Hello,
syzkaller hit the following crash on
b2cd1df66037e7c4697c7e40496bf7e4a5e16a2d
git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master
compiler: gcc (GCC) 7.1.1 20170620
.config is attached
Raw console output is attached.
C reproducer is attached
syzkaller reproducer is attached. See https://goo.gl/kgGztJ
for information about syzkaller reproducers
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: [email protected]
It will help syzbot understand when the bug is fixed. See footer for
details.
If you forward the report, please keep this part and the footer.
==================================================================
BUG: KASAN: use-after-free in tipc_group_size+0x40/0x50 net/tipc/group.c:158
Read of size 2 at addr ffff8801c08ba280 by task syzkaller447710/3513
CPU: 0 PID: 3513 Comm: syzkaller447710 Not tainted 4.15.0-rc7+ #252
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:17 [inline]
dump_stack+0x194/0x257 lib/dump_stack.c:53
print_address_description+0x73/0x250 mm/kasan/report.c:252
kasan_report_error mm/kasan/report.c:351 [inline]
kasan_report+0x25b/0x340 mm/kasan/report.c:409
__asan_report_load2_noabort+0x14/0x20 mm/kasan/report.c:428
tipc_group_size+0x40/0x50 net/tipc/group.c:158
tipc_poll+0x374/0x4f0 net/tipc/socket.c:739
sock_poll+0x141/0x320 net/socket.c:1117
do_pollfd fs/select.c:822 [inline]
do_poll fs/select.c:872 [inline]
do_sys_poll+0x715/0x10b0 fs/select.c:966
SYSC_poll fs/select.c:1024 [inline]
SyS_poll+0x10d/0x450 fs/select.c:1012
entry_SYSCALL_64_fastpath+0x23/0x9a
RIP: 0033:0x445cb9
RSP: 002b:00007f04886b1ce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000007
RAX: ffffffffffffffda RBX: 00000000006dac3c RCX: 0000000000445cb9
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000020fa2ff8
RBP: 00000000006dac38 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffc84d56d7f R14: 00007f04886b29c0 R15: 0000000000000005
Allocated by task 3510:
save_stack+0x43/0xd0 mm/kasan/kasan.c:447
set_track mm/kasan/kasan.c:459 [inline]
kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551
kmem_cache_alloc_trace+0x136/0x750 mm/slab.c:3610
kmalloc include/linux/slab.h:499 [inline]
kzalloc include/linux/slab.h:688 [inline]
tipc_group_create+0x116/0x9c0 net/tipc/group.c:167
tipc_sk_join net/tipc/socket.c:2747 [inline]
tipc_setsockopt+0x249/0xc10 net/tipc/socket.c:2861
SYSC_setsockopt net/socket.c:1829 [inline]
SyS_setsockopt+0x189/0x360 net/socket.c:1808
entry_SYSCALL_64_fastpath+0x23/0x9a
Freed by task 3510:
save_stack+0x43/0xd0 mm/kasan/kasan.c:447
set_track mm/kasan/kasan.c:459 [inline]
kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524
__cache_free mm/slab.c:3488 [inline]
kfree+0xd6/0x260 mm/slab.c:3803
tipc_group_delete+0x2c8/0x3d0 net/tipc/group.c:206
tipc_sk_join net/tipc/socket.c:2760 [inline]
tipc_setsockopt+0xb0d/0xc10 net/tipc/socket.c:2861
SYSC_setsockopt net/socket.c:1829 [inline]
SyS_setsockopt+0x189/0x360 net/socket.c:1808
entry_SYSCALL_64_fastpath+0x23/0x9a
The buggy address belongs to the object at ffff8801c08ba200
which belongs to the cache kmalloc-192 of size 192
The buggy address is located 128 bytes inside of
192-byte region [ffff8801c08ba200, ffff8801c08ba2c0)
The buggy address belongs to the page:
page:ffffea0007022e80 count:1 mapcount:0 mapping:ffff8801c08ba000 index:0x0
flags: 0x2fffc0000000100(slab)
raw: 02fffc0000000100 ffff8801c08ba000 0000000000000000 0000000100000010
raw: ffffea00071338a0 ffffea0006fe2360 ffff8801dac00040 0000000000000000
page dumped because: kasan: bad access detected
Memory state around the buggy address:
ffff8801c08ba180: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
ffff8801c08ba200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ffff8801c08ba280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
^
ffff8801c08ba300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8801c08ba380: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
==================================================================
---
This bug is generated by a dumb bot. It may contain errors.
See https://goo.gl/tpsmEJ for details.
Direct all questions to [email protected].
syzbot will keep track of this bug report.
If you forgot to add the Reported-by tag, once the fix for this bug is
merged
into any tree, please reply to this email with:
#syz fix: exact-commit-title
If you want to test a patch for this bug, please reply with:
#syz test: git://repo/address.git branch
and provide the patch inline or as an attachment.
To mark this as a duplicate of another syzbot report, please reply with:
#syz dup: exact-subject-of-another-report
If it's a one-off invalid bug report, please reply with:
#syz invalid
Note: if the crash happens again, it will cause creation of a new bug
report.
Note: all commands must start from beginning of the line in the email body.
On Mon, Jan 8, 2018 at 6:58 AM, syzbot
<[email protected]> wrote:
> Hello,
>
> syzkaller hit the following crash on
> b2cd1df66037e7c4697c7e40496bf7e4a5e16a2d
> git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/master
> compiler: gcc (GCC) 7.1.1 20170620
> .config is attached
> Raw console output is attached.
> C reproducer is attached
> syzkaller reproducer is attached. See https://goo.gl/kgGztJ
> for information about syzkaller reproducers
>
>
> IMPORTANT: if you fix the bug, please add the following tag to the commit:
> Reported-by: [email protected]
> It will help syzbot understand when the bug is fixed. See footer for
> details.
> If you forward the report, please keep this part and the footer.
>
> ==================================================================
> BUG: KASAN: use-after-free in tipc_group_size+0x40/0x50 net/tipc/group.c:158
> Read of size 2 at addr ffff8801c08ba280 by task syzkaller447710/3513
>
> CPU: 0 PID: 3513 Comm: syzkaller447710 Not tainted 4.15.0-rc7+ #252
> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
> Google 01/01/2011
> Call Trace:
> __dump_stack lib/dump_stack.c:17 [inline]
> dump_stack+0x194/0x257 lib/dump_stack.c:53
> print_address_description+0x73/0x250 mm/kasan/report.c:252
> kasan_report_error mm/kasan/report.c:351 [inline]
> kasan_report+0x25b/0x340 mm/kasan/report.c:409
> __asan_report_load2_noabort+0x14/0x20 mm/kasan/report.c:428
> tipc_group_size+0x40/0x50 net/tipc/group.c:158
> tipc_poll+0x374/0x4f0 net/tipc/socket.c:739
Seems we have to lock the sock for tipc_group_size() in
tipc_poll().
> sock_poll+0x141/0x320 net/socket.c:1117
> do_pollfd fs/select.c:822 [inline]
> do_poll fs/select.c:872 [inline]
> do_sys_poll+0x715/0x10b0 fs/select.c:966
> SYSC_poll fs/select.c:1024 [inline]
> SyS_poll+0x10d/0x450 fs/select.c:1012
> entry_SYSCALL_64_fastpath+0x23/0x9a
> RIP: 0033:0x445cb9
> RSP: 002b:00007f04886b1ce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000007
> RAX: ffffffffffffffda RBX: 00000000006dac3c RCX: 0000000000445cb9
> RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000020fa2ff8
> RBP: 00000000006dac38 R08: 0000000000000000 R09: 0000000000000000
> R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
> R13: 00007ffc84d56d7f R14: 00007f04886b29c0 R15: 0000000000000005
>
> Allocated by task 3510:
> save_stack+0x43/0xd0 mm/kasan/kasan.c:447
> set_track mm/kasan/kasan.c:459 [inline]
> kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551
> kmem_cache_alloc_trace+0x136/0x750 mm/slab.c:3610
> kmalloc include/linux/slab.h:499 [inline]
> kzalloc include/linux/slab.h:688 [inline]
> tipc_group_create+0x116/0x9c0 net/tipc/group.c:167
> tipc_sk_join net/tipc/socket.c:2747 [inline]
> tipc_setsockopt+0x249/0xc10 net/tipc/socket.c:2861
> SYSC_setsockopt net/socket.c:1829 [inline]
> SyS_setsockopt+0x189/0x360 net/socket.c:1808
> entry_SYSCALL_64_fastpath+0x23/0x9a
>
> Freed by task 3510:
> save_stack+0x43/0xd0 mm/kasan/kasan.c:447
> set_track mm/kasan/kasan.c:459 [inline]
> kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524
> __cache_free mm/slab.c:3488 [inline]
> kfree+0xd6/0x260 mm/slab.c:3803
> tipc_group_delete+0x2c8/0x3d0 net/tipc/group.c:206
> tipc_sk_join net/tipc/socket.c:2760 [inline]
> tipc_setsockopt+0xb0d/0xc10 net/tipc/socket.c:2861
> SYSC_setsockopt net/socket.c:1829 [inline]
> SyS_setsockopt+0x189/0x360 net/socket.c:1808
> entry_SYSCALL_64_fastpath+0x23/0x9a
>
> The buggy address belongs to the object at ffff8801c08ba200
> which belongs to the cache kmalloc-192 of size 192
> The buggy address is located 128 bytes inside of
> 192-byte region [ffff8801c08ba200, ffff8801c08ba2c0)
> The buggy address belongs to the page:
> page:ffffea0007022e80 count:1 mapcount:0 mapping:ffff8801c08ba000 index:0x0
> flags: 0x2fffc0000000100(slab)
> raw: 02fffc0000000100 ffff8801c08ba000 0000000000000000 0000000100000010
> raw: ffffea00071338a0 ffffea0006fe2360 ffff8801dac00040 0000000000000000
> page dumped because: kasan: bad access detected
>
> Memory state around the buggy address:
> ffff8801c08ba180: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
> ffff8801c08ba200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>>
>> ffff8801c08ba280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>
> ^
> ffff8801c08ba300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> ffff8801c08ba380: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
> ==================================================================
>
>
> ---
> This bug is generated by a dumb bot. It may contain errors.
> See https://goo.gl/tpsmEJ for details.
> Direct all questions to [email protected].
>
> syzbot will keep track of this bug report.
> If you forgot to add the Reported-by tag, once the fix for this bug is
> merged
> into any tree, please reply to this email with:
> #syz fix: exact-commit-title
> If you want to test a patch for this bug, please reply with:
> #syz test: git://repo/address.git branch
> and provide the patch inline or as an attachment.
> To mark this as a duplicate of another syzbot report, please reply with:
> #syz dup: exact-subject-of-another-report
> If it's a one-off invalid bug report, please reply with:
> #syz invalid
> Note: if the crash happens again, it will cause creation of a new bug
> report.
> Note: all commands must start from beginning of the line in the email body.
> -----Original Message-----
> From: Cong Wang [mailto:[email protected]]
> Sent: Monday, January 08, 2018 13:44
> To: syzbot <[email protected]>
> Cc: David Miller <[email protected]>; Jon Maloy
> <[email protected]>; LKML <[email protected]>; Linux
> Kernel Network Developers <[email protected]>; syzkaller-
> [email protected]; [email protected]; Ying Xue
> <[email protected]>
> Subject: Re: KASAN: use-after-free Read in tipc_group_size
>
> On Mon, Jan 8, 2018 at 6:58 AM, syzbot
> <[email protected]> wrote:
> > Hello,
> >
> > syzkaller hit the following crash on
> > b2cd1df66037e7c4697c7e40496bf7e4a5e16a2d
> > git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/maste
> > r
> > compiler: gcc (GCC) 7.1.1 20170620
> > .config is attached
> > Raw console output is attached.
> > C reproducer is attached
> > syzkaller reproducer is attached. See https://goo.gl/kgGztJ for
> > information about syzkaller reproducers
> >
> >
> > IMPORTANT: if you fix the bug, please add the following tag to the commit:
> > Reported-by: [email protected]
> > It will help syzbot understand when the bug is fixed. See footer for
> > details.
> > If you forward the report, please keep this part and the footer.
> >
> >
> ==========================================================
> ========
> > BUG: KASAN: use-after-free in tipc_group_size+0x40/0x50
> > net/tipc/group.c:158 Read of size 2 at addr ffff8801c08ba280 by task
> > syzkaller447710/3513
> >
> > CPU: 0 PID: 3513 Comm: syzkaller447710 Not tainted 4.15.0-rc7+ #252
> > Hardware name: Google Google Compute Engine/Google Compute Engine,
> > BIOS Google 01/01/2011 Call Trace:
> > __dump_stack lib/dump_stack.c:17 [inline]
> > dump_stack+0x194/0x257 lib/dump_stack.c:53
> > print_address_description+0x73/0x250 mm/kasan/report.c:252
> > kasan_report_error mm/kasan/report.c:351 [inline]
> > kasan_report+0x25b/0x340 mm/kasan/report.c:409
> > __asan_report_load2_noabort+0x14/0x20 mm/kasan/report.c:428
> > tipc_group_size+0x40/0x50 net/tipc/group.c:158
> > tipc_poll+0x374/0x4f0 net/tipc/socket.c:739
>
> Seems we have to lock the sock for tipc_group_size() in tipc_poll().
Not quite. I think it is that we initialize 'grp' on the stack before we call sock_poll_wait() and access it after it returns.
This is anyway fixed in patch #9 of the series I just sent to net-next, where the poll() handling for group members is redesigned.
///jon
>
>
> > sock_poll+0x141/0x320 net/socket.c:1117 do_pollfd fs/select.c:822
> > [inline] do_poll fs/select.c:872 [inline]
> > do_sys_poll+0x715/0x10b0 fs/select.c:966 SYSC_poll fs/select.c:1024
> > [inline]
> > SyS_poll+0x10d/0x450 fs/select.c:1012
> > entry_SYSCALL_64_fastpath+0x23/0x9a
> > RIP: 0033:0x445cb9
> > RSP: 002b:00007f04886b1ce8 EFLAGS: 00000246 ORIG_RAX:
> 0000000000000007
> > RAX: ffffffffffffffda RBX: 00000000006dac3c RCX: 0000000000445cb9
> > RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000020fa2ff8
> > RBP: 00000000006dac38 R08: 0000000000000000 R09: 0000000000000000
> > R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
> > R13: 00007ffc84d56d7f R14: 00007f04886b29c0 R15: 0000000000000005
> >
> > Allocated by task 3510:
> > save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track
> > mm/kasan/kasan.c:459 [inline]
> > kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:551
> > kmem_cache_alloc_trace+0x136/0x750 mm/slab.c:3610 kmalloc
> > include/linux/slab.h:499 [inline] kzalloc include/linux/slab.h:688
> > [inline]
> > tipc_group_create+0x116/0x9c0 net/tipc/group.c:167 tipc_sk_join
> > net/tipc/socket.c:2747 [inline]
> > tipc_setsockopt+0x249/0xc10 net/tipc/socket.c:2861 SYSC_setsockopt
> > net/socket.c:1829 [inline]
> > SyS_setsockopt+0x189/0x360 net/socket.c:1808
> > entry_SYSCALL_64_fastpath+0x23/0x9a
> >
> > Freed by task 3510:
> > save_stack+0x43/0xd0 mm/kasan/kasan.c:447 set_track
> > mm/kasan/kasan.c:459 [inline]
> > kasan_slab_free+0x71/0xc0 mm/kasan/kasan.c:524 __cache_free
> > mm/slab.c:3488 [inline]
> > kfree+0xd6/0x260 mm/slab.c:3803
> > tipc_group_delete+0x2c8/0x3d0 net/tipc/group.c:206 tipc_sk_join
> > net/tipc/socket.c:2760 [inline]
> > tipc_setsockopt+0xb0d/0xc10 net/tipc/socket.c:2861 SYSC_setsockopt
> > net/socket.c:1829 [inline]
> > SyS_setsockopt+0x189/0x360 net/socket.c:1808
> > entry_SYSCALL_64_fastpath+0x23/0x9a
> >
> > The buggy address belongs to the object at ffff8801c08ba200 which
> > belongs to the cache kmalloc-192 of size 192 The buggy address is
> > located 128 bytes inside of 192-byte region [ffff8801c08ba200,
> > ffff8801c08ba2c0) The buggy address belongs to the page:
> > page:ffffea0007022e80 count:1 mapcount:0 mapping:ffff8801c08ba000
> > index:0x0
> > flags: 0x2fffc0000000100(slab)
> > raw: 02fffc0000000100 ffff8801c08ba000 0000000000000000
> > 0000000100000010
> > raw: ffffea00071338a0 ffffea0006fe2360 ffff8801dac00040
> > 0000000000000000 page dumped because: kasan: bad access detected
> >
> > Memory state around the buggy address:
> > ffff8801c08ba180: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
> > ffff8801c08ba200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> >>
> >> ffff8801c08ba280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
> >
> > ^
> > ffff8801c08ba300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
> > ffff8801c08ba380: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
> >
> ==========================================================
> ========
> >
> >
> > ---
> > This bug is generated by a dumb bot. It may contain errors.
> > See https://goo.gl/tpsmEJ for details.
> > Direct all questions to [email protected].
> >
> > syzbot will keep track of this bug report.
> > If you forgot to add the Reported-by tag, once the fix for this bug is
> > merged into any tree, please reply to this email with:
> > #syz fix: exact-commit-title
> > If you want to test a patch for this bug, please reply with:
> > #syz test: git://repo/address.git branch and provide the patch inline
> > or as an attachment.
> > To mark this as a duplicate of another syzbot report, please reply with:
> > #syz dup: exact-subject-of-another-report If it's a one-off invalid
> > bug report, please reply with:
> > #syz invalid
> > Note: if the crash happens again, it will cause creation of a new bug
> > report.
> > Note: all commands must start from beginning of the line in the email body.
On Mon, Jan 08, 2018 at 08:11:35PM +0000, Jon Maloy wrote:
>
>
> > -----Original Message-----
> > From: Cong Wang [mailto:[email protected]]
> > Sent: Monday, January 08, 2018 13:44
> > To: syzbot <[email protected]>
> > Cc: David Miller <[email protected]>; Jon Maloy
> > <[email protected]>; LKML <[email protected]>; Linux
> > Kernel Network Developers <[email protected]>; syzkaller-
> > [email protected]; [email protected]; Ying Xue
> > <[email protected]>
> > Subject: Re: KASAN: use-after-free Read in tipc_group_size
> >
> > On Mon, Jan 8, 2018 at 6:58 AM, syzbot
> > <[email protected]> wrote:
> > > Hello,
> > >
> > > syzkaller hit the following crash on
> > > b2cd1df66037e7c4697c7e40496bf7e4a5e16a2d
> > > git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/maste
> > > r
> > > compiler: gcc (GCC) 7.1.1 20170620
> > > .config is attached
> > > Raw console output is attached.
> > > C reproducer is attached
> > > syzkaller reproducer is attached. See https://goo.gl/kgGztJ for
> > > information about syzkaller reproducers
> > >
> > >
> > > IMPORTANT: if you fix the bug, please add the following tag to the commit:
> > > Reported-by: [email protected]
> > > It will help syzbot understand when the bug is fixed. See footer for
> > > details.
> > > If you forward the report, please keep this part and the footer.
> > >
> > >
> > ==========================================================
> > ========
> > > BUG: KASAN: use-after-free in tipc_group_size+0x40/0x50
> > > net/tipc/group.c:158 Read of size 2 at addr ffff8801c08ba280 by task
> > > syzkaller447710/3513
> > >
> > > CPU: 0 PID: 3513 Comm: syzkaller447710 Not tainted 4.15.0-rc7+ #252
> > > Hardware name: Google Google Compute Engine/Google Compute Engine,
> > > BIOS Google 01/01/2011 Call Trace:
> > > __dump_stack lib/dump_stack.c:17 [inline]
> > > dump_stack+0x194/0x257 lib/dump_stack.c:53
> > > print_address_description+0x73/0x250 mm/kasan/report.c:252
> > > kasan_report_error mm/kasan/report.c:351 [inline]
> > > kasan_report+0x25b/0x340 mm/kasan/report.c:409
> > > __asan_report_load2_noabort+0x14/0x20 mm/kasan/report.c:428
> > > tipc_group_size+0x40/0x50 net/tipc/group.c:158
> > > tipc_poll+0x374/0x4f0 net/tipc/socket.c:739
> >
> > Seems we have to lock the sock for tipc_group_size() in tipc_poll().
>
> Not quite. I think it is that we initialize 'grp' on the stack before we call sock_poll_wait() and access it after it returns.
> This is anyway fixed in patch #9 of the series I just sent to net-next, where the poll() handling for group members is redesigned.
>
> ///jon
>
Last occurred on Jan 16. Seems to have been fixed by commit 60c2530696320:
#syz fix: tipc: fix race between poll() and setsockopt()
- Eric