Hello, syzbot found the following crash on: HEAD commit: 36a44bcd Merge branch 'bnxt_en-shutdown-and-kexec-kdump-re.. git tree: net console output: https://syzkaller.appspot.com/x/log.txt?x=15b5774ee00000 kernel config: https://syzkaller.appspot.com/x/.config?x=768cc3d3e277cc16 dashboard link: https://syzkaller.appspot.com/bug?extid=84484ccebdd4e5451d91 compiler: gcc (GCC) 9.0.0 20181231 (experimental) syz repro: https://syzkaller.appspot.com/x/repro.syz?x=100eda7ee00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=11c3fdd9e00000 The bug was bisected to: commit cbd34da7dc9afd521e0bea5e7d12701f4a9da7c7 Author: Christoph Hellwig <hch@xxxxxx> Date: Fri Jul 12 03:57:28 2019 +0000 mm: move the powerpc hugepd code to mm/gup.c bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=15ea4265e00000 final crash: https://syzkaller.appspot.com/x/report.txt?x=17ea4265e00000 console output: https://syzkaller.appspot.com/x/log.txt?x=13ea4265e00000 IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: syzbot+84484ccebdd4e5451d91@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: cbd34da7dc9a ("mm: move the powerpc hugepd code to mm/gup.c") infiniband syz1: RDMA CMA: cma_listen_on_dev, error -98 netlink: 'syz-executor837': attribute type 1 has an invalid length. netlink: 21 bytes leftover after parsing attributes in process `syz-executor837'. general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] CPU: 0 PID: 9928 Comm: syz-executor837 Not tainted 5.6.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__list_del_entry_valid+0x22/0xf5 lib/list_debug.c:42 Code: 0e fe 48 8b 75 e8 eb b2 48 b8 00 00 00 00 00 fc ff df 55 48 89 e5 41 56 49 89 fe 48 83 c7 08 48 89 fa 41 55 48 c1 ea 03 41 54 <80> 3c 02 00 0f 85 a1 00 00 00 4c 89 f2 4d 8b 66 08 48 b8 00 00 00 RSP: 0018:ffffc900053d7440 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: ffffffff87b4e490 RCX: ffffffff815c1ba9 RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000008 RBP: ffffc900053d7458 R08: 0000000000000004 R09: fffff52000a7ae7b R10: fffff52000a7ae7a R11: 0000000000000003 R12: 0000000000000000 R13: 0000000000000008 R14: 0000000000000000 R15: ffffffff8a98b880 FS: 0000000000ea3880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020003028 CR3: 0000000091874000 CR4: 00000000001406f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: __list_del_entry include/linux/list.h:132 [inline] list_del_init include/linux/list.h:204 [inline] smc_ib_remove_dev+0x52/0x2e0 net/smc/smc_ib.c:578 remove_client_context+0xc7/0x120 drivers/infiniband/core/device.c:724 disable_device+0x14c/0x230 drivers/infiniband/core/device.c:1268 __ib_unregister_device+0x9c/0x190 drivers/infiniband/core/device.c:1435 ib_unregister_device_and_put+0x5f/0x80 drivers/infiniband/core/device.c:1498 nldev_dellink+0x222/0x340 drivers/infiniband/core/nldev.c:1568 rdma_nl_rcv_msg drivers/infiniband/core/netlink.c:195 [inline] rdma_nl_rcv_skb drivers/infiniband/core/netlink.c:239 [inline] rdma_nl_rcv+0x5d9/0x980 drivers/infiniband/core/netlink.c:259 netlink_unicast_kernel net/netlink/af_netlink.c:1303 [inline] netlink_unicast+0x59e/0x7e0 net/netlink/af_netlink.c:1329 netlink_sendmsg+0x91c/0xea0 net/netlink/af_netlink.c:1918 sock_sendmsg_nosec net/socket.c:652 [inline] sock_sendmsg+0xd7/0x130 net/socket.c:672 __sys_sendto+0x262/0x380 net/socket.c:1998 __do_sys_sendto net/socket.c:2010 [inline] __se_sys_sendto net/socket.c:2006 [inline] __x64_sys_sendto+0xe1/0x1a0 net/socket.c:2006 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x4404d9 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 fb 13 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffdb793fb28 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 00000000004404d9 RDX: 0000000000010a73 RSI: 0000000020000000 RDI: 0000000000000004 RBP: 00000000006ca018 R08: 0000000000000000 R09: 4b6ae4f95a5de35b R10: 00000000000008c0 R11: 0000000000000246 R12: 0000000000401d60 R13: 0000000000401df0 R14: 0000000000000000 R15: 0000000000000000 Modules linked in: ---[ end trace 79db9bfdece7383f ]--- RIP: 0010:__list_del_entry_valid+0x22/0xf5 lib/list_debug.c:42 Code: 0e fe 48 8b 75 e8 eb b2 48 b8 00 00 00 00 00 fc ff df 55 48 89 e5 41 56 49 89 fe 48 83 c7 08 48 89 fa 41 55 48 c1 ea 03 41 54 <80> 3c 02 00 0f 85 a1 00 00 00 4c 89 f2 4d 8b 66 08 48 b8 00 00 00 RSP: 0018:ffffc900053d7440 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: ffffffff87b4e490 RCX: ffffffff815c1ba9 RDX: 0000000000000001 RSI: 0000000000000004 RDI: 0000000000000008 RBP: ffffc900053d7458 R08: 0000000000000004 R09: fffff52000a7ae7b R10: fffff52000a7ae7a R11: 0000000000000003 R12: 0000000000000000 R13: 0000000000000008 R14: 0000000000000000 R15: ffffffff8a98b880 FS: 0000000000ea3880(0000) GS:ffff8880ae800000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020003028 CR3: 0000000091874000 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@xxxxxxxxxxxxxxxx. 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
