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BUG: KMSAN: uninit-value in packet_set_ring+0x1254/0x3870 net/packet/af_packet.c:4249
CPU: 0 PID: 7218 Comm: syz-executor0 Not tainted 4.16.0+ #87
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:17 [inline]
 dump_stack+0x185/0x1d0 lib/dump_stack.c:53
 kmsan_report+0x142/0x240 mm/kmsan/kmsan.c:1067
 __msan_warning_32+0x6c/0xb0 mm/kmsan/kmsan_instr.c:683
 packet_set_ring+0x1254/0x3870 net/packet/af_packet.c:4249
 packet_setsockopt+0x12c6/0x5a90 net/packet/af_packet.c:3662
 SYSC_setsockopt+0x4b8/0x570 net/socket.c:1849
 SyS_setsockopt+0x76/0xa0 net/socket.c:1828
 do_syscall_64+0x309/0x430 arch/x86/entry/common.c:287
 entry_SYSCALL_64_after_hwframe+0x3d/0xa2
RIP: 0033:0x455389
RSP: 002b:00007fd1cb38ec68 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007fd1cb38f6d4 RCX: 0000000000455389
RDX: 0000000000000005 RSI: 0000000000000107 RDI: 0000000000000014
RBP: 000000000072bf58 R08: 00000000000000c5 R09: 0000000000000000
R10: 0000000020001000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000517 R14: 00000000006faac8 R15: 0000000000000001

Local variable description: ----req_u@packet_setsockopt
Variable was created at:
 packet_setsockopt+0x13f/0x5a90 net/packet/af_packet.c:3612
 SYSC_setsockopt+0x4b8/0x570 net/socket.c:1849
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