usercopy: kernel memory overwrite attempt detected to 0000000034a10221 (kmalloc-1024) (968 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: 0 PID: 3616 Comm: syz-executor3 Not tainted 4.15.0-rc5+ #171 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:ffff8801d9adf920 EFLAGS: 00010286 RAX: 0000000000000061 RBX: ffffffff8592bb60 RCX: 0000000000000000 RDX: 0000000000000061 RSI: ffffc90003528000 RDI: ffffed003b35bf18 RBP: ffff8801d9adfa10 R08: 0000000000000000 R09: 0000000000000000 R10: 000000002f27c913 R11: 0000000000000000 R12: ffffffff8592bb20 R13: ffff8801c8540dd0 R14: 00000000000003c8 R15: ffffea0007215000 FS: 00007f4f7cf1b700(0000) GS:ffff8801db200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f904ea22db8 CR3: 00000001d8040005 CR4: 00000000001606f0 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_from_user include/linux/uaccess.h:146 [inline] ___sys_sendmsg+0x59c/0x8b0 net/socket.c:1995 __sys_sendmmsg+0x1ee/0x620 net/socket.c:2108 SYSC_sendmmsg net/socket.c:2139 [inline] SyS_sendmmsg+0x35/0x60 net/socket.c:2134 entry_SYSCALL_64_fastpath+0x23/0x9a RIP: 0033:0x452ac9 RSP: 002b:00007f4f7cf1ac58 EFLAGS: 00000212 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 000000000071bea0 RCX: 0000000000452ac9 RDX: 0000000000000001 RSI: 0000000020571fc4 RDI: 0000000000000014 RBP: 00000000000000d9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000040000 R11: 0000000000000212 R12: 00000000006ef4f8 R13: 00000000ffffffff R14: 00007f4f7cf1b6d4 R15: 0000000000000000 Code: 48 0f 44 da e8 70 5b c0 ff 48 8b 85 28 ff ff ff 4d 89 f1 4c 89 e9 4c 89 e2 48 89 de 48 c7 c7 20 bc 92 85 49 89 c0 e8 e6 10 aa ff <0f> 0b 48 c7 c0 e0 b9 92 85 eb 96 48 c7 c0 20 ba 92 85 eb 8d 48 RIP: report_usercopy mm/usercopy.c:64 [inline] RSP: ffff8801d9adf920 RIP: __check_object_size+0x3a2/0x4f0 mm/usercopy.c:264 RSP: ffff8801d9adf920 ---[ end trace cbf50595c652a8c2 ]--- Kernel panic - not syncing: Fatal exception Dumping ftrace buffer: (ftrace buffer empty) Kernel Offset: disabled Rebooting in 86400 seconds..