* BUG: corrupted list in nf_tables_commit
@ 2020-01-16 0:25 syzbot
2020-01-16 11:03 ` [PATCH nf] netfilter: nf_tables: fix flowtable list del corruption Florian Westphal
2020-01-17 4:45 ` BUG: corrupted list in nf_tables_commit syzbot
0 siblings, 2 replies; 4+ messages in thread
From: syzbot @ 2020-01-16 0:25 UTC (permalink / raw)
To: coreteam, davem, fw, kadlec, linux-kernel, netdev,
netfilter-devel, pablo, syzkaller-bugs
Hello,
syzbot found the following crash on:
HEAD commit: 51d69817 Merge tag 'platform-drivers-x86-v5.5-3' of git://..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16218315e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=d9290aeb7e6cf1c4
dashboard link: https://syzkaller.appspot.com/bug?extid=37a6804945a3a13b1572
compiler: gcc (GCC) 9.0.0 20181231 (experimental)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16ad1821e00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17d8fc35e00000
IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+37a6804945a3a13b1572@syzkaller.appspotmail.com
list_del corruption, ffff88808c9bb000->prev is LIST_POISON2
(dead000000000122)
------------[ cut here ]------------
kernel BUG at lib/list_debug.c:48!
invalid opcode: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 9707 Comm: syz-executor974 Not tainted 5.5.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS
Google 01/01/2011
RIP: 0010:__list_del_entry_valid.cold+0x37/0x4f lib/list_debug.c:48
Code: be fd 0f 0b 4c 89 ea 4c 89 f6 48 c7 c7 20 66 71 88 e8 c0 e7 be fd 0f
0b 4c 89 e2 4c 89 f6 48 c7 c7 80 66 71 88 e8 ac e7 be fd <0f> 0b 4c 89 f6
48 c7 c7 40 67 71 88 e8 9b e7 be fd 0f 0b cc cc cc
RSP: 0018:ffffc900020273f0 EFLAGS: 00010282
RAX: 000000000000004e RBX: ffff88808c9bb000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff815e5396 RDI: fffff52000404e70
RBP: ffffc90002027408 R08: 000000000000004e R09: ffffed1015d06621
R10: ffffed1015d06620 R11: ffff8880ae833107 R12: dead000000000122
R13: ffff888093e70d80 R14: ffff88808c9bb000 R15: dffffc0000000000
FS: 0000000000d18880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020003ac0 CR3: 0000000096a25000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
__list_del_entry include/linux/list.h:131 [inline]
list_del_rcu include/linux/rculist.h:148 [inline]
nf_tables_commit+0x1068/0x3b30 net/netfilter/nf_tables_api.c:7183
nfnetlink_rcv_batch+0xc78/0x17a0 net/netfilter/nfnetlink.c:485
nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:543 [inline]
nfnetlink_rcv+0x3e7/0x460 net/netfilter/nfnetlink.c:561
netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline]
netlink_unicast+0x58c/0x7d0 net/netlink/af_netlink.c:1328
netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1917
sock_sendmsg_nosec net/socket.c:639 [inline]
sock_sendmsg+0xd7/0x130 net/socket.c:659
____sys_sendmsg+0x753/0x880 net/socket.c:2330
___sys_sendmsg+0x100/0x170 net/socket.c:2384
__sys_sendmsg+0x105/0x1d0 net/socket.c:2417
__do_sys_sendmsg net/socket.c:2426 [inline]
__se_sys_sendmsg net/socket.c:2424 [inline]
__x64_sys_sendmsg+0x78/0xb0 net/socket.c:2424
do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x441aa9
Code: e8 fc ab 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 9b 09 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffcfa467588 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 0000000000441aa9
RDX: 0000000000000042 RSI: 0000000020003ac0 RDI: 0000000000000003
RBP: 0000000000006f6c R08: 00000000004002c8 R09: 00000000004002c8
R10: 0000000000000004 R11: 0000000000000246 R12: 00000000004028d0
R13: 0000000000402960 R14: 0000000000000000 R15: 0000000000000000
Modules linked in:
---[ end trace 9581ba900963d50f ]---
RIP: 0010:__list_del_entry_valid.cold+0x37/0x4f lib/list_debug.c:48
Code: be fd 0f 0b 4c 89 ea 4c 89 f6 48 c7 c7 20 66 71 88 e8 c0 e7 be fd 0f
0b 4c 89 e2 4c 89 f6 48 c7 c7 80 66 71 88 e8 ac e7 be fd <0f> 0b 4c 89 f6
48 c7 c7 40 67 71 88 e8 9b e7 be fd 0f 0b cc cc cc
RSP: 0018:ffffc900020273f0 EFLAGS: 00010282
RAX: 000000000000004e RBX: ffff88808c9bb000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff815e5396 RDI: fffff52000404e70
RBP: ffffc90002027408 R08: 000000000000004e R09: ffffed1015d06621
R10: ffffed1015d06620 R11: ffff8880ae833107 R12: dead000000000122
R13: ffff888093e70d80 R14: ffff88808c9bb000 R15: dffffc0000000000
FS: 0000000000d18880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020003ac0 CR3: 0000000096a25000 CR4: 00000000001406f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
---
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.
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
* [PATCH nf] netfilter: nf_tables: fix flowtable list del corruption
2020-01-16 0:25 BUG: corrupted list in nf_tables_commit syzbot
@ 2020-01-16 11:03 ` Florian Westphal
2020-01-16 13:54 ` Pablo Neira Ayuso
2020-01-17 4:45 ` BUG: corrupted list in nf_tables_commit syzbot
1 sibling, 1 reply; 4+ messages in thread
From: Florian Westphal @ 2020-01-16 11:03 UTC (permalink / raw)
To: netfilter-devel
Cc: syzkaller-bugs, netdev, Florian Westphal, syzbot+37a6804945a3a13b1572
syzbot reported following crash:
list_del corruption, ffff88808c9bb000->prev is LIST_POISON2 (dead000000000122)
[..]
Call Trace:
__list_del_entry include/linux/list.h:131 [inline]
list_del_rcu include/linux/rculist.h:148 [inline]
nf_tables_commit+0x1068/0x3b30 net/netfilter/nf_tables_api.c:7183
[..]
The commit transaction list has:
NFT_MSG_NEWTABLE
NFT_MSG_NEWFLOWTABLE
NFT_MSG_DELFLOWTABLE
NFT_MSG_DELTABLE
A missing generation check during DELTABLE processing causes it to queue
the DELFLOWTABLE operation a second time, so we corrupt the list here:
case NFT_MSG_DELFLOWTABLE:
list_del_rcu(&nft_trans_flowtable(trans)->list);
nf_tables_flowtable_notify(&trans->ctx,
because we have two different DELFLOWTABLE transactions for the same
flowtable. We then call list_del_rcu() twice for the same flowtable->list.
The object handling seems to suffer from the same bug so add a generation
check too and only queue delete transactions for flowtables/objects that
are still active in the next generation.
Reported-by: syzbot+37a6804945a3a13b1572@syzkaller.appspotmail.com
Fixes: 3b49e2e94e6eb ("netfilter: nf_tables: add flow table netlink frontend")
Signed-off-by: Florian Westphal <fw@strlen.de>
---
net/netfilter/nf_tables_api.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 5a1a6632e3a6..9ba1747686ed 100644
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -1047,12 +1047,18 @@ static int nft_flush_table(struct nft_ctx *ctx)
}
list_for_each_entry_safe(flowtable, nft, &ctx->table->flowtables, list) {
+ if (!nft_is_active_next(ctx->net, flowtable))
+ continue;
+
err = nft_delflowtable(ctx, flowtable);
if (err < 0)
goto out;
}
list_for_each_entry_safe(obj, ne, &ctx->table->objects, list) {
+ if (!nft_is_active_next(ctx->net, obj))
+ continue;
+
err = nft_delobj(ctx, obj);
if (err < 0)
goto out;
--
2.24.1
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH nf] netfilter: nf_tables: fix flowtable list del corruption
2020-01-16 11:03 ` [PATCH nf] netfilter: nf_tables: fix flowtable list del corruption Florian Westphal
@ 2020-01-16 13:54 ` Pablo Neira Ayuso
0 siblings, 0 replies; 4+ messages in thread
From: Pablo Neira Ayuso @ 2020-01-16 13:54 UTC (permalink / raw)
To: Florian Westphal
Cc: netfilter-devel, syzkaller-bugs, netdev, syzbot+37a6804945a3a13b1572
On Thu, Jan 16, 2020 at 12:03:01PM +0100, Florian Westphal wrote:
> syzbot reported following crash:
>
> list_del corruption, ffff88808c9bb000->prev is LIST_POISON2 (dead000000000122)
> [..]
> Call Trace:
> __list_del_entry include/linux/list.h:131 [inline]
> list_del_rcu include/linux/rculist.h:148 [inline]
> nf_tables_commit+0x1068/0x3b30 net/netfilter/nf_tables_api.c:7183
> [..]
>
> The commit transaction list has:
>
> NFT_MSG_NEWTABLE
> NFT_MSG_NEWFLOWTABLE
> NFT_MSG_DELFLOWTABLE
> NFT_MSG_DELTABLE
>
> A missing generation check during DELTABLE processing causes it to queue
> the DELFLOWTABLE operation a second time, so we corrupt the list here:
>
> case NFT_MSG_DELFLOWTABLE:
> list_del_rcu(&nft_trans_flowtable(trans)->list);
> nf_tables_flowtable_notify(&trans->ctx,
>
> because we have two different DELFLOWTABLE transactions for the same
> flowtable. We then call list_del_rcu() twice for the same flowtable->list.
>
> The object handling seems to suffer from the same bug so add a generation
> check too and only queue delete transactions for flowtables/objects that
> are still active in the next generation.
Applied, thanks.
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: BUG: corrupted list in nf_tables_commit
2020-01-16 0:25 BUG: corrupted list in nf_tables_commit syzbot
2020-01-16 11:03 ` [PATCH nf] netfilter: nf_tables: fix flowtable list del corruption Florian Westphal
@ 2020-01-17 4:45 ` syzbot
1 sibling, 0 replies; 4+ messages in thread
From: syzbot @ 2020-01-17 4:45 UTC (permalink / raw)
To: coreteam, davem, fw, kadlec, kadlec, kuznet, linux-kernel,
netdev, netfilter-devel, pablo, syzkaller-bugs, yoshfuji
syzbot has bisected this bug to:
commit 7c23b629a8085b11daccd68c62b5116ff498f84a
Author: Pablo Neira Ayuso <pablo@netfilter.org>
Date: Sun Jan 7 00:04:22 2018 +0000
netfilter: flow table support for the mixed IPv4/IPv6 family
bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=146472d1e00000
start commit: 51d69817 Merge tag 'platform-drivers-x86-v5.5-3' of git://..
git tree: upstream
final crash: https://syzkaller.appspot.com/x/report.txt?x=166472d1e00000
console output: https://syzkaller.appspot.com/x/log.txt?x=126472d1e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=d9290aeb7e6cf1c4
dashboard link: https://syzkaller.appspot.com/bug?extid=37a6804945a3a13b1572
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17241c76e00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13118315e00000
Reported-by: syzbot+37a6804945a3a13b1572@syzkaller.appspotmail.com
Fixes: 7c23b629a808 ("netfilter: flow table support for the mixed IPv4/IPv6
family")
For information about bisection process see: https://goo.gl/tpsmEJ#bisection
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2020-01-17 4:45 UTC | newest]
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2020-01-16 0:25 BUG: corrupted list in nf_tables_commit syzbot
2020-01-16 11:03 ` [PATCH nf] netfilter: nf_tables: fix flowtable list del corruption Florian Westphal
2020-01-16 13:54 ` Pablo Neira Ayuso
2020-01-17 4:45 ` BUG: corrupted list in nf_tables_commit syzbot
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