syzbot

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BUG: KMSAN: uninit-value in ip_route_output_key_hash_rcu+0x194/0x38d0 net/ipv4/route.c:2517
CPU: 1 PID: 4199 Comm: syz-executor.0 Not tainted 5.6.0-rc6-syzkaller #0
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+0x1c9/0x220 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:118
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 ip_route_output_key_hash_rcu+0x194/0x38d0 net/ipv4/route.c:2517
 ip_route_output_key_hash net/ipv4/route.c:2500 [inline]
 __ip_route_output_key include/net/route.h:126 [inline]
 ip_route_output_flow+0x1e1/0x3d0 net/ipv4/route.c:2763
 ipvlan_process_v4_outbound drivers/net/ipvlan/ipvlan_core.c:431 [inline]
 ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:525 [inline]
 ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:587 [inline]
 ipvlan_queue_xmit+0x1731/0x2f90 drivers/net/ipvlan/ipvlan_core.c:650
 ipvlan_start_xmit+0xa2/0x270 drivers/net/ipvlan/ipvlan_main.c:207
 __netdev_start_xmit include/linux/netdevice.h:4523 [inline]
 netdev_start_xmit include/linux/netdevice.h:4537 [inline]
 xmit_one net/core/dev.c:3477 [inline]
 dev_hard_start_xmit+0x531/0xab0 net/core/dev.c:3493
 __dev_queue_xmit+0x2f8d/0x3b20 net/core/dev.c:4052
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4085
 packet_snd net/packet/af_packet.c:2968 [inline]
 packet_sendmsg+0x8347/0x93b0 net/packet/af_packet.c:2993
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 sock_write_iter+0x6bc/0x6d0 net/socket.c:1004
 do_iter_readv_writev+0xa23/0xc70 include/linux/fs.h:1896
 do_iter_write+0x304/0xdc0 fs/read_write.c:998
 vfs_writev fs/read_write.c:1071 [inline]
 do_writev+0x42d/0x8f0 fs/read_write.c:1114
 __do_sys_writev fs/read_write.c:1187 [inline]
 __se_sys_writev+0x9b/0xb0 fs/read_write.c:1184
 __x64_sys_writev+0x4a/0x70 fs/read_write.c:1184
 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45c849
Code: ad b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f12efce2c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000014
RAX: ffffffffffffffda RBX: 00007f12efce36d4 RCX: 000000000045c849
RDX: 0000000000000001 RSI: 0000000020000280 RDI: 0000000000000003
RBP: 000000000076bf00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff
R13: 0000000000000d12 R14: 00000000004cb19d R15: 000000000076bf0c

Uninit was stored to memory at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_chain_origin+0xad/0x130 mm/kmsan/kmsan.c:310
 __msan_chain_origin+0x50/0x90 mm/kmsan/kmsan_instr.c:165
 ipvlan_process_v4_outbound drivers/net/ipvlan/ipvlan_core.c:422 [inline]
 ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:525 [inline]
 ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:587 [inline]
 ipvlan_queue_xmit+0x1fee/0x2f90 drivers/net/ipvlan/ipvlan_core.c:650
 ipvlan_start_xmit+0xa2/0x270 drivers/net/ipvlan/ipvlan_main.c:207
 __netdev_start_xmit include/linux/netdevice.h:4523 [inline]
 netdev_start_xmit include/linux/netdevice.h:4537 [inline]
 xmit_one net/core/dev.c:3477 [inline]
 dev_hard_start_xmit+0x531/0xab0 net/core/dev.c:3493
 __dev_queue_xmit+0x2f8d/0x3b20 net/core/dev.c:4052
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4085
 packet_snd net/packet/af_packet.c:2968 [inline]
 packet_sendmsg+0x8347/0x93b0 net/packet/af_packet.c:2993
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 sock_write_iter+0x6bc/0x6d0 net/socket.c:1004
 do_iter_readv_writev+0xa23/0xc70 include/linux/fs.h:1896
 do_iter_write+0x304/0xdc0 fs/read_write.c:998
 vfs_writev fs/read_write.c:1071 [inline]
 do_writev+0x42d/0x8f0 fs/read_write.c:1114
 __do_sys_writev fs/read_write.c:1187 [inline]
 __se_sys_writev+0x9b/0xb0 fs/read_write.c:1184
 __x64_sys_writev+0x4a/0x70 fs/read_write.c:1184
 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_poison_shadow+0x66/0xd0 mm/kmsan/kmsan.c:127
 kmsan_slab_alloc+0x8a/0xe0 mm/kmsan/kmsan_hooks.c:82
 slab_alloc_node mm/slub.c:2793 [inline]
 __kmalloc_node_track_caller+0xb40/0x1200 mm/slub.c:4401
 __kmalloc_reserve net/core/skbuff.c:142 [inline]
 __alloc_skb+0x2fd/0xac0 net/core/skbuff.c:210
 alloc_skb include/linux/skbuff.h:1081 [inline]
 alloc_skb_with_frags+0x18c/0xa70 net/core/skbuff.c:5764
 sock_alloc_send_pskb+0xada/0xc60 net/core/sock.c:2245
 packet_alloc_skb net/packet/af_packet.c:2816 [inline]
 packet_snd net/packet/af_packet.c:2911 [inline]
 packet_sendmsg+0x66a0/0x93b0 net/packet/af_packet.c:2993
 sock_sendmsg_nosec net/socket.c:652 [inline]
 sock_sendmsg net/socket.c:672 [inline]
 sock_write_iter+0x6bc/0x6d0 net/socket.c:1004
 do_iter_readv_writev+0xa23/0xc70 include/linux/fs.h:1896
 do_iter_write+0x304/0xdc0 fs/read_write.c:998
 vfs_writev fs/read_write.c:1071 [inline]
 do_writev+0x42d/0x8f0 fs/read_write.c:1114
 __do_sys_writev fs/read_write.c:1187 [inline]
 __se_sys_writev+0x9b/0xb0 fs/read_write.c:1184
 __x64_sys_writev+0x4a/0x70 fs/read_write.c:1184
 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
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