  __se_sys_exit_group kernel/exit.c:977 [inline]
  __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:977
  do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
  entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x440a59
RSP: 002b:00007ffdadf92488 EFLAGS: 00000206 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000440a59
RDX: 0000000000440a59 RSI: 0000000000000020 RDI: 0000000000000000
RBP: 0000000000000000 R08: 00000000004002c8 R09: 0000000000401ea0
R10: 00000000004002c8 R11: 0000000000000206 R12: 000000000001b5ac
R13: 0000000000401ea0 R14: 0000000000000000 R15: 0000000000000000

Allocated by task 9723:
  save_stack+0x43/0xd0 mm/kasan/kasan.c:448
  set_track mm/kasan/kasan.c:460 [inline]
  kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553
  __do_kmalloc_node mm/slab.c:3682 [inline]
  __kmalloc_node+0x47/0x70 mm/slab.c:3689
  kmalloc_node include/linux/slab.h:554 [inline]
  bpf_map_area_alloc+0x3f/0x90 kernel/bpf/syscall.c:144
  sock_map_alloc+0x376/0x410 kernel/bpf/sockmap.c:1555
  find_and_alloc_map kernel/bpf/syscall.c:126 [inline]
  map_create+0x393/0x1010 kernel/bpf/syscall.c:448
  __do_sys_bpf kernel/bpf/syscall.c:2128 [inline]
  __se_sys_bpf kernel/bpf/syscall.c:2105 [inline]
  __x64_sys_bpf+0x300/0x4f0 kernel/bpf/syscall.c:2105
  do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
  entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 4521:
  save_stack+0x43/0xd0 mm/kasan/kasan.c:448
  set_track mm/kasan/kasan.c:460 [inline]
  __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521
  kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
  __cache_free mm/slab.c:3498 [inline]
  kfree+0xd9/0x260 mm/slab.c:3813
  kvfree+0x61/0x70 mm/util.c:440
  bpf_map_area_free+0x15/0x20 kernel/bpf/syscall.c:155
  sock_map_remove_complete kernel/bpf/sockmap.c:1443 [inline]
  sock_map_free+0x408/0x540 kernel/bpf/sockmap.c:1619
  bpf_map_free_deferred+0xba/0xf0 kernel/bpf/syscall.c:259
  process_one_work+0xc1e/0x1b50 kernel/workqueue.c:2145
  worker_thread+0x1cc/0x1440 kernel/workqueue.c:2279
  kthread+0x345/0x410 kernel/kthread.c:238
  ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412

The buggy address belongs to the object at ffff8801ca277680
  which belongs to the cache kmalloc-1024 of size 1024
The buggy address is located 0 bytes inside of
  1024-byte region [ffff8801ca277680, ffff8801ca277a80)
The buggy address belongs to the page:
page:ffffea0007289d80 count:1 mapcount:0 mapping:ffff8801ca276000 index:0x0  
compound_mapcount: 0
flags: 0x2fffc0000008100(slab|head)
raw: 02fffc0000008100 ffff8801ca276000 0000000000000000 0000000100000007
raw: ffffea0006d12b20 ffffea000763bba0 ffff8801da800ac0 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
  ffff8801ca277580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
  ffff8801ca277600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> ffff8801ca277680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                    ^
  ffff8801ca277700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
  ffff8801ca277780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


---
This bug is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@googlegroups.com.

syzbot will keep track of this bug report. See:
https://goo.gl/tpsmEJ#bug-status-tracking for how to communicate with  
syzbot.
syzbot can test patches for this bug, for details see:
https://goo.gl/tpsmEJ#testing-patches

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: KASAN: use-after-free Write in bpf_tcp_close
  2018-05-27 20:06 KASAN: use-after-free Write in bpf_tcp_close syzbot
@ 2018-05-27 22:15 ` Daniel Borkmann
  2018-06-07 16:58   ` Dmitry Vyukov
  0 siblings, 1 reply; 4+ messages in thread
From: Daniel Borkmann @ 2018-05-27 22:15 UTC (permalink / raw)
  To: syzbot, ast, linux-kernel, netdev, syzkaller-bugs, john.fastabend

[ +John ]

On 05/27/2018 10:06 PM, syzbot wrote:
> Hello,
> 
> syzbot found the following crash on:
> 
> HEAD commit:    ff4fb475cea8 Merge branch 'btf-uapi-cleanups'
> git tree:       bpf-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=12b3d577800000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=b632d8e2c2ab2c1
> dashboard link: https://syzkaller.appspot.com/bug?extid=31025a5f3f7650081204
> compiler:       gcc (GCC) 8.0.1 20180413 (experimental)
> syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=109a2f37800000
> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=171a727b800000
> 
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+31025a5f3f7650081204@syzkaller.appspotmail.com

Should be fixed by: https://patchwork.ozlabs.org/patch/920695/

> ==================================================================
> BUG: KASAN: use-after-free in cmpxchg_size include/asm-generic/atomic-instrumented.h:355 [inline]
> BUG: KASAN: use-after-free in bpf_tcp_close+0x6f5/0xf80 kernel/bpf/sockmap.c:265
> Write of size 8 at addr ffff8801ca277680 by task syz-executor749/9723
> 
> CPU: 0 PID: 9723 Comm: syz-executor749 Not tainted 4.17.0-rc4+ #19
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
> Call Trace:
>  __dump_stack lib/dump_stack.c:77 [inline]
>  dump_stack+0x1b9/0x294 lib/dump_stack.c:113
>  print_address_description+0x6c/0x20b mm/kasan/report.c:256
>  kasan_report_error mm/kasan/report.c:354 [inline]
>  kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
>  check_memory_region_inline mm/kasan/kasan.c:260 [inline]
>  check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267
>  kasan_check_write+0x14/0x20 mm/kasan/kasan.c:278
>  cmpxchg_size include/asm-generic/atomic-instrumented.h:355 [inline]
>  bpf_tcp_close+0x6f5/0xf80 kernel/bpf/sockmap.c:265
>  inet_release+0x104/0x1f0 net/ipv4/af_inet.c:427
>  inet6_release+0x50/0x70 net/ipv6/af_inet6.c:459
>  sock_release+0x96/0x1b0 net/socket.c:594
>  sock_close+0x16/0x20 net/socket.c:1149
>  __fput+0x34d/0x890 fs/file_table.c:209
>  ____fput+0x15/0x20 fs/file_table.c:243
>  task_work_run+0x1e4/0x290 kernel/task_work.c:113
>  exit_task_work include/linux/task_work.h:22 [inline]
>  do_exit+0x1aee/0x2730 kernel/exit.c:865
>  do_group_exit+0x16f/0x430 kernel/exit.c:968
>  __do_sys_exit_group kernel/exit.c:979 [inline]
>  __se_sys_exit_group kernel/exit.c:977 [inline]
>  __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:977
>  do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
>  entry_SYSCALL_64_after_hwframe+0x49/0xbe
> RIP: 0033:0x440a59
> RSP: 002b:00007ffdadf92488 EFLAGS: 00000206 ORIG_RAX: 00000000000000e7
> RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000440a59
> RDX: 0000000000440a59 RSI: 0000000000000020 RDI: 0000000000000000
> RBP: 0000000000000000 R08: 00000000004002c8 R09: 0000000000401ea0
> R10: 00000000004002c8 R11: 0000000000000206 R12: 000000000001b5ac
> R13: 0000000000401ea0 R14: 0000000000000000 R15: 0000000000000000
> 
> Allocated by task 9723:
>  save_stack+0x43/0xd0 mm/kasan/kasan.c:448
>  set_track mm/kasan/kasan.c:460 [inline]
>  kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553
>  __do_kmalloc_node mm/slab.c:3682 [inline]
>  __kmalloc_node+0x47/0x70 mm/slab.c:3689
>  kmalloc_node include/linux/slab.h:554 [inline]
>  bpf_map_area_alloc+0x3f/0x90 kernel/bpf/syscall.c:144
>  sock_map_alloc+0x376/0x410 kernel/bpf/sockmap.c:1555
>  find_and_alloc_map kernel/bpf/syscall.c:126 [inline]
>  map_create+0x393/0x1010 kernel/bpf/syscall.c:448
>  __do_sys_bpf kernel/bpf/syscall.c:2128 [inline]
>  __se_sys_bpf kernel/bpf/syscall.c:2105 [inline]
>  __x64_sys_bpf+0x300/0x4f0 kernel/bpf/syscall.c:2105
>  do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
>  entry_SYSCALL_64_after_hwframe+0x49/0xbe
> 
> Freed by task 4521:
>  save_stack+0x43/0xd0 mm/kasan/kasan.c:448
>  set_track mm/kasan/kasan.c:460 [inline]
>  __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521
>  kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
>  __cache_free mm/slab.c:3498 [inline]
>  kfree+0xd9/0x260 mm/slab.c:3813
>  kvfree+0x61/0x70 mm/util.c:440
>  bpf_map_area_free+0x15/0x20 kernel/bpf/syscall.c:155
>  sock_map_remove_complete kernel/bpf/sockmap.c:1443 [inline]
>  sock_map_free+0x408/0x540 kernel/bpf/sockmap.c:1619
>  bpf_map_free_deferred+0xba/0xf0 kernel/bpf/syscall.c:259
>  process_one_work+0xc1e/0x1b50 kernel/workqueue.c:2145
>  worker_thread+0x1cc/0x1440 kernel/workqueue.c:2279
>  kthread+0x345/0x410 kernel/kthread.c:238
>  ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412
> 
> The buggy address belongs to the object at ffff8801ca277680
>  which belongs to the cache kmalloc-1024 of size 1024
> The buggy address is located 0 bytes inside of
>  1024-byte region [ffff8801ca277680, ffff8801ca277a80)
> The buggy address belongs to the page:
> page:ffffea0007289d80 count:1 mapcount:0 mapping:ffff8801ca276000 index:0x0 compound_mapcount: 0
> flags: 0x2fffc0000008100(slab|head)
> raw: 02fffc0000008100 ffff8801ca276000 0000000000000000 0000000100000007
> raw: ffffea0006d12b20 ffffea000763bba0 ffff8801da800ac0 0000000000000000
> page dumped because: kasan: bad access detected
> 
> Memory state around the buggy address:
>  ffff8801ca277580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>  ffff8801ca277600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>> ffff8801ca277680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>                    ^
>  ffff8801ca277700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>  ffff8801ca277780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ==================================================================
> 
> 
> ---
> This bug is generated by a bot. It may contain errors.
> See https://goo.gl/tpsmEJ for more information about syzbot.
> syzbot engineers can be reached at syzkaller@googlegroups.com.
> 
> syzbot will keep track of this bug report. See:
> https://goo.gl/tpsmEJ#bug-status-tracking for how to communicate with syzbot.
> syzbot can test patches for this bug, for details see:
> https://goo.gl/tpsmEJ#testing-patches

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: KASAN: use-after-free Write in bpf_tcp_close
  2018-05-27 22:15 ` Daniel Borkmann
@ 2018-06-07 16:58   ` Dmitry Vyukov
  2018-06-08 16:03     ` John Fastabend
  0 siblings, 1 reply; 4+ messages in thread
From: Dmitry Vyukov @ 2018-06-07 16:58 UTC (permalink / raw)
  To: Daniel Borkmann
  Cc: syzbot, Alexei Starovoitov, LKML, netdev, syzkaller-bugs, John Fastabend

On Mon, May 28, 2018 at 12:15 AM, Daniel Borkmann <daniel@iogearbox.net> wrote:
> [ +John ]
>
> On 05/27/2018 10:06 PM, syzbot wrote:
>> Hello,
>>
>> syzbot found the following crash on:
>>
>> HEAD commit:    ff4fb475cea8 Merge branch 'btf-uapi-cleanups'
>> git tree:       bpf-next
>> console output: https://syzkaller.appspot.com/x/log.txt?x=12b3d577800000
>> kernel config:  https://syzkaller.appspot.com/x/.config?x=b632d8e2c2ab2c1
>> dashboard link: https://syzkaller.appspot.com/bug?extid=31025a5f3f7650081204
>> compiler:       gcc (GCC) 8.0.1 20180413 (experimental)
>> syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=109a2f37800000
>> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=171a727b800000
>>
>> IMPORTANT: if you fix the bug, please add the following tag to the commit:
>> Reported-by: syzbot+31025a5f3f7650081204@syzkaller.appspotmail.com
>
> Should be fixed by: https://patchwork.ozlabs.org/patch/920695/

#syz fix: bpf: sockhash fix race with bpf_tcp_close and map delete

>> ==================================================================
>> BUG: KASAN: use-after-free in cmpxchg_size include/asm-generic/atomic-instrumented.h:355 [inline]
>> BUG: KASAN: use-after-free in bpf_tcp_close+0x6f5/0xf80 kernel/bpf/sockmap.c:265
>> Write of size 8 at addr ffff8801ca277680 by task syz-executor749/9723
>>
>> CPU: 0 PID: 9723 Comm: syz-executor749 Not tainted 4.17.0-rc4+ #19
>> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
>> Call Trace:
>>  __dump_stack lib/dump_stack.c:77 [inline]
>>  dump_stack+0x1b9/0x294 lib/dump_stack.c:113
>>  print_address_description+0x6c/0x20b mm/kasan/report.c:256
>>  kasan_report_error mm/kasan/report.c:354 [inline]
>>  kasan_report.cold.7+0x242/0x2fe mm/kasan/report.c:412
>>  check_memory_region_inline mm/kasan/kasan.c:260 [inline]
>>  check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267
>>  kasan_check_write+0x14/0x20 mm/kasan/kasan.c:278
>>  cmpxchg_size include/asm-generic/atomic-instrumented.h:355 [inline]
>>  bpf_tcp_close+0x6f5/0xf80 kernel/bpf/sockmap.c:265
>>  inet_release+0x104/0x1f0 net/ipv4/af_inet.c:427
>>  inet6_release+0x50/0x70 net/ipv6/af_inet6.c:459
>>  sock_release+0x96/0x1b0 net/socket.c:594
>>  sock_close+0x16/0x20 net/socket.c:1149
>>  __fput+0x34d/0x890 fs/file_table.c:209
>>  ____fput+0x15/0x20 fs/file_table.c:243
>>  task_work_run+0x1e4/0x290 kernel/task_work.c:113
>>  exit_task_work include/linux/task_work.h:22 [inline]
>>  do_exit+0x1aee/0x2730 kernel/exit.c:865
>>  do_group_exit+0x16f/0x430 kernel/exit.c:968
>>  __do_sys_exit_group kernel/exit.c:979 [inline]
>>  __se_sys_exit_group kernel/exit.c:977 [inline]
>>  __x64_sys_exit_group+0x3e/0x50 kernel/exit.c:977
>>  do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
>>  entry_SYSCALL_64_after_hwframe+0x49/0xbe
>> RIP: 0033:0x440a59
>> RSP: 002b:00007ffdadf92488 EFLAGS: 00000206 ORIG_RAX: 00000000000000e7
>> RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000440a59
>> RDX: 0000000000440a59 RSI: 0000000000000020 RDI: 0000000000000000
>> RBP: 0000000000000000 R08: 00000000004002c8 R09: 0000000000401ea0
>> R10: 00000000004002c8 R11: 0000000000000206 R12: 000000000001b5ac
>> R13: 0000000000401ea0 R14: 0000000000000000 R15: 0000000000000000
>>
>> Allocated by task 9723:
>>  save_stack+0x43/0xd0 mm/kasan/kasan.c:448
>>  set_track mm/kasan/kasan.c:460 [inline]
>>  kasan_kmalloc+0xc4/0xe0 mm/kasan/kasan.c:553
>>  __do_kmalloc_node mm/slab.c:3682 [inline]
>>  __kmalloc_node+0x47/0x70 mm/slab.c:3689
>>  kmalloc_node include/linux/slab.h:554 [inline]
>>  bpf_map_area_alloc+0x3f/0x90 kernel/bpf/syscall.c:144
>>  sock_map_alloc+0x376/0x410 kernel/bpf/sockmap.c:1555
>>  find_and_alloc_map kernel/bpf/syscall.c:126 [inline]
>>  map_create+0x393/0x1010 kernel/bpf/syscall.c:448
>>  __do_sys_bpf kernel/bpf/syscall.c:2128 [inline]
>>  __se_sys_bpf kernel/bpf/syscall.c:2105 [inline]
>>  __x64_sys_bpf+0x300/0x4f0 kernel/bpf/syscall.c:2105
>>  do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
>>  entry_SYSCALL_64_after_hwframe+0x49/0xbe
>>
>> Freed by task 4521:
>>  save_stack+0x43/0xd0 mm/kasan/kasan.c:448
>>  set_track mm/kasan/kasan.c:460 [inline]
>>  __kasan_slab_free+0x11a/0x170 mm/kasan/kasan.c:521
>>  kasan_slab_free+0xe/0x10 mm/kasan/kasan.c:528
>>  __cache_free mm/slab.c:3498 [inline]
>>  kfree+0xd9/0x260 mm/slab.c:3813
>>  kvfree+0x61/0x70 mm/util.c:440
>>  bpf_map_area_free+0x15/0x20 kernel/bpf/syscall.c:155
>>  sock_map_remove_complete kernel/bpf/sockmap.c:1443 [inline]
>>  sock_map_free+0x408/0x540 kernel/bpf/sockmap.c:1619
>>  bpf_map_free_deferred+0xba/0xf0 kernel/bpf/syscall.c:259
>>  process_one_work+0xc1e/0x1b50 kernel/workqueue.c:2145
>>  worker_thread+0x1cc/0x1440 kernel/workqueue.c:2279
>>  kthread+0x345/0x410 kernel/kthread.c:238
>>  ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:412
>>
>> The buggy address belongs to the object at ffff8801ca277680
>>  which belongs to the cache kmalloc-1024 of size 1024
>> The buggy address is located 0 bytes inside of
>>  1024-byte region [ffff8801ca277680, ffff8801ca277a80)
>> The buggy address belongs to the page:
>> page:ffffea0007289d80 count:1 mapcount:0 mapping:ffff8801ca276000 index:0x0 compound_mapcount: 0
>> flags: 0x2fffc0000008100(slab|head)
>> raw: 02fffc0000008100 ffff8801ca276000 0000000000000000 0000000100000007
>> raw: ffffea0006d12b20 ffffea000763bba0 ffff8801da800ac0 0000000000000000
>> page dumped because: kasan: bad access detected
>>
>> Memory state around the buggy address:
>>  ffff8801ca277580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>>  ffff8801ca277600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>>> ffff8801ca277680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>>                    ^
>>  ffff8801ca277700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>>  ffff8801ca277780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>> ==================================================================
>>
>>
>> ---
>> This bug is generated by a bot. It may contain errors.
>> See https://goo.gl/tpsmEJ for more information about syzbot.
>> syzbot engineers can be reached at syzkaller@googlegroups.com.
>>
>> syzbot will keep track of this bug report. See:
>> https://goo.gl/tpsmEJ#bug-status-tracking for how to communicate with syzbot.
>> syzbot can test patches for this bug, for details see:
>> https://goo.gl/tpsmEJ#testing-patches
>
> --
> You received this message because you are subscribed to the Google Groups "syzkaller-bugs" group.
> To unsubscribe from this group and stop receiving emails from it, send an email to syzkaller-bugs+unsubscribe@googlegroups.com.
> To view this discussion on the web visit https://groups.google.com/d/msgid/syzkaller-bugs/ca3eff64-adb0-6110-38ca-2e07b6ecc3d6%40iogearbox.net.
> For more options, visit https://groups.google.com/d/optout.

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: KASAN: use-after-free Write in bpf_tcp_close
  2018-06-07 16:58   ` Dmitry Vyukov
@ 2018-06-08 16:03     ` John Fastabend
  0 siblings, 0 replies; 4+ messages in thread
From: John Fastabend @ 2018-06-08 16:03 UTC (permalink / raw)
  To: Dmitry Vyukov, Daniel Borkmann
  Cc: syzbot, Alexei Starovoitov, LKML, netdev, syzkaller-bugs

On 06/07/2018 09:58 AM, Dmitry Vyukov wrote:
> On Mon, May 28, 2018 at 12:15 AM, Daniel Borkmann <daniel@iogearbox.net> wrote:
>> [ +John ]
>>
>> On 05/27/2018 10:06 PM, syzbot wrote:
>>> Hello,
>>>
>>> syzbot found the following crash on:
>>>
>>> HEAD commit:    ff4fb475cea8 Merge branch 'btf-uapi-cleanups'
>>> git tree:       bpf-next
>>> console output: https://syzkaller.appspot.com/x/log.txt?x=12b3d577800000
>>> kernel config:  https://syzkaller.appspot.com/x/.config?x=b632d8e2c2ab2c1
>>> dashboard link: https://syzkaller.appspot.com/bug?extid=31025a5f3f7650081204
>>> compiler:       gcc (GCC) 8.0.1 20180413 (experimental)
>>> syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=109a2f37800000
>>> C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=171a727b800000
>>>
>>> IMPORTANT: if you fix the bug, please add the following tag to the commit:
>>> Reported-by: syzbot+31025a5f3f7650081204@syzkaller.appspotmail.com
>>
>> Should be fixed by: https://patchwork.ozlabs.org/patch/920695/
> 
> #syz fix: bpf: sockhash fix race with bpf_tcp_close and map delete
> 

Same here 'bpf: sockhash fix race with bpf_tcp_close and map delete"
was dropped and a new fix will be posted shortly.

Thanks!
John

^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2018-06-08 16:03 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-05-27 20:06 KASAN: use-after-free Write in bpf_tcp_close syzbot
2018-05-27 22:15 ` Daniel Borkmann
2018-06-07 16:58   ` Dmitry Vyukov
2018-06-08 16:03     ` John Fastabend

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).