usercopy: kernel memory exposure attempt detected from 000000005c8dac94 (kmalloc-1024) (1024 bytes) ------------[ cut here ]------------ kernel BUG at mm/usercopy.c:72! invalid opcode: 0000 [#1] SMP KASAN Dumping ftrace buffer: (ftrace buffer empty) Modules linked in: CPU: 1 PID: 17676 Comm: syz-executor1 Not tainted 4.15.0-rc5+ #170 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:report_usercopy mm/usercopy.c:64 [inline] RIP: 0010:__check_object_size+0x3a2/0x4f0 mm/usercopy.c:264 RSP: 0018:ffff8801d0477858 EFLAGS: 00010286 RAX: 0000000000000063 RBX: ffffffff85529400 RCX: 0000000000000000 RDX: 0000000000000063 RSI: ffffc9000453f000 RDI: ffffed003a08eeff RBP: ffff8801d0477948 R08: 1ffff1003a08ee8d R09: 0000000000000000 R10: 00000000a53ad615 R11: 0000000000000000 R12: ffffffff855293c0 R13: ffff8801c5a0b250 R14: 0000000000000400 R15: ffffea0007168280 FS: 00007f25599f0700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000206c7000 CR3: 00000001d4e9f001 CR4: 00000000001606e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 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+0x105b/0x1fa0 net/bridge/br_ioctl.c:178 br_dev_ioctl+0x44/0xc0 net/bridge/br_ioctl.c:392 dev_ifsioc+0x333/0x9b0 net/core/dev_ioctl.c:354 dev_ioctl+0xa73/0xfb0 net/core/dev_ioctl.c:589 sock_ioctl+0x1da/0x440 net/socket.c:990 vfs_ioctl fs/ioctl.c:46 [inline] do_vfs_ioctl+0x1b1/0x1520 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: 0033:0x452ac9 RSP: 002b:00007f25599efc58 EFLAGS: 00000212 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f25599f0700 RCX: 0000000000452ac9 RDX: 0000000020b7efd8 RSI: 00000000000089f0 RDI: 0000000000000014 RBP: 0000000000a2f870 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000000 R13: 0000000000a2f7ef R14: 00007f25599f09c0 R15: 0000000000000002 Code: 48 0f 44 da e8 00 a0 c1 ff 48 8b 85 28 ff ff ff 4d 89 f1 4c 89 e9 4c 89 e2 48 89 de 48 c7 c7 40 94 52 85 49 89 c0 e8 c6 59 ab ff <0f> 0b 48 c7 c0 00 92 52 85 eb 96 48 c7 c0 40 92 52 85 eb 8d 48 RIP: report_usercopy mm/usercopy.c:64 [inline] RSP: ffff8801d0477858 RIP: __check_object_size+0x3a2/0x4f0 mm/usercopy.c:264 RSP: ffff8801d0477858 ---[ end trace 129c95efdcdee2a8 ]--- Kernel panic - not syncing: Fatal exception Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled Rebooting in 86400 seconds..