* WARNING in bpf_cgroup_link_release
@ 2020-04-15 6:55 syzbot
2020-04-15 11:57 ` Daniel Borkmann
2020-09-01 2:58 ` syzbot
0 siblings, 2 replies; 6+ messages in thread
From: syzbot @ 2020-04-15 6:55 UTC (permalink / raw)
To: andriin, ast, bpf, daniel, john.fastabend, kafai, kpsingh,
linux-kernel, netdev, songliubraving, syzkaller-bugs, yhs
Hello,
syzbot found the following crash on:
HEAD commit: 1a323ea5 x86: get rid of 'errret' argument to __get_user_x..
git tree: bpf-next
console output: https://syzkaller.appspot.com/x/log.txt?x=148ccb57e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=8c1e98458335a7d1
dashboard link: https://syzkaller.appspot.com/bug?extid=8a5dadc5c0b1d7055945
compiler: gcc (GCC) 9.0.0 20181231 (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+8a5dadc5c0b1d7055945@syzkaller.appspotmail.com
------------[ cut here ]------------
WARNING: CPU: 0 PID: 25081 at kernel/bpf/cgroup.c:796 bpf_cgroup_link_release+0x260/0x3a0 kernel/bpf/cgroup.c:796
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 25081 Comm: syz-executor.1 Not tainted 5.6.0-syzkaller #0
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+0x188/0x20d lib/dump_stack.c:118
panic+0x2e3/0x75c kernel/panic.c:221
__warn.cold+0x2f/0x35 kernel/panic.c:582
report_bug+0x27b/0x2f0 lib/bug.c:195
fixup_bug arch/x86/kernel/traps.c:175 [inline]
fixup_bug arch/x86/kernel/traps.c:170 [inline]
do_error_trap+0x12b/0x220 arch/x86/kernel/traps.c:267
do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:286
invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027
RIP: 0010:bpf_cgroup_link_release+0x260/0x3a0 kernel/bpf/cgroup.c:796
Code: cf ff 5b 5d 41 5c e9 df 2a e9 ff e8 da 2a e9 ff 48 c7 c7 20 f4 9d 89 e8 de a0 3a 06 5b 5d 41 5c e9 c5 2a e9 ff e8 c0 2a e9 ff <0f> 0b e9 57 fe ff ff e8 a4 3d 26 00 e9 2a fe ff ff e8 9a 3d 26 00
RSP: 0018:ffffc900019a7dc0 EFLAGS: 00010246
RAX: 0000000000040000 RBX: ffff88808c3eac00 RCX: ffffc9000415a000
RDX: 0000000000040000 RSI: ffffffff8189bea0 RDI: 0000000000000005
RBP: 00000000fffffff4 R08: ffff88809055e000 R09: ffffed1015cc70f4
R10: ffffed1015cc70f3 R11: ffff8880ae63879b R12: ffff88808c3eac60
R13: ffff88808c3eac10 R14: ffffc90000f32000 R15: ffffffff817f8e60
bpf_link_free+0x80/0x140 kernel/bpf/syscall.c:2217
bpf_link_put+0x15e/0x1b0 kernel/bpf/syscall.c:2243
bpf_link_release+0x33/0x40 kernel/bpf/syscall.c:2251
__fput+0x2e9/0x860 fs/file_table.c:280
task_work_run+0xf4/0x1b0 kernel/task_work.c:123
tracehook_notify_resume include/linux/tracehook.h:188 [inline]
exit_to_usermode_loop+0x2fa/0x360 arch/x86/entry/common.c:165
prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
syscall_return_slowpath arch/x86/entry/common.c:279 [inline]
do_syscall_64+0x6b1/0x7d0 arch/x86/entry/common.c:305
entry_SYSCALL_64_after_hwframe+0x49/0xb3
RIP: 0033:0x45c889
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007fddaf43fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 00007fddaf4406d4 RCX: 000000000045c889
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006
R13: 0000000000000078 R14: 00000000005043d2 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..
---
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#status for how to communicate with syzbot.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: WARNING in bpf_cgroup_link_release
2020-04-15 6:55 WARNING in bpf_cgroup_link_release syzbot
@ 2020-04-15 11:57 ` Daniel Borkmann
2020-04-15 16:51 ` Andrii Nakryiko
2020-09-01 2:58 ` syzbot
1 sibling, 1 reply; 6+ messages in thread
From: Daniel Borkmann @ 2020-04-15 11:57 UTC (permalink / raw)
To: syzbot, andriin, ast, bpf, john.fastabend, kafai, kpsingh,
linux-kernel, netdev, songliubraving, syzkaller-bugs, yhs
On 4/15/20 8:55 AM, syzbot wrote:
> Hello,
>
> syzbot found the following crash on:
Andrii, ptal.
> HEAD commit: 1a323ea5 x86: get rid of 'errret' argument to __get_user_x..
> git tree: bpf-next
> console output: https://syzkaller.appspot.com/x/log.txt?x=148ccb57e00000
> kernel config: https://syzkaller.appspot.com/x/.config?x=8c1e98458335a7d1
> dashboard link: https://syzkaller.appspot.com/bug?extid=8a5dadc5c0b1d7055945
> compiler: gcc (GCC) 9.0.0 20181231 (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+8a5dadc5c0b1d7055945@syzkaller.appspotmail.com
>
> ------------[ cut here ]------------
> WARNING: CPU: 0 PID: 25081 at kernel/bpf/cgroup.c:796 bpf_cgroup_link_release+0x260/0x3a0 kernel/bpf/cgroup.c:796
> Kernel panic - not syncing: panic_on_warn set ...
> CPU: 0 PID: 25081 Comm: syz-executor.1 Not tainted 5.6.0-syzkaller #0
> 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+0x188/0x20d lib/dump_stack.c:118
> panic+0x2e3/0x75c kernel/panic.c:221
> __warn.cold+0x2f/0x35 kernel/panic.c:582
> report_bug+0x27b/0x2f0 lib/bug.c:195
> fixup_bug arch/x86/kernel/traps.c:175 [inline]
> fixup_bug arch/x86/kernel/traps.c:170 [inline]
> do_error_trap+0x12b/0x220 arch/x86/kernel/traps.c:267
> do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:286
> invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027
> RIP: 0010:bpf_cgroup_link_release+0x260/0x3a0 kernel/bpf/cgroup.c:796
> Code: cf ff 5b 5d 41 5c e9 df 2a e9 ff e8 da 2a e9 ff 48 c7 c7 20 f4 9d 89 e8 de a0 3a 06 5b 5d 41 5c e9 c5 2a e9 ff e8 c0 2a e9 ff <0f> 0b e9 57 fe ff ff e8 a4 3d 26 00 e9 2a fe ff ff e8 9a 3d 26 00
> RSP: 0018:ffffc900019a7dc0 EFLAGS: 00010246
> RAX: 0000000000040000 RBX: ffff88808c3eac00 RCX: ffffc9000415a000
> RDX: 0000000000040000 RSI: ffffffff8189bea0 RDI: 0000000000000005
> RBP: 00000000fffffff4 R08: ffff88809055e000 R09: ffffed1015cc70f4
> R10: ffffed1015cc70f3 R11: ffff8880ae63879b R12: ffff88808c3eac60
> R13: ffff88808c3eac10 R14: ffffc90000f32000 R15: ffffffff817f8e60
> bpf_link_free+0x80/0x140 kernel/bpf/syscall.c:2217
> bpf_link_put+0x15e/0x1b0 kernel/bpf/syscall.c:2243
> bpf_link_release+0x33/0x40 kernel/bpf/syscall.c:2251
> __fput+0x2e9/0x860 fs/file_table.c:280
> task_work_run+0xf4/0x1b0 kernel/task_work.c:123
> tracehook_notify_resume include/linux/tracehook.h:188 [inline]
> exit_to_usermode_loop+0x2fa/0x360 arch/x86/entry/common.c:165
> prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
> syscall_return_slowpath arch/x86/entry/common.c:279 [inline]
> do_syscall_64+0x6b1/0x7d0 arch/x86/entry/common.c:305
> entry_SYSCALL_64_after_hwframe+0x49/0xb3
> RIP: 0033:0x45c889
> Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
> RSP: 002b:00007fddaf43fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
> RAX: 0000000000000000 RBX: 00007fddaf4406d4 RCX: 000000000045c889
> RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005
> RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006
> R13: 0000000000000078 R14: 00000000005043d2 R15: 0000000000000000
> Kernel Offset: disabled
> Rebooting in 86400 seconds..
>
>
> ---
> 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#status for how to communicate with syzbot.
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: WARNING in bpf_cgroup_link_release
2020-04-15 11:57 ` Daniel Borkmann
@ 2020-04-15 16:51 ` Andrii Nakryiko
2020-04-16 10:26 ` Dan Carpenter
0 siblings, 1 reply; 6+ messages in thread
From: Andrii Nakryiko @ 2020-04-15 16:51 UTC (permalink / raw)
To: Daniel Borkmann, syzbot, ast, bpf, john.fastabend, kafai,
kpsingh, linux-kernel, netdev, songliubraving, syzkaller-bugs,
yhs
On 4/15/20 4:57 AM, Daniel Borkmann wrote:
> On 4/15/20 8:55 AM, syzbot wrote:
>> Hello,
>>
>> syzbot found the following crash on:
>
> Andrii, ptal.
>
>> HEAD commit: 1a323ea5 x86: get rid of 'errret' argument to
>> __get_user_x..
>> git tree: bpf-next
>> console output:
>> https://urldefense.proofpoint.com/v2/url?u=https-3A__syzkaller.appspot.com_x_log.txt-3Fx-3D148ccb57e00000&d=DwICaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=vxqvl81C2rT6GOGdPyz8iQ&m=T2Ez0XmyIpHmEa_MPTTUOh61jMDXqwETtTaTbSe-2M4&s=-6XBbsNV1O4X5flrx4Yssfjc56d0qeSHgwHhd92UPJc&e=
>> kernel config:
>> https://urldefense.proofpoint.com/v2/url?u=https-3A__syzkaller.appspot.com_x_.config-3Fx-3D8c1e98458335a7d1&d=DwICaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=vxqvl81C2rT6GOGdPyz8iQ&m=T2Ez0XmyIpHmEa_MPTTUOh61jMDXqwETtTaTbSe-2M4&s=s5-1AlWtSiBvo66WN4_UXoXMGIGIqsoUCrmAnxNnfX0&e=
>> dashboard link:
>> https://urldefense.proofpoint.com/v2/url?u=https-3A__syzkaller.appspot.com_bug-3Fextid-3D8a5dadc5c0b1d7055945&d=DwICaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=vxqvl81C2rT6GOGdPyz8iQ&m=T2Ez0XmyIpHmEa_MPTTUOh61jMDXqwETtTaTbSe-2M4&s=hAA0702qJH5EwRwvG0RKmj8FwIRm1O8hvmoS7ne5Dls&e=
>> compiler: gcc (GCC) 9.0.0 20181231 (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+8a5dadc5c0b1d7055945@syzkaller.appspotmail.com
>>
>> ------------[ cut here ]------------
>> WARNING: CPU: 0 PID: 25081 at kernel/bpf/cgroup.c:796
>> bpf_cgroup_link_release+0x260/0x3a0 kernel/bpf/cgroup.c:796
This warning is triggered due to __cgroup_bpf_detach returning an error.
It can do it only in two cases: either attached item is not found, which
from starting at code some moreI don't see how that can happen. The
other reason - kmalloc() failing to allocate memory for new effective
prog array. The latter is a bit annoying behavior of cgroup detach, and
I wonder if it makes sense to actually make that operation non-failing
by replacing detached program with dummy noop program. Or at least do it
if allocating new effective prog array fails. This wasn't previously
triggered, because when user explicitly detaches and that fails, we'd be
just returning this to user-space, but for links we have WARN_ON,
because we have no way to propagate error back, because there is little
user can do about that.
So, should we change detach to be non-failing (assuming program to be
detached is found?)
>> Kernel panic - not syncing: panic_on_warn set ...
>> CPU: 0 PID: 25081 Comm: syz-executor.1 Not tainted 5.6.0-syzkaller #0
>> 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+0x188/0x20d lib/dump_stack.c:118
>> panic+0x2e3/0x75c kernel/panic.c:221
>> __warn.cold+0x2f/0x35 kernel/panic.c:582
>> report_bug+0x27b/0x2f0 lib/bug.c:195
>> fixup_bug arch/x86/kernel/traps.c:175 [inline]
>> fixup_bug arch/x86/kernel/traps.c:170 [inline]
>> do_error_trap+0x12b/0x220 arch/x86/kernel/traps.c:267
>> do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:286
>> invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1027
>> RIP: 0010:bpf_cgroup_link_release+0x260/0x3a0 kernel/bpf/cgroup.c:796
>> Code: cf ff 5b 5d 41 5c e9 df 2a e9 ff e8 da 2a e9 ff 48 c7 c7 20 f4
>> 9d 89 e8 de a0 3a 06 5b 5d 41 5c e9 c5 2a e9 ff e8 c0 2a e9 ff <0f> 0b
>> e9 57 fe ff ff e8 a4 3d 26 00 e9 2a fe ff ff e8 9a 3d 26 00
>> RSP: 0018:ffffc900019a7dc0 EFLAGS: 00010246
>> RAX: 0000000000040000 RBX: ffff88808c3eac00 RCX: ffffc9000415a000
>> RDX: 0000000000040000 RSI: ffffffff8189bea0 RDI: 0000000000000005
>> RBP: 00000000fffffff4 R08: ffff88809055e000 R09: ffffed1015cc70f4
>> R10: ffffed1015cc70f3 R11: ffff8880ae63879b R12: ffff88808c3eac60
>> R13: ffff88808c3eac10 R14: ffffc90000f32000 R15: ffffffff817f8e60
>> bpf_link_free+0x80/0x140 kernel/bpf/syscall.c:2217
>> bpf_link_put+0x15e/0x1b0 kernel/bpf/syscall.c:2243
>> bpf_link_release+0x33/0x40 kernel/bpf/syscall.c:2251
>> __fput+0x2e9/0x860 fs/file_table.c:280
>> task_work_run+0xf4/0x1b0 kernel/task_work.c:123
>> tracehook_notify_resume include/linux/tracehook.h:188 [inline]
>> exit_to_usermode_loop+0x2fa/0x360 arch/x86/entry/common.c:165
>> prepare_exit_to_usermode arch/x86/entry/common.c:196 [inline]
>> syscall_return_slowpath arch/x86/entry/common.c:279 [inline]
>> do_syscall_64+0x6b1/0x7d0 arch/x86/entry/common.c:305
>> entry_SYSCALL_64_after_hwframe+0x49/0xb3
>> RIP: 0033:0x45c889
>> Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48
>> 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d
>> 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
>> RSP: 002b:00007fddaf43fc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000003
>> RAX: 0000000000000000 RBX: 00007fddaf4406d4 RCX: 000000000045c889
>> RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000005
>> RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000
>> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000006
>> R13: 0000000000000078 R14: 00000000005043d2 R15: 0000000000000000
>> Kernel Offset: disabled
>> Rebooting in 86400 seconds..
>>
>>
>> ---
>> This bug is generated by a bot. It may contain errors.
>> See
>> https://urldefense.proofpoint.com/v2/url?u=https-3A__goo.gl_tpsmEJ&d=DwICaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=vxqvl81C2rT6GOGdPyz8iQ&m=T2Ez0XmyIpHmEa_MPTTUOh61jMDXqwETtTaTbSe-2M4&s=jBcp1pSQqrDLletxcTuqMoEa0bDhfqxI8vS5QM-yBGY&e=
>> for more information about syzbot.
>> syzbot engineers can be reached at syzkaller@googlegroups.com.
>>
>> syzbot will keep track of this bug report. See:
>> https://urldefense.proofpoint.com/v2/url?u=https-3A__goo.gl_tpsmEJ-23status&d=DwICaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=vxqvl81C2rT6GOGdPyz8iQ&m=T2Ez0XmyIpHmEa_MPTTUOh61jMDXqwETtTaTbSe-2M4&s=jgiRP_4-vqlJiCpbXgMh0QfDg8iYJzW-i7MZS8KdapM&e=
>> for how to communicate with syzbot.
>>
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: WARNING in bpf_cgroup_link_release
2020-04-15 16:51 ` Andrii Nakryiko
@ 2020-04-16 10:26 ` Dan Carpenter
2020-04-16 19:47 ` Andrii Nakryiko
0 siblings, 1 reply; 6+ messages in thread
From: Dan Carpenter @ 2020-04-16 10:26 UTC (permalink / raw)
To: Andrii Nakryiko
Cc: Daniel Borkmann, syzbot, ast, bpf, john.fastabend, kafai,
kpsingh, linux-kernel, netdev, songliubraving, syzkaller-bugs,
yhs
On Wed, Apr 15, 2020 at 09:51:40AM -0700, 'Andrii Nakryiko' via syzkaller-bugs wrote:
> On 4/15/20 4:57 AM, Daniel Borkmann wrote:
> > On 4/15/20 8:55 AM, syzbot wrote:
> > > Hello,
> > >
> > > syzbot found the following crash on:
> >
> > Andrii, ptal.
> >
> > > HEAD commit: 1a323ea5 x86: get rid of 'errret' argument to
> > > __get_user_x..
> > > git tree: bpf-next
> > > console output: https://urldefense.proofpoint.com/v2/url?u=https-3A__syzkaller.appspot.com_x_log.txt-3Fx-3D148ccb57e00000&d=DwICaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=vxqvl81C2rT6GOGdPyz8iQ&m=T2Ez0XmyIpHmEa_MPTTUOh61jMDXqwETtTaTbSe-2M4&s=-6XBbsNV1O4X5flrx4Yssfjc56d0qeSHgwHhd92UPJc&e=
> > > kernel config: https://urldefense.proofpoint.com/v2/url?u=https-3A__syzkaller.appspot.com_x_.config-3Fx-3D8c1e98458335a7d1&d=DwICaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=vxqvl81C2rT6GOGdPyz8iQ&m=T2Ez0XmyIpHmEa_MPTTUOh61jMDXqwETtTaTbSe-2M4&s=s5-1AlWtSiBvo66WN4_UXoXMGIGIqsoUCrmAnxNnfX0&e=
> > > dashboard link: https://urldefense.proofpoint.com/v2/url?u=https-3A__syzkaller.appspot.com_bug-3Fextid-3D8a5dadc5c0b1d7055945&d=DwICaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=vxqvl81C2rT6GOGdPyz8iQ&m=T2Ez0XmyIpHmEa_MPTTUOh61jMDXqwETtTaTbSe-2M4&s=hAA0702qJH5EwRwvG0RKmj8FwIRm1O8hvmoS7ne5Dls&e=
> > > compiler: gcc (GCC) 9.0.0 20181231 (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+8a5dadc5c0b1d7055945@syzkaller.appspotmail.com
> > >
> > > ------------[ cut here ]------------
> > > WARNING: CPU: 0 PID: 25081 at kernel/bpf/cgroup.c:796
> > > bpf_cgroup_link_release+0x260/0x3a0 kernel/bpf/cgroup.c:796
>
> This warning is triggered due to __cgroup_bpf_detach returning an error. It
> can do it only in two cases: either attached item is not found, which from
> starting at code some moreI don't see how that can happen. The other reason
> - kmalloc() failing to allocate memory for new effective prog array.
If you look at the log file then this was allocation fault injection in
bpf_prog_array_alloc().
https://syzkaller.appspot.com/x/log.txt?x=148ccb57e00000
regards,
dan carpenter
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: WARNING in bpf_cgroup_link_release
2020-04-16 10:26 ` Dan Carpenter
@ 2020-04-16 19:47 ` Andrii Nakryiko
0 siblings, 0 replies; 6+ messages in thread
From: Andrii Nakryiko @ 2020-04-16 19:47 UTC (permalink / raw)
To: Dan Carpenter
Cc: Andrii Nakryiko, Daniel Borkmann, syzbot, Alexei Starovoitov,
bpf, john fastabend, Martin Lau, KP Singh, open list, Networking,
Song Liu, syzkaller-bugs, Yonghong Song
On Thu, Apr 16, 2020 at 3:29 AM Dan Carpenter <dan.carpenter@oracle.com> wrote:
>
> On Wed, Apr 15, 2020 at 09:51:40AM -0700, 'Andrii Nakryiko' via syzkaller-bugs wrote:
> > On 4/15/20 4:57 AM, Daniel Borkmann wrote:
> > > On 4/15/20 8:55 AM, syzbot wrote:
> > > > Hello,
> > > >
> > > > syzbot found the following crash on:
> > >
> > > Andrii, ptal.
> > >
> > > > HEAD commit: 1a323ea5 x86: get rid of 'errret' argument to
> > > > __get_user_x..
> > > > git tree: bpf-next
> > > > console output: https://urldefense.proofpoint.com/v2/url?u=https-3A__syzkaller.appspot.com_x_log.txt-3Fx-3D148ccb57e00000&d=DwICaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=vxqvl81C2rT6GOGdPyz8iQ&m=T2Ez0XmyIpHmEa_MPTTUOh61jMDXqwETtTaTbSe-2M4&s=-6XBbsNV1O4X5flrx4Yssfjc56d0qeSHgwHhd92UPJc&e=
> > > > kernel config: https://urldefense.proofpoint.com/v2/url?u=https-3A__syzkaller.appspot.com_x_.config-3Fx-3D8c1e98458335a7d1&d=DwICaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=vxqvl81C2rT6GOGdPyz8iQ&m=T2Ez0XmyIpHmEa_MPTTUOh61jMDXqwETtTaTbSe-2M4&s=s5-1AlWtSiBvo66WN4_UXoXMGIGIqsoUCrmAnxNnfX0&e=
> > > > dashboard link: https://urldefense.proofpoint.com/v2/url?u=https-3A__syzkaller.appspot.com_bug-3Fextid-3D8a5dadc5c0b1d7055945&d=DwICaQ&c=5VD0RTtNlTh3ycd41b3MUw&r=vxqvl81C2rT6GOGdPyz8iQ&m=T2Ez0XmyIpHmEa_MPTTUOh61jMDXqwETtTaTbSe-2M4&s=hAA0702qJH5EwRwvG0RKmj8FwIRm1O8hvmoS7ne5Dls&e=
> > > > compiler: gcc (GCC) 9.0.0 20181231 (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+8a5dadc5c0b1d7055945@syzkaller.appspotmail.com
> > > >
> > > > ------------[ cut here ]------------
> > > > WARNING: CPU: 0 PID: 25081 at kernel/bpf/cgroup.c:796
> > > > bpf_cgroup_link_release+0x260/0x3a0 kernel/bpf/cgroup.c:796
> >
> > This warning is triggered due to __cgroup_bpf_detach returning an error. It
> > can do it only in two cases: either attached item is not found, which from
> > starting at code some moreI don't see how that can happen. The other reason
> > - kmalloc() failing to allocate memory for new effective prog array.
>
> If you look at the log file then this was allocation fault injection in
> bpf_prog_array_alloc().
Ah, I see, thanks for pointing this out! So that confirms that it's
not a bug, but just unfortunate result of potentially failing cgroup
BPF program detach code path.
>
> https://syzkaller.appspot.com/x/log.txt?x=148ccb57e00000
>
> regards,
> dan carpenter
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: WARNING in bpf_cgroup_link_release
2020-04-15 6:55 WARNING in bpf_cgroup_link_release syzbot
2020-04-15 11:57 ` Daniel Borkmann
@ 2020-09-01 2:58 ` syzbot
1 sibling, 0 replies; 6+ messages in thread
From: syzbot @ 2020-09-01 2:58 UTC (permalink / raw)
To: andrii.nakryiko, andriin, ast, bpf, dan.carpenter, daniel,
john.fastabend, kafai, kpsingh, linux-kernel, netdev,
songliubraving, syzkaller-bugs, yhs
syzbot has found a reproducer for the following issue on:
HEAD commit: bb8872a1 tipc: fix using smp_processor_id() in preemptible
git tree: net
console output: https://syzkaller.appspot.com/x/log.txt?x=10aa0271900000
kernel config: https://syzkaller.appspot.com/x/.config?x=a0437fdd630bee11
dashboard link: https://syzkaller.appspot.com/bug?extid=8a5dadc5c0b1d7055945
compiler: gcc (GCC) 10.1.0-syz 20200507
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1291cbde900000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12896476900000
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+8a5dadc5c0b1d7055945@syzkaller.appspotmail.com
RBP: ffffffffffffffff R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000009
R13: 00007ffeea853240 R14: 0000000000000000 R15: 0000000000000000
------------[ cut here ]------------
WARNING: CPU: 0 PID: 6859 at kernel/bpf/cgroup.c:833 bpf_cgroup_link_release.part.0+0x28b/0x380 kernel/bpf/cgroup.c:833
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 6859 Comm: syz-executor054 Not tainted 5.9.0-rc1-syzkaller #0
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+0x18f/0x20d lib/dump_stack.c:118
panic+0x2e3/0x75c kernel/panic.c:231
__warn.cold+0x20/0x4a kernel/panic.c:600
report_bug+0x1bd/0x210 lib/bug.c:198
handle_bug+0x38/0x90 arch/x86/kernel/traps.c:234
exc_invalid_op+0x14/0x40 arch/x86/kernel/traps.c:254
asm_exc_invalid_op+0x12/0x20 arch/x86/include/asm/idtentry.h:536
RIP: 0010:bpf_cgroup_link_release.part.0+0x28b/0x380 kernel/bpf/cgroup.c:833
Code: 01 e8 ce e0 cd ff e9 f1 fe ff ff e8 3f 60 e7 ff 48 c7 c7 00 d4 bf 89 e8 83 ad 68 06 5b 5d 41 5c e9 2a 60 e7 ff e8 25 60 e7 ff <0f> 0b e9 01 fe ff ff e8 19 60 e7 ff e8 e4 2a d4 ff 31 ff 89 c3 89
RSP: 0018:ffffc90005367d38 EFLAGS: 00010293
RAX: 0000000000000000 RBX: ffff888094525700 RCX: ffffffff818cdceb
RDX: ffff8880978ec240 RSI: ffffffff818cdeeb RDI: 0000000000000005
RBP: 00000000fffffff4 R08: 0000000000000001 R09: ffffffff89c97453
R10: 0000000000000000 R11: 0000000035383654 R12: ffff888094525768
R13: ffffffffffffffa1 R14: 0000000000000022 R15: 0000000000000008
bpf_cgroup_link_release kernel/bpf/cgroup.c:822 [inline]
bpf_cgroup_link_detach+0x38/0x50 kernel/bpf/cgroup.c:854
link_detach kernel/bpf/syscall.c:4009 [inline]
__do_sys_bpf+0x667/0x4c20 kernel/bpf/syscall.c:4267
do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x442229
Code: e8 1c b4 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 6b 08 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffeea8531e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000442229
RDX: 0000000000000008 RSI: 0000000020000040 RDI: 0000000000000022
RBP: ffffffffffffffff R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000009
R13: 00007ffeea853240 R14: 0000000000000000 R15: 0000000000000000
Kernel Offset: disabled
Rebooting in 86400 seconds..
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2020-09-01 2:58 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-04-15 6:55 WARNING in bpf_cgroup_link_release syzbot
2020-04-15 11:57 ` Daniel Borkmann
2020-04-15 16:51 ` Andrii Nakryiko
2020-04-16 10:26 ` Dan Carpenter
2020-04-16 19:47 ` Andrii Nakryiko
2020-09-01 2:58 ` syzbot
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