kernel msg: ebtables bug: please report to author: Valid hook without chain
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BUG: KMSAN: uninit-value in copy_to_user include/linux/uaccess.h:184 [inline]
BUG: KMSAN: uninit-value in move_addr_to_user+0x32e/0x530 net/socket.c:226
CPU: 0 PID: 8977 Comm: syz-executor1 Not tainted 4.17.0-rc3+ #92
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 kmsan_internal_check_memory+0x135/0x1e0 mm/kmsan/kmsan.c:1157
 kmsan_copy_to_user+0x75/0x160 mm/kmsan/kmsan.c:1199
 copy_to_user include/linux/uaccess.h:184 [inline]
 move_addr_to_user+0x32e/0x530 net/socket.c:226
 ___sys_recvmsg+0x4e2/0x810 net/socket.c:2285
 __sys_recvmsg net/socket.c:2328 [inline]
 __do_sys_recvmsg net/socket.c:2338 [inline]
 __se_sys_recvmsg net/socket.c:2335 [inline]
 __x64_sys_recvmsg+0x325/0x460 net/socket.c:2335
 do_syscall_64+0x154/0x220 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x4559d9
RSP: 002b:00007fa4efeedc68 EFLAGS: 00000246 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 00007fa4efeee6d4 RCX: 00000000004559d9
RDX: 0000000000002000 RSI: 0000000020000d00 RDI: 0000000000000013
RBP: 000000000072bea0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000549 R14: 00000000006fbf78 R15: 0000000000000000

Local variable description: ----addr@___sys_recvmsg
Variable was created at:
 ___sys_recvmsg+0xd5/0x810 net/socket.c:2246
 __sys_recvmsg net/socket.c:2328 [inline]
 __do_sys_recvmsg net/socket.c:2338 [inline]
 __se_sys_recvmsg net/socket.c:2335 [inline]
 __x64_sys_recvmsg+0x325/0x460 net/socket.c:2335

Byte 19 of 32 is uninitialized
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