Messages in this thread | | | From | Dmitry Vyukov <> | Date | Wed, 19 Feb 2020 09:34:11 +0100 | Subject | Re: BUG: using smp_processor_id() in preemptible [ADDR] code: syz-executor |
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On Wed, Feb 19, 2020 at 9:31 AM Dmitry Vyukov <dvyukov@google.com> wrote: > > On Sun, Jun 30, 2019 at 7:19 AM Hillf Danton <hdanton@sina.com> wrote: > > > > > > Hello, > > > > On Sat, 29 Jun 2019 08:47:06 -0700 (PDT) > > > syzbot found the following crash on: > > > > > > HEAD commit: ee7dd773 sis900: remove TxIDLE > > > git tree: net-next > > > console output: https://syzkaller.appspot.com/x/log.txt?x=17ceb9a9a00000 > > > kernel config: https://syzkaller.appspot.com/x/.config?x=7ac9edef4d37e5fb > > > dashboard link: https://syzkaller.appspot.com/bug?extid=1a68504d96cd17b33a05 > > > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > > > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=119b2a13a00000 > > > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=13127bada00000 > > > > > > The bug was bisected to: > > > > Hm... I doubt it is e9c1a793210f ("tipc: add dst_cache support for udp media") > > based on one of the lines dumped: > > > > > tipc_udp_xmit.isra.0+0xc4/0xb80 net/tipc/udp_media.c:164 > > > > > > And getting the local bottom half disabled looks like a teaspoon of > > cough syrup. > > --- > > > > --- a/net/tipc/udp_media.c > > +++ b/net/tipc/udp_media.c > > @@ -224,6 +224,8 @@ static int tipc_udp_send_msg(struct net *net, struct sk_buff *skb, > > struct udp_bearer *ub; > > int err = 0; > > > > + local_bh_disable(); > > + > > if (skb_headroom(skb) < UDP_MIN_HEADROOM) { > > err = pskb_expand_head(skb, UDP_MIN_HEADROOM, 0, GFP_ATOMIC); > > if (err) > > @@ -237,9 +239,12 @@ static int tipc_udp_send_msg(struct net *net, struct sk_buff *skb, > > goto out; > > } > > > > - if (addr->broadcast != TIPC_REPLICAST_SUPPORT) > > - return tipc_udp_xmit(net, skb, ub, src, dst, > > + if (addr->broadcast != TIPC_REPLICAST_SUPPORT) { > > + err = tipc_udp_xmit(net, skb, ub, src, dst, > > &ub->rcast.dst_cache); > > + local_bh_enable(); > > + return err; > > + } > > > > /* Replicast, send an skb to each configured IP address */ > > list_for_each_entry_rcu(rcast, &ub->rcast.list, list) { > > @@ -259,6 +264,7 @@ static int tipc_udp_send_msg(struct net *net, struct sk_buff *skb, > > err = 0; > > out: > > kfree_skb(skb); > > + local_bh_enable(); > > return err; > > } > > > > -- > > > > > commit 52dfae5c85a4c1078e9f1d5e8947d4a25f73dd81 > > > Author: Jon Maloy <jon.maloy@ericsson.com> > > > Date: Thu Mar 22 19:42:52 2018 +0000 > > > > > > tipc: obtain node identity from interface by default > > What is the fate of this fix? > There is also another fix for this pending for half a year as far as I can tell. > > This is one of the top crashes and it prevents most other kernel > testing from happening. All kernels just crash on this right away.
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+jmaloy new email address
> > > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=160ad903a00000 > > > final crash: https://syzkaller.appspot.com/x/report.txt?x=150ad903a00000 > > > console output: https://syzkaller.appspot.com/x/log.txt?x=110ad903a00000 > > > > > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > > > Reported-by: syzbot+1a68504d96cd17b33a05@syzkaller.appspotmail.com > > > Fixes: 52dfae5c85a4 ("tipc: obtain node identity from interface by default") > > > > > > Started in network mode > > > Own node identity 7f000001, cluster identity 4711 > > > New replicast peer: 172.20.20.22 > > > check_preemption_disabled: 3 callbacks suppressed > > > BUG: using smp_processor_id() in preemptible [00000000] code: > > > syz-executor834/8612 > > > caller is dst_cache_get+0x3d/0xb0 net/core/dst_cache.c:68 > > > CPU: 0 PID: 8612 Comm: syz-executor834 Not tainted 5.2.0-rc6+ #48 > > > 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+0x172/0x1f0 lib/dump_stack.c:113 > > > check_preemption_disabled lib/smp_processor_id.c:47 [inline] > > > debug_smp_processor_id+0x251/0x280 lib/smp_processor_id.c:57 > > > dst_cache_get+0x3d/0xb0 net/core/dst_cache.c:68 > > > tipc_udp_xmit.isra.0+0xc4/0xb80 net/tipc/udp_media.c:164 > > > tipc_udp_send_msg+0x29a/0x4b0 net/tipc/udp_media.c:254 > > > tipc_bearer_xmit_skb+0x16c/0x360 net/tipc/bearer.c:503 > > > tipc_enable_bearer+0xabe/0xd20 net/tipc/bearer.c:328 > > > __tipc_nl_bearer_enable+0x2de/0x3a0 net/tipc/bearer.c:899 > > > tipc_nl_bearer_enable+0x23/0x40 net/tipc/bearer.c:907 > > > genl_family_rcv_msg+0x74b/0xf90 net/netlink/genetlink.c:629 > > > genl_rcv_msg+0xca/0x16c net/netlink/genetlink.c:654 > > > netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 > > > genl_rcv+0x29/0x40 net/netlink/genetlink.c:665 > > > netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] > > > netlink_unicast+0x531/0x710 net/netlink/af_netlink.c:1328 > > > netlink_sendmsg+0x8ae/0xd70 net/netlink/af_netlink.c:1917 > > > sock_sendmsg_nosec net/socket.c:646 [inline] > > > sock_sendmsg+0xd7/0x130 net/socket.c:665 > > > ___sys_sendmsg+0x803/0x920 net/socket.c:2286 > > > __sys_sendmsg+0x105/0x1d0 net/socket.c:2324 > > > __do_sys_sendmsg net/socket.c:2333 [inline] > > > __se_sys_sendmsg net/socket.c:2331 [inline] > > > __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2331 > > > do_syscall_64+0xfd/0x680 arch/x86/entry/common.c:301 > > > entry_SYSCALL_64_after_hwframe+0x49/0xbe > > > RIP: 0033:0x444679 > > > Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 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 1b d8 fb ff c3 66 2e 0f 1f 84 00 00 00 00 > > > RSP: 002b:00007fff0201a8b8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e > > > RAX: ffffffffffffffda RBX: 00000000004002e0 RCX: 0000000000444679 > > > RDX: 0000000000000000 RSI: 0000000020000580 RDI: 0000000000000003 > > > RBP: 00000000006cf018 R08: 0000000000000001 R09: 00000000004002e0 > > > R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000402320 > > > R13: 00000000004023b0 R14: 0000000000000000 R15: 0000000000 > > > > > > > > > --- > > > 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. > > > For information about bisection process see: https://goo.gl/tpsmEJ#bisection > > > syzbot can test patches for this bug, for details see: > > > https://goo.gl/tpsmEJ#testing-patches > > > > > > > > > -- > > 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/000000000000a40746058c784ef3%40google.com. > > For more options, visit https://groups.google.com/d/optout.
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