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* KMSAN: uninit-value in ebt_stp_mt_check (2)
@ 2018-06-07 17:29 syzbot
  2018-06-07 17:34 ` Dmitry Vyukov
  2018-06-07 21:40 ` syzbot
  0 siblings, 2 replies; 3+ messages in thread
From: syzbot @ 2018-06-07 17:29 UTC (permalink / raw)
  To: bridge, coreteam, davem, fw, kadlec, linux-kernel, netdev,
	netfilter-devel, pablo, stephen, syzkaller-bugs

Hello,

syzbot found the following crash on:

HEAD commit:    c6a6aed994b6 kmsan: remove dead code to trigger syzbot build
git tree:       https://github.com/google/kmsan.git/master
console output: https://syzkaller.appspot.com/x/log.txt?x=17bde74f800000
kernel config:  https://syzkaller.appspot.com/x/.config?x=848e40757852af3e
dashboard link: https://syzkaller.appspot.com/bug?extid=da4494182233c23a5fcf
compiler:       clang version 7.0.0 (trunk 334104)

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+da4494182233c23a5fcf@syzkaller.appspotmail.com

==================================================================
BUG: KMSAN: uninit-value in ebt_stp_mt_check+0x24b/0x450  
net/bridge/netfilter/ebt_stp.c:162
CPU: 0 PID: 12006 Comm: syz-executor7 Not tainted 4.17.0+ #3
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+0x185/0x1d0 lib/dump_stack.c:113
  kmsan_report+0x149/0x260 mm/kmsan/kmsan.c:1084
  __msan_warning_32+0x6e/0xc0 mm/kmsan/kmsan_instr.c:620
  ebt_stp_mt_check+0x24b/0x450 net/bridge/netfilter/ebt_stp.c:162
  xt_check_match+0x1438/0x1650 net/netfilter/x_tables.c:506
  ebt_check_match net/bridge/netfilter/ebtables.c:372 [inline]
  ebt_check_entry net/bridge/netfilter/ebtables.c:702 [inline]
  translate_table+0x4e88/0x6120 net/bridge/netfilter/ebtables.c:943
  do_replace_finish+0x1258/0x2ea0 net/bridge/netfilter/ebtables.c:999
  do_replace+0x719/0x780 net/bridge/netfilter/ebtables.c:1138
  do_ebt_set_ctl+0x2ab/0x3c0 net/bridge/netfilter/ebtables.c:1517
  nf_sockopt net/netfilter/nf_sockopt.c:106 [inline]
  nf_setsockopt+0x47c/0x4e0 net/netfilter/nf_sockopt.c:115
  ip_setsockopt+0x24b/0x2b0 net/ipv4/ip_sockglue.c:1251
  udp_setsockopt+0x108/0x1b0 net/ipv4/udp.c:2416
  sock_common_setsockopt+0x13b/0x170 net/core/sock.c:3039
  __sys_setsockopt+0x496/0x540 net/socket.c:1903
  __do_sys_setsockopt net/socket.c:1914 [inline]
  __se_sys_setsockopt net/socket.c:1911 [inline]
  __x64_sys_setsockopt+0x15c/0x1c0 net/socket.c:1911
  do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:287
  entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x4559f9
RSP: 002b:00007f45b9246c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007f45b92476d4 RCX: 00000000004559f9
RDX: 0000000000000080 RSI: 0000000000000000 RDI: 0000000000000014
RBP: 000000000072bea0 R08: 0000000000000300 R09: 0000000000000000
R10: 0000000020000480 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000004c0d6d R14: 00000000004d07c8 R15: 0000000000000000

Local variable description: ----mtpar.i@translate_table
Variable was created at:
  translate_table+0xbb/0x6120 net/bridge/netfilter/ebtables.c:831
  do_replace_finish+0x1258/0x2ea0 net/bridge/netfilter/ebtables.c:999
==================================================================


---
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: KMSAN: uninit-value in ebt_stp_mt_check (2)
  2018-06-07 17:29 KMSAN: uninit-value in ebt_stp_mt_check (2) syzbot
@ 2018-06-07 17:34 ` Dmitry Vyukov
  2018-06-07 21:40 ` syzbot
  1 sibling, 0 replies; 3+ messages in thread
From: Dmitry Vyukov @ 2018-06-07 17:34 UTC (permalink / raw)
  To: syzbot
  Cc: bridge, coreteam, David Miller, Florian Westphal,
	Jozsef Kadlecsik, LKML, netdev, netfilter-devel,
	Pablo Neira Ayuso, stephen hemminger, syzkaller-bugs

On Thu, Jun 7, 2018 at 7:29 PM, syzbot
<syzbot+da4494182233c23a5fcf@syzkaller.appspotmail.com> wrote:
> Hello,
>
> syzbot found the following crash on:
>
> HEAD commit:    c6a6aed994b6 kmsan: remove dead code to trigger syzbot build
> git tree:       https://github.com/google/kmsan.git/master
> console output: https://syzkaller.appspot.com/x/log.txt?x=17bde74f800000
> kernel config:  https://syzkaller.appspot.com/x/.config?x=848e40757852af3e
> dashboard link: https://syzkaller.appspot.com/bug?extid=da4494182233c23a5fcf
> compiler:       clang version 7.0.0 (trunk 334104)
>
> 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+da4494182233c23a5fcf@syzkaller.appspotmail.com

Hi Stephen,

This strikes again.

The first part of the check is par->nft_compat. I don't see where
ebt_check_entry initializes it. Should it? Or matches should not look at it?



> ==================================================================
> BUG: KMSAN: uninit-value in ebt_stp_mt_check+0x24b/0x450
> net/bridge/netfilter/ebt_stp.c:162
> CPU: 0 PID: 12006 Comm: syz-executor7 Not tainted 4.17.0+ #3
> 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+0x185/0x1d0 lib/dump_stack.c:113
>  kmsan_report+0x149/0x260 mm/kmsan/kmsan.c:1084
>  __msan_warning_32+0x6e/0xc0 mm/kmsan/kmsan_instr.c:620
>  ebt_stp_mt_check+0x24b/0x450 net/bridge/netfilter/ebt_stp.c:162
>  xt_check_match+0x1438/0x1650 net/netfilter/x_tables.c:506
>  ebt_check_match net/bridge/netfilter/ebtables.c:372 [inline]
>  ebt_check_entry net/bridge/netfilter/ebtables.c:702 [inline]
>  translate_table+0x4e88/0x6120 net/bridge/netfilter/ebtables.c:943
>  do_replace_finish+0x1258/0x2ea0 net/bridge/netfilter/ebtables.c:999
>  do_replace+0x719/0x780 net/bridge/netfilter/ebtables.c:1138
>  do_ebt_set_ctl+0x2ab/0x3c0 net/bridge/netfilter/ebtables.c:1517
>  nf_sockopt net/netfilter/nf_sockopt.c:106 [inline]
>  nf_setsockopt+0x47c/0x4e0 net/netfilter/nf_sockopt.c:115
>  ip_setsockopt+0x24b/0x2b0 net/ipv4/ip_sockglue.c:1251
>  udp_setsockopt+0x108/0x1b0 net/ipv4/udp.c:2416
>  sock_common_setsockopt+0x13b/0x170 net/core/sock.c:3039
>  __sys_setsockopt+0x496/0x540 net/socket.c:1903
>  __do_sys_setsockopt net/socket.c:1914 [inline]
>  __se_sys_setsockopt net/socket.c:1911 [inline]
>  __x64_sys_setsockopt+0x15c/0x1c0 net/socket.c:1911
>  do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:287
>  entry_SYSCALL_64_after_hwframe+0x44/0xa9
> RIP: 0033:0x4559f9
> RSP: 002b:00007f45b9246c68 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
> RAX: ffffffffffffffda RBX: 00007f45b92476d4 RCX: 00000000004559f9
> RDX: 0000000000000080 RSI: 0000000000000000 RDI: 0000000000000014
> RBP: 000000000072bea0 R08: 0000000000000300 R09: 0000000000000000
> R10: 0000000020000480 R11: 0000000000000246 R12: 00000000ffffffff
> R13: 00000000004c0d6d R14: 00000000004d07c8 R15: 0000000000000000
>
> Local variable description: ----mtpar.i@translate_table
> Variable was created at:
>  translate_table+0xbb/0x6120 net/bridge/netfilter/ebtables.c:831
>  do_replace_finish+0x1258/0x2ea0 net/bridge/netfilter/ebtables.c:999
> ==================================================================
>
>
> ---
> 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.
>
> --
> 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/0000000000009a3b5b056e109e42%40google.com.
> For more options, visit https://groups.google.com/d/optout.

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: KMSAN: uninit-value in ebt_stp_mt_check (2)
  2018-06-07 17:29 KMSAN: uninit-value in ebt_stp_mt_check (2) syzbot
  2018-06-07 17:34 ` Dmitry Vyukov
@ 2018-06-07 21:40 ` syzbot
  1 sibling, 0 replies; 3+ messages in thread
From: syzbot @ 2018-06-07 21:40 UTC (permalink / raw)
  To: bridge, coreteam, davem, dvyukov, fw, kadlec, linux-kernel,
	netdev, netfilter-devel, pablo, stephen, syzkaller-bugs

syzbot has found a reproducer for the following crash on:

HEAD commit:    c6a6aed994b6 kmsan: remove dead code to trigger syzbot build
git tree:       https://github.com/google/kmsan.git/master
console output: https://syzkaller.appspot.com/x/log.txt?x=122606bf800000
kernel config:  https://syzkaller.appspot.com/x/.config?x=848e40757852af3e
dashboard link: https://syzkaller.appspot.com/bug?extid=da4494182233c23a5fcf
compiler:       clang version 7.0.0 (trunk 334104)
syzkaller repro:https://syzkaller.appspot.com/x/repro.syz?x=121f481f800000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=121fbbd7800000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+da4494182233c23a5fcf@syzkaller.appspotmail.com

random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
random: sshd: uninitialized urandom read (32 bytes read)
==================================================================
BUG: KMSAN: uninit-value in ebt_stp_mt_check+0x24b/0x450  
net/bridge/netfilter/ebt_stp.c:162
CPU: 1 PID: 4523 Comm: syz-executor710 Not tainted 4.17.0+ #3
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+0x185/0x1d0 lib/dump_stack.c:113
  kmsan_report+0x149/0x260 mm/kmsan/kmsan.c:1084
  __msan_warning_32+0x6e/0xc0 mm/kmsan/kmsan_instr.c:620
  ebt_stp_mt_check+0x24b/0x450 net/bridge/netfilter/ebt_stp.c:162
  xt_check_match+0x1438/0x1650 net/netfilter/x_tables.c:506
  ebt_check_match net/bridge/netfilter/ebtables.c:372 [inline]
  ebt_check_entry net/bridge/netfilter/ebtables.c:702 [inline]
  translate_table+0x4e88/0x6120 net/bridge/netfilter/ebtables.c:943
  do_replace_finish+0x1258/0x2ea0 net/bridge/netfilter/ebtables.c:999
  do_replace+0x719/0x780 net/bridge/netfilter/ebtables.c:1138
  do_ebt_set_ctl+0x2ab/0x3c0 net/bridge/netfilter/ebtables.c:1517
  nf_sockopt net/netfilter/nf_sockopt.c:106 [inline]
  nf_setsockopt+0x47c/0x4e0 net/netfilter/nf_sockopt.c:115
  ip_setsockopt+0x24b/0x2b0 net/ipv4/ip_sockglue.c:1251
  udp_setsockopt+0x108/0x1b0 net/ipv4/udp.c:2416
  sock_common_setsockopt+0x13b/0x170 net/core/sock.c:3039
  __sys_setsockopt+0x496/0x540 net/socket.c:1903
  __do_sys_setsockopt net/socket.c:1914 [inline]
  __se_sys_setsockopt net/socket.c:1911 [inline]
  __x64_sys_setsockopt+0x15c/0x1c0 net/socket.c:1911
  do_syscall_64+0x15b/0x230 arch/x86/entry/common.c:287
  entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x43fd89
RSP: 002b:00007ffc9d7edb28 EFLAGS: 00000213 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fd89
RDX: 0000000000000080 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00000000006ca018 R08: 0000000000000300 R09: 00000000004002c8
R10: 0000000020000480 R11: 0000000000000213 R12: 00000000004016b0
R13: 0000000000401740 R14: 0000000000000000 R15: 0000000000000000

Local variable description: ----mtpar.i@translate_table
Variable was created at:
  translate_table+0xbb/0x6120 net/bridge/netfilter/ebtables.c:831
  do_replace_finish+0x1258/0x2ea0 net/bridge/netfilter/ebtables.c:999
==================================================================

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2018-06-07 21:40 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
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2018-06-07 17:29 KMSAN: uninit-value in ebt_stp_mt_check (2) syzbot
2018-06-07 17:34 ` Dmitry Vyukov
2018-06-07 21:40 ` syzbot

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