On Wed, Oct 2, 2019 at 3:56 PM syzbot <syzbot+3f3e5e77d793c7a6fe6c@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote: > > Hello, > > syzbot found the following crash on: > > HEAD commit: a32db7e1 Add linux-next specific files for 20191002 > git tree: linux-next > console output: https://syzkaller.appspot.com/x/log.txt?x=175ab7cd600000 > kernel config: https://syzkaller.appspot.com/x/.config?x=599cf05035799eef > dashboard link: https://syzkaller.appspot.com/bug?extid=3f3e5e77d793c7a6fe6c > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=12f8b943600000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16981a25600000 > > The bug was bisected to: > > commit 84da111de0b4be15bd500deff773f5116f39f7be > Author: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> > Date: Sat Sep 21 17:07:42 2019 +0000 > > Merge tag 'for-linus-hmm' of > git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma > > bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=17c55847600000 > final crash: https://syzkaller.appspot.com/x/report.txt?x=14255847600000 > console output: https://syzkaller.appspot.com/x/log.txt?x=10255847600000 > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+3f3e5e77d793c7a6fe6c@xxxxxxxxxxxxxxxxxxxxxxxxx > Fixes: 84da111de0b4 ("Merge tag 'for-linus-hmm' of > git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma") > > RSP: 002b:00007fff0ba6c998 EFLAGS: 00000246 ORIG_RAX: 000000000000002e > RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004424a9 > RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000003 > RBP: 0000000000000000 R08: 0000000000000002 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffffff > R13: 0000000000000004 R14: 0000000000000000 R15: 0000000000000000 > kasan: CONFIG_KASAN_INLINE enabled > kasan: GPF could be caused by NULL-ptr deref or user memory access > general protection fault: 0000 [#1] PREEMPT SMP KASAN > CPU: 1 PID: 8605 Comm: syz-executor330 Not tainted 5.4.0-rc1-next-20191002 > #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS > Google 01/01/2011 > RIP: 0010:veth_stats_rx drivers/net/veth.c:322 [inline] > RIP: 0010:veth_get_stats64+0x523/0x900 drivers/net/veth.c:356 > Code: 89 85 60 ff ff ff e8 6c 74 31 fd 49 63 c7 48 69 c0 c0 02 00 00 48 03 > 85 60 ff ff ff 48 8d b8 a0 01 00 00 48 89 fa 48 c1 ea 03 <42> 80 3c 32 00 > 0f 85 c9 02 00 00 48 8d b8 a8 01 00 00 48 8b 90 a0 > RSP: 0018:ffff88809996ed00 EFLAGS: 00010202 > RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff84418daf > RDX: 0000000000000034 RSI: ffffffff84418e04 RDI: 00000000000001a0 > RBP: ffff88809996ede0 R08: ffff888093182180 R09: ffffed1013202d6a > R10: ffffed1013202d69 R11: ffff888099016b4f R12: 0000000000000000 > R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000 > FS: 0000000001f4a880(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000020000140 CR3: 000000009a80b000 CR4: 00000000001406e0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > dev_get_stats+0x8e/0x280 net/core/dev.c:9220 > rtnl_fill_stats+0x4d/0xac0 net/core/rtnetlink.c:1191 > rtnl_fill_ifinfo+0x10ad/0x3af0 net/core/rtnetlink.c:1717 > rtmsg_ifinfo_build_skb+0xc9/0x1a0 net/core/rtnetlink.c:3635 > rtmsg_ifinfo_event.part.0+0x43/0xe0 net/core/rtnetlink.c:3667 > rtmsg_ifinfo_event net/core/rtnetlink.c:3678 [inline] > rtmsg_ifinfo+0x8d/0xa0 net/core/rtnetlink.c:3676 > __dev_notify_flags+0x235/0x2c0 net/core/dev.c:7757 > rtnl_configure_link+0x175/0x250 net/core/rtnetlink.c:2968 > __rtnl_newlink+0x10c4/0x16d0 net/core/rtnetlink.c:3285 > rtnl_newlink+0x69/0xa0 net/core/rtnetlink.c:3325 > rtnetlink_rcv_msg+0x463/0xb00 net/core/rtnetlink.c:5386 > netlink_rcv_skb+0x177/0x450 net/netlink/af_netlink.c:2477 > rtnetlink_rcv+0x1d/0x30 net/core/rtnetlink.c:5404 > netlink_unicast_kernel net/netlink/af_netlink.c:1302 [inline] > netlink_unicast+0x531/0x710 net/netlink/af_netlink.c:1328 > netlink_sendmsg+0x8a5/0xd60 net/netlink/af_netlink.c:1917 > sock_sendmsg_nosec net/socket.c:638 [inline] > sock_sendmsg+0xd7/0x130 net/socket.c:658 > ___sys_sendmsg+0x803/0x920 net/socket.c:2312 > __sys_sendmsg+0x105/0x1d0 net/socket.c:2357 > __do_sys_sendmsg net/socket.c:2366 [inline] > __se_sys_sendmsg net/socket.c:2364 [inline] > __x64_sys_sendmsg+0x78/0xb0 net/socket.c:2364 > do_syscall_64+0xfa/0x760 arch/x86/entry/common.c:290 > entry_SYSCALL_64_after_hwframe+0x49/0xbe > RIP: 0033:0x4424a9 > Code: e8 9c 07 03 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 3b 0a fc ff c3 66 2e 0f 1f 84 00 00 00 00 > RSP: 002b:00007fff0ba6c998 EFLAGS: 00000246 ORIG_RAX: 000000000000002e > RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000004424a9 > RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000003 > RBP: 0000000000000000 R08: 0000000000000002 R09: 0000000000000000 > R10: 0000000000000000 R11: 0000000000000246 R12: ffffffffffffffff > R13: 0000000000000004 R14: 0000000000000000 R15: 0000000000000000 > Modules linked in: > ---[ end trace cc6dec8a4962bfff ]--- > RIP: 0010:veth_stats_rx drivers/net/veth.c:322 [inline] > RIP: 0010:veth_get_stats64+0x523/0x900 drivers/net/veth.c:356 > Code: 89 85 60 ff ff ff e8 6c 74 31 fd 49 63 c7 48 69 c0 c0 02 00 00 48 03 > 85 60 ff ff ff 48 8d b8 a0 01 00 00 48 89 fa 48 c1 ea 03 <42> 80 3c 32 00 > 0f 85 c9 02 00 00 48 8d b8 a8 01 00 00 48 8b 90 a0 > RSP: 0018:ffff88809996ed00 EFLAGS: 00010202 > RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff84418daf > RDX: 0000000000000034 RSI: ffffffff84418e04 RDI: 00000000000001a0 > RBP: ffff88809996ede0 R08: ffff888093182180 R09: ffffed1013202d6a > R10: ffffed1013202d69 R11: ffff888099016b4f R12: 0000000000000000 > R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000 > FS: 0000000001f4a880(0000) GS:ffff8880ae900000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000020000140 CR3: 000000009a80b000 CR4: 00000000001406e0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Syzbot CC:ed a lot of people directly on this report. Perhaps because of the bisection? Specific to the report: I think this may be introduced with the alternative names for network interfaces patchset. The reproducer fails on 76c9ac0ee878 net: rtnetlink: add possibility to use alternative names as message handle passes on be2644aac3e1 tcp: add ipv6_addr_v4mapped_loopback() helper Leaving 76c9ac0ee878 net: rtnetlink: add possibility to use alternative names as message handle cc6090e985d7 net: rtnetlink: introduce helper to get net_device instance by ifname 7af12cba4ef0 net: rtnetlink: unify the code in __rtnl_newlink get dev with the rest 88f4fb0c7496 net: rtnetlink: put alternative names to getlink message 36fbf1e52bd3 net: rtnetlink: add linkprop commands to add and delete alternative ifnames ff92741270bf net: introduce name_node struct to be used in hashlist 6958c97a488c net: procfs: use index hashlist instead of name hashlist be2
