device gre0 entered promiscuous mode usercopy: kernel memory exposure attempt detected from 00000000a6830059 (kmalloc-1024) (1024 bytes) ------------[ cut here ]------------ kernel BUG at mm/usercopy.c:84! invalid opcode: 0000 [#1] SMP Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 1 PID: 28799 Comm: syz-executor4 Not tainted 4.15.0-rc3-next-20171214+ #67 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:report_usercopy mm/usercopy.c:76 [inline] RIP: 0010:__check_object_size+0x1e2/0x250 mm/usercopy.c:276 RSP: 0018:ffffc9000116fc50 EFLAGS: 00010286 RAX: 0000000000000063 RBX: ffffffff82e6518f RCX: ffffffff8123dede RDX: 0000000000004c58 RSI: ffffc900050ed000 RDI: ffff88021fd136f8 RBP: ffffc9000116fc88 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff880216bb6050 R13: 0000000000000400 R14: 0000000000000001 R15: ffffffff82eda864 FS: 00007f61a06bc700(0000) GS:ffff88021fd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020a5afd8 CR3: 000000020f8a9000 CR4: 00000000001406e0 Call Trace: check_object_size include/linux/thread_info.h:112 [inline] check_copy_size include/linux/thread_info.h:143 [inline] copy_to_user include/linux/uaccess.h:154 [inline] old_dev_ioctl.isra.1+0x21d/0x9a0 net/bridge/br_ioctl.c:178 br_dev_ioctl+0x3f/0xa0 net/bridge/br_ioctl.c:392 dev_ifsioc+0x175/0x520 net/core/dev_ioctl.c:354 dev_ioctl+0x548/0x7a0 net/core/dev_ioctl.c:589 sock_ioctl+0x150/0x320 net/socket.c:998 vfs_ioctl fs/ioctl.c:46 [inline] do_vfs_ioctl+0xaf/0x840 fs/ioctl.c:686 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:692 entry_SYSCALL_64_fastpath+0x1f/0x96 RIP: 0033:0x452a39 RSP: 002b:00007f61a06bbc58 EFLAGS: 00000212 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f61a06bc700 RCX: 0000000000452a39 RDX: 0000000020a59fd8 RSI: 00000000000089f0 RDI: 0000000000000014 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000000 R13: 0000000000a6f7ff R14: 00007f61a06bc9c0 R15: 0000000000000000 Code: 7b e5 82 48 0f 44 da e8 8d 82 eb ff 48 8b 45 d0 4d 89 e9 4c 89 e1 4c 89 fa 48 89 de 48 c7 c7 a8 51 e6 82 49 89 c0 e8 76 b7 e3 ff <0f> 0b 48 c7 c0 43 51 e6 82 eb a1 48 c7 c0 53 51 e6 82 eb 98 48 RIP: report_usercopy mm/usercopy.c:76 [inline] RSP: ffffc9000116fc50 RIP: __check_object_size+0x1e2/0x250 mm/usercopy.c:276 RSP: ffffc9000116fc50 ---[ end trace 5fadb883cda020dc ]--- Kernel panic - not syncing: Fatal exception Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled Rebooting in 86400 seconds..