* KASAN: use-after-free Read in bpf_tcp_close (2)
@ 2018-09-06 8:22 syzbot
2018-09-06 19:53 ` John Fastabend
0 siblings, 1 reply; 3+ messages in thread
From: syzbot @ 2018-09-06 8:22 UTC (permalink / raw)
To: ast, daniel, linux-kernel, netdev, syzkaller-bugs
Hello,
syzbot found the following crash on:
HEAD commit: 11f026b4e306 libbpf: Remove the duplicate checking of func..
git tree: bpf-next
console output: https://syzkaller.appspot.com/x/log.txt?x=153c55ca400000
kernel config: https://syzkaller.appspot.com/x/.config?x=4c7e83258d6e0156
dashboard link: https://syzkaller.appspot.com/bug?extid=579adfa56843da894bc5
compiler: gcc (GCC) 8.0.1 20180413 (experimental)
Unfortunately, I don't have any reproducer for this crash yet.
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+579adfa56843da894bc5@syzkaller.appspotmail.com
==================================================================
BUG: KASAN: use-after-free in atomic_read
include/asm-generic/atomic-instrumented.h:21 [inline]
BUG: KASAN: use-after-free in virt_spin_lock
arch/x86/include/asm/qspinlock.h:65 [inline]
BUG: KASAN: use-after-free in native_queued_spin_lock_slowpath+0x189/0x1220
kernel/locking/qspinlock.c:305
Read of size 4 at addr ffff8801bfd651a0 by task syz-executor1/9753
CPU: 1 PID: 9753 Comm: syz-executor1 Not tainted 4.19.0-rc2+ #89
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+0x1c9/0x2b4 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+0x242/0x30d 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_read+0x11/0x20 mm/kasan/kasan.c:272
atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
virt_spin_lock arch/x86/include/asm/qspinlock.h:65 [inline]
native_queued_spin_lock_slowpath+0x189/0x1220
kernel/locking/qspinlock.c:305
pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:679 [inline]
queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:32 [inline]
queued_spin_lock include/asm-generic/qspinlock.h:88 [inline]
do_raw_spin_lock+0x1a7/0x200 kernel/locking/spinlock_debug.c:113
__raw_spin_lock_bh include/linux/spinlock_api_smp.h:136 [inline]
_raw_spin_lock_bh+0x39/0x40 kernel/locking/spinlock.c:168
bpf_tcp_close+0x68e/0x10d0 kernel/bpf/sockmap.c:349
inet_release+0x104/0x1f0 net/ipv4/af_inet.c:428
inet6_release+0x50/0x70 net/ipv6/af_inet6.c:457
__sock_release+0xd7/0x250 net/socket.c:579
sock_close+0x19/0x20 net/socket.c:1139
__fput+0x38a/0xa40 fs/file_table.c:278
____fput+0x15/0x20 fs/file_table.c:309
task_work_run+0x1e8/0x2a0 kernel/task_work.c:113
tracehook_notify_resume include/linux/tracehook.h:193 [inline]
exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166
prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x410c51
Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 34 19 00 00 c3 48
83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48
89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00007ffeacb37d60 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000008 RCX: 0000000000410c51
RDX: 0000000000000000 RSI: 0000000000731f70 RDI: 0000000000000007
RBP: 0000000000000000 R08: ffffffffffffffff R09: ffffffffffffffff
R10: 00007ffeacb37c90 R11: 0000000000000293 R12: 0000000000000010
R13: 0000000000022aa9 R14: 000000000000004d R15: badc0ffeebadface
Allocated by task 9754:
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
kmem_cache_alloc_trace+0x152/0x730 mm/slab.c:3620
kmalloc include/linux/slab.h:513 [inline]
kzalloc include/linux/slab.h:707 [inline]
sock_map_alloc+0x209/0x430 kernel/bpf/sockmap.c:1653
find_and_alloc_map kernel/bpf/syscall.c:129 [inline]
map_create+0x3bd/0x1100 kernel/bpf/syscall.c:509
__do_sys_bpf kernel/bpf/syscall.c:2356 [inline]
__se_sys_bpf kernel/bpf/syscall.c:2333 [inline]
__x64_sys_bpf+0x303/0x510 kernel/bpf/syscall.c:2333
do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Freed by task 13:
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+0xd9/0x210 mm/slab.c:3813
sock_map_remove_complete kernel/bpf/sockmap.c:1561 [inline]
sock_map_free+0x428/0x570 kernel/bpf/sockmap.c:1756
bpf_map_free_deferred+0xba/0xf0 kernel/bpf/syscall.c:290
process_one_work+0xc73/0x1aa0 kernel/workqueue.c:2153
worker_thread+0x189/0x13c0 kernel/workqueue.c:2296
kthread+0x35a/0x420 kernel/kthread.c:246
ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413
The buggy address belongs to the object at ffff8801bfd65080
which belongs to the cache kmalloc-512 of size 512
The buggy address is located 288 bytes inside of
512-byte region [ffff8801bfd65080, ffff8801bfd65280)
The buggy address belongs to the page:
page:ffffea0006ff5940 count:1 mapcount:0 mapping:ffff8801dac00940
index:0xffff8801bfd65300
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffffea000702a488 ffffea00075c4148 ffff8801dac00940
raw: ffff8801bfd65300 ffff8801bfd65080 0000000100000001 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff8801bfd65080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8801bfd65100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ffff8801bfd65180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8801bfd65200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8801bfd65280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
---
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.
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: KASAN: use-after-free Read in bpf_tcp_close (2)
2018-09-06 8:22 KASAN: use-after-free Read in bpf_tcp_close (2) syzbot
@ 2018-09-06 19:53 ` John Fastabend
2019-03-23 7:24 ` Dmitry Vyukov
0 siblings, 1 reply; 3+ messages in thread
From: John Fastabend @ 2018-09-06 19:53 UTC (permalink / raw)
To: syzbot, ast, daniel, linux-kernel, netdev, syzkaller-bugs
On 09/06/2018 01:22 AM, syzbot wrote:
> Hello,
>
> syzbot found the following crash on:
>
> HEAD commit: 11f026b4e306 libbpf: Remove the duplicate checking of func..
> git tree: bpf-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=153c55ca400000
> kernel config: https://syzkaller.appspot.com/x/.config?x=4c7e83258d6e0156
> dashboard link: https://syzkaller.appspot.com/bug?extid=579adfa56843da894bc5
> compiler: gcc (GCC) 8.0.1 20180413 (experimental)
>
> Unfortunately, I don't have any reproducer for this crash yet.
>
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: syzbot+579adfa56843da894bc5@syzkaller.appspotmail.com
>
> ==================================================================
> BUG: KASAN: use-after-free in atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
> BUG: KASAN: use-after-free in virt_spin_lock arch/x86/include/asm/qspinlock.h:65 [inline]
> BUG: KASAN: use-after-free in native_queued_spin_lock_slowpath+0x189/0x1220 kernel/locking/qspinlock.c:305
> Read of size 4 at addr ffff8801bfd651a0 by task syz-executor1/9753
>
> CPU: 1 PID: 9753 Comm: syz-executor1 Not tainted 4.19.0-rc2+ #89
> 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+0x1c9/0x2b4 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+0x242/0x30d 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_read+0x11/0x20 mm/kasan/kasan.c:272
> atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
> virt_spin_lock arch/x86/include/asm/qspinlock.h:65 [inline]
> native_queued_spin_lock_slowpath+0x189/0x1220 kernel/locking/qspinlock.c:305
> pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:679 [inline]
> queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:32 [inline]
> queued_spin_lock include/asm-generic/qspinlock.h:88 [inline]
> do_raw_spin_lock+0x1a7/0x200 kernel/locking/spinlock_debug.c:113
> __raw_spin_lock_bh include/linux/spinlock_api_smp.h:136 [inline]
> _raw_spin_lock_bh+0x39/0x40 kernel/locking/spinlock.c:168
> bpf_tcp_close+0x68e/0x10d0 kernel/bpf/sockmap.c:349
> inet_release+0x104/0x1f0 net/ipv4/af_inet.c:428
> inet6_release+0x50/0x70 net/ipv6/af_inet6.c:457
> __sock_release+0xd7/0x250 net/socket.c:579
> sock_close+0x19/0x20 net/socket.c:1139
> __fput+0x38a/0xa40 fs/file_table.c:278
> ____fput+0x15/0x20 fs/file_table.c:309
> task_work_run+0x1e8/0x2a0 kernel/task_work.c:113
> tracehook_notify_resume include/linux/tracehook.h:193 [inline]
> exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166
> prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
> syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
> do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293
> entry_SYSCALL_64_after_hwframe+0x49/0xbe
> RIP: 0033:0x410c51
> Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 34 19 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01
> RSP: 002b:00007ffeacb37d60 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
> RAX: 0000000000000000 RBX: 0000000000000008 RCX: 0000000000410c51
> RDX: 0000000000000000 RSI: 0000000000731f70 RDI: 0000000000000007
> RBP: 0000000000000000 R08: ffffffffffffffff R09: ffffffffffffffff
> R10: 00007ffeacb37c90 R11: 0000000000000293 R12: 0000000000000010
> R13: 0000000000022aa9 R14: 000000000000004d R15: badc0ffeebadface
>
> Allocated by task 9754:
> 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
> kmem_cache_alloc_trace+0x152/0x730 mm/slab.c:3620
> kmalloc include/linux/slab.h:513 [inline]
> kzalloc include/linux/slab.h:707 [inline]
> sock_map_alloc+0x209/0x430 kernel/bpf/sockmap.c:1653
> find_and_alloc_map kernel/bpf/syscall.c:129 [inline]
> map_create+0x3bd/0x1100 kernel/bpf/syscall.c:509
> __do_sys_bpf kernel/bpf/syscall.c:2356 [inline]
> __se_sys_bpf kernel/bpf/syscall.c:2333 [inline]
> __x64_sys_bpf+0x303/0x510 kernel/bpf/syscall.c:2333
> do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
> entry_SYSCALL_64_after_hwframe+0x49/0xbe
>
> Freed by task 13:
> 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+0xd9/0x210 mm/slab.c:3813
> sock_map_remove_complete kernel/bpf/sockmap.c:1561 [inline]
> sock_map_free+0x428/0x570 kernel/bpf/sockmap.c:1756
> bpf_map_free_deferred+0xba/0xf0 kernel/bpf/syscall.c:290
> process_one_work+0xc73/0x1aa0 kernel/workqueue.c:2153
> worker_thread+0x189/0x13c0 kernel/workqueue.c:2296
> kthread+0x35a/0x420 kernel/kthread.c:246
> ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413
>
> The buggy address belongs to the object at ffff8801bfd65080
> which belongs to the cache kmalloc-512 of size 512
> The buggy address is located 288 bytes inside of
> 512-byte region [ffff8801bfd65080, ffff8801bfd65280)
> The buggy address belongs to the page:
> page:ffffea0006ff5940 count:1 mapcount:0 mapping:ffff8801dac00940 index:0xffff8801bfd65300
> flags: 0x2fffc0000000100(slab)
> raw: 02fffc0000000100 ffffea000702a488 ffffea00075c4148 ffff8801dac00940
> raw: ffff8801bfd65300 ffff8801bfd65080 0000000100000001 0000000000000000
> page dumped because: kasan: bad access detected
>
> Memory state around the buggy address:
> ffff8801bfd65080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ffff8801bfd65100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>> ffff8801bfd65180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ^
> ffff8801bfd65200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ffff8801bfd65280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> ==================================================================
>
>
> ---
> 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.
Introduced here (by a new reference to the map from the
tcp close context where a parallel free'ing of the map which
does not have a RCU grace period before free),
commit 585f5a6252ee43ec8feeee07387e3fcc7e8bb292
Author: Daniel Borkmann <daniel@iogearbox.net>
Date: Thu Aug 16 21:49:10 2018 +0200
bpf, sockmap: fix sock_map_ctx_update_elem race with exist/noexist
I'll have a fix shortly.
Thanks,
John
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: KASAN: use-after-free Read in bpf_tcp_close (2)
2018-09-06 19:53 ` John Fastabend
@ 2019-03-23 7:24 ` Dmitry Vyukov
0 siblings, 0 replies; 3+ messages in thread
From: Dmitry Vyukov @ 2019-03-23 7:24 UTC (permalink / raw)
To: John Fastabend
Cc: syzbot, Alexei Starovoitov, Daniel Borkmann, LKML, netdev,
syzkaller-bugs
On Thu, Sep 6, 2018 at 9:53 PM John Fastabend <john.fastabend@gmail.com> wrote:
>
> On 09/06/2018 01:22 AM, syzbot wrote:
> > Hello,
> >
> > syzbot found the following crash on:
> >
> > HEAD commit: 11f026b4e306 libbpf: Remove the duplicate checking of func..
> > git tree: bpf-next
> > console output: https://syzkaller.appspot.com/x/log.txt?x=153c55ca400000
> > kernel config: https://syzkaller.appspot.com/x/.config?x=4c7e83258d6e0156
> > dashboard link: https://syzkaller.appspot.com/bug?extid=579adfa56843da894bc5
> > compiler: gcc (GCC) 8.0.1 20180413 (experimental)
> >
> > Unfortunately, I don't have any reproducer for this crash yet.
> >
> > IMPORTANT: if you fix the bug, please add the following tag to the commit:
> > Reported-by: syzbot+579adfa56843da894bc5@syzkaller.appspotmail.com
> >
> > ==================================================================
> > BUG: KASAN: use-after-free in atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
> > BUG: KASAN: use-after-free in virt_spin_lock arch/x86/include/asm/qspinlock.h:65 [inline]
> > BUG: KASAN: use-after-free in native_queued_spin_lock_slowpath+0x189/0x1220 kernel/locking/qspinlock.c:305
> > Read of size 4 at addr ffff8801bfd651a0 by task syz-executor1/9753
> >
> > CPU: 1 PID: 9753 Comm: syz-executor1 Not tainted 4.19.0-rc2+ #89
> > 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+0x1c9/0x2b4 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+0x242/0x30d 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_read+0x11/0x20 mm/kasan/kasan.c:272
> > atomic_read include/asm-generic/atomic-instrumented.h:21 [inline]
> > virt_spin_lock arch/x86/include/asm/qspinlock.h:65 [inline]
> > native_queued_spin_lock_slowpath+0x189/0x1220 kernel/locking/qspinlock.c:305
> > pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:679 [inline]
> > queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:32 [inline]
> > queued_spin_lock include/asm-generic/qspinlock.h:88 [inline]
> > do_raw_spin_lock+0x1a7/0x200 kernel/locking/spinlock_debug.c:113
> > __raw_spin_lock_bh include/linux/spinlock_api_smp.h:136 [inline]
> > _raw_spin_lock_bh+0x39/0x40 kernel/locking/spinlock.c:168
> > bpf_tcp_close+0x68e/0x10d0 kernel/bpf/sockmap.c:349
> > inet_release+0x104/0x1f0 net/ipv4/af_inet.c:428
> > inet6_release+0x50/0x70 net/ipv6/af_inet6.c:457
> > __sock_release+0xd7/0x250 net/socket.c:579
> > sock_close+0x19/0x20 net/socket.c:1139
> > __fput+0x38a/0xa40 fs/file_table.c:278
> > ____fput+0x15/0x20 fs/file_table.c:309
> > task_work_run+0x1e8/0x2a0 kernel/task_work.c:113
> > tracehook_notify_resume include/linux/tracehook.h:193 [inline]
> > exit_to_usermode_loop+0x318/0x380 arch/x86/entry/common.c:166
> > prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
> > syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
> > do_syscall_64+0x6be/0x820 arch/x86/entry/common.c:293
> > entry_SYSCALL_64_after_hwframe+0x49/0xbe
> > RIP: 0033:0x410c51
> > Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 34 19 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01
> > RSP: 002b:00007ffeacb37d60 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
> > RAX: 0000000000000000 RBX: 0000000000000008 RCX: 0000000000410c51
> > RDX: 0000000000000000 RSI: 0000000000731f70 RDI: 0000000000000007
> > RBP: 0000000000000000 R08: ffffffffffffffff R09: ffffffffffffffff
> > R10: 00007ffeacb37c90 R11: 0000000000000293 R12: 0000000000000010
> > R13: 0000000000022aa9 R14: 000000000000004d R15: badc0ffeebadface
> >
> > Allocated by task 9754:
> > 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
> > kmem_cache_alloc_trace+0x152/0x730 mm/slab.c:3620
> > kmalloc include/linux/slab.h:513 [inline]
> > kzalloc include/linux/slab.h:707 [inline]
> > sock_map_alloc+0x209/0x430 kernel/bpf/sockmap.c:1653
> > find_and_alloc_map kernel/bpf/syscall.c:129 [inline]
> > map_create+0x3bd/0x1100 kernel/bpf/syscall.c:509
> > __do_sys_bpf kernel/bpf/syscall.c:2356 [inline]
> > __se_sys_bpf kernel/bpf/syscall.c:2333 [inline]
> > __x64_sys_bpf+0x303/0x510 kernel/bpf/syscall.c:2333
> > do_syscall_64+0x1b9/0x820 arch/x86/entry/common.c:290
> > entry_SYSCALL_64_after_hwframe+0x49/0xbe
> >
> > Freed by task 13:
> > 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+0xd9/0x210 mm/slab.c:3813
> > sock_map_remove_complete kernel/bpf/sockmap.c:1561 [inline]
> > sock_map_free+0x428/0x570 kernel/bpf/sockmap.c:1756
> > bpf_map_free_deferred+0xba/0xf0 kernel/bpf/syscall.c:290
> > process_one_work+0xc73/0x1aa0 kernel/workqueue.c:2153
> > worker_thread+0x189/0x13c0 kernel/workqueue.c:2296
> > kthread+0x35a/0x420 kernel/kthread.c:246
> > ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:413
> >
> > The buggy address belongs to the object at ffff8801bfd65080
> > which belongs to the cache kmalloc-512 of size 512
> > The buggy address is located 288 bytes inside of
> > 512-byte region [ffff8801bfd65080, ffff8801bfd65280)
> > The buggy address belongs to the page:
> > page:ffffea0006ff5940 count:1 mapcount:0 mapping:ffff8801dac00940 index:0xffff8801bfd65300
> > flags: 0x2fffc0000000100(slab)
> > raw: 02fffc0000000100 ffffea000702a488 ffffea00075c4148 ffff8801dac00940
> > raw: ffff8801bfd65300 ffff8801bfd65080 0000000100000001 0000000000000000
> > page dumped because: kasan: bad access detected
> >
> > Memory state around the buggy address:
> > ffff8801bfd65080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> > ffff8801bfd65100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> >> ffff8801bfd65180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> > ^
> > ffff8801bfd65200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> > ffff8801bfd65280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
> > ==================================================================
> >
> >
> > ---
> > 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.
>
> Introduced here (by a new reference to the map from the
> tcp close context where a parallel free'ing of the map which
> does not have a RCU grace period before free),
>
> commit 585f5a6252ee43ec8feeee07387e3fcc7e8bb292
> Author: Daniel Borkmann <daniel@iogearbox.net>
> Date: Thu Aug 16 21:49:10 2018 +0200
>
> bpf, sockmap: fix sock_map_ctx_update_elem race with exist/noexist
>
> I'll have a fix shortly.
>
> Thanks,
> John
John, did you fix it or not?
syzbot has closed it, so we may have lose this forever if not fixed.
If you fixed it, please include the Reported-by tag as asked by the reporter.
---------- Forwarded message ---------
From: syzbot <syzbot+579adfa56843da894bc5@syzkaller.appspotmail.com>
Date: Sat, Mar 23, 2019 at 5:55 AM
Subject: Re: KASAN: use-after-free Read in bpf_tcp_close (2)
To: <syzkaller-bugs@googlegroups.com>
Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2019-03-23 7:24 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-09-06 8:22 KASAN: use-after-free Read in bpf_tcp_close (2) syzbot
2018-09-06 19:53 ` John Fastabend
2019-03-23 7:24 ` Dmitry Vyukov
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.