device nr0 entered promiscuous mode ===================================================== BUG: KMSAN: uninit-value in __skb_flow_dissect+0x207e/0x7a40 net/core/flow_dissector.c:957 CPU: 1 PID: 16300 Comm: syz-executor.1 Not tainted 5.4.0-rc3+ #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+0x191/0x1f0 lib/dump_stack.c:113 kmsan_report+0x128/0x220 mm/kmsan/kmsan_report.c:108 __msan_warning+0x73/0xe0 mm/kmsan/kmsan_instr.c:245 __skb_flow_dissect+0x207e/0x7a40 net/core/flow_dissector.c:957 __skb_get_hash_symmetric+0x108/0x260 net/core/flow_dissector.c:1523 fanout_demux_hash net/packet/af_packet.c:1314 [inline] packet_rcv_fanout+0xa73/0x2550 net/packet/af_packet.c:1429 deliver_skb net/core/dev.c:1969 [inline] __netif_receive_skb_core+0x1cab/0x51a0 net/core/dev.c:4896 __netif_receive_skb_one_core net/core/dev.c:5008 [inline] __netif_receive_skb net/core/dev.c:5124 [inline] netif_receive_skb_internal+0x3cc/0xc20 net/core/dev.c:5214 netif_receive_skb+0x1da/0x3a0 net/core/dev.c:5273 tun_rx_batched drivers/net/tun.c:1553 [inline] tun_get_user+0x6c44/0x6f70 drivers/net/tun.c:1993 tun_chr_write_iter+0x1f2/0x360 drivers/net/tun.c:2022 call_write_iter include/linux/fs.h:1895 [inline] new_sync_write fs/read_write.c:483 [inline] __vfs_write+0xa2c/0xcb0 fs/read_write.c:496 vfs_write+0x481/0x920 fs/read_write.c:558 ksys_write+0x265/0x430 fs/read_write.c:611 __do_sys_write fs/read_write.c:623 [inline] __se_sys_write+0x92/0xb0 fs/read_write.c:620 __x64_sys_write+0x4a/0x70 fs/read_write.c:620 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x459ef9 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:00007fa5e774dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000459ef9 RDX: 000000000000fdef RSI: 00000000200000c0 RDI: 0000000000000003 RBP: 000000000075bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa5e774e6d4 R13: 00000000004ca516 R14: 00000000004e23d8 R15: 00000000ffffffff Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:151 [inline] kmsan_internal_chain_origin+0xbd/0x180 mm/kmsan/kmsan.c:319 __msan_chain_origin+0x6b/0xd0 mm/kmsan/kmsan_instr.c:179 __skb_flow_dissect+0x30ee/0x7a40 net/core/flow_dissector.c:1060 __skb_get_hash_symmetric+0x108/0x260 net/core/flow_dissector.c:1523 fanout_demux_hash net/packet/af_packet.c:1314 [inline] packet_rcv_fanout+0xa73/0x2550 net/packet/af_packet.c:1429 deliver_skb net/core/dev.c:1969 [inline] __netif_receive_skb_core+0x1cab/0x51a0 net/core/dev.c:4896 __netif_receive_skb_one_core net/core/dev.c:5008 [inline] __netif_receive_skb net/core/dev.c:5124 [inline] netif_receive_skb_internal+0x3cc/0xc20 net/core/dev.c:5214 netif_receive_skb+0x1da/0x3a0 net/core/dev.c:5273 tun_rx_batched drivers/net/tun.c:1553 [inline] tun_get_user+0x6c44/0x6f70 drivers/net/tun.c:1993 tun_chr_write_iter+0x1f2/0x360 drivers/net/tun.c:2022 call_write_iter include/linux/fs.h:1895 [inline] new_sync_write fs/read_write.c:483 [inline] __vfs_write+0xa2c/0xcb0 fs/read_write.c:496 vfs_write+0x481/0x920 fs/read_write.c:558 ksys_write+0x265/0x430 fs/read_write.c:611 __do_sys_write fs/read_write.c:623 [inline] __se_sys_write+0x92/0xb0 fs/read_write.c:620 __x64_sys_write+0x4a/0x70 fs/read_write.c:620 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:151 [inline] kmsan_internal_chain_origin+0xbd/0x180 mm/kmsan/kmsan.c:319 __msan_chain_origin+0x6b/0xd0 mm/kmsan/kmsan_instr.c:179 vlan_set_encap_proto include/linux/skbuff.h:1587 [inline] skb_vlan_untag+0x6bc/0xd20 net/core/skbuff.c:5329 __netif_receive_skb_core+0x833/0x51a0 net/core/dev.c:4855 __netif_receive_skb_one_core net/core/dev.c:5008 [inline] __netif_receive_skb net/core/dev.c:5124 [inline] netif_receive_skb_internal+0x3cc/0xc20 net/core/dev.c:5214 netif_receive_skb+0x1da/0x3a0 net/core/dev.c:5273 tun_rx_batched drivers/net/tun.c:1553 [inline] tun_get_user+0x6c44/0x6f70 drivers/net/tun.c:1993 tun_chr_write_iter+0x1f2/0x360 drivers/net/tun.c:2022 call_write_iter include/linux/fs.h:1895 [inline] new_sync_write fs/read_write.c:483 [inline] __vfs_write+0xa2c/0xcb0 fs/read_write.c:496 vfs_write+0x481/0x920 fs/read_write.c:558 ksys_write+0x265/0x430 fs/read_write.c:611 __do_sys_write fs/read_write.c:623 [inline] __se_sys_write+0x92/0xb0 fs/read_write.c:620 __x64_sys_write+0x4a/0x70 fs/read_write.c:620 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:151 [inline] kmsan_internal_poison_shadow+0x60/0x120 mm/kmsan/kmsan.c:134 kmsan_slab_alloc+0xaa/0x120 mm/kmsan/kmsan_hooks.c:88 slab_alloc_node mm/slub.c:2792 [inline] __kmalloc_node_track_caller+0xda2/0x13d0 mm/slub.c:4398 __kmalloc_reserve net/core/skbuff.c:141 [inline] __alloc_skb+0x306/0xa10 net/core/skbuff.c:209 alloc_skb include/linux/skbuff.h:1050 [inline] alloc_skb_with_frags+0x18c/0xa80 net/core/skbuff.c:5659 sock_alloc_send_pskb+0xafd/0x10a0 net/core/sock.c:2240 tun_alloc_skb drivers/net/tun.c:1529 [inline] tun_get_user+0x1132/0x6f70 drivers/net/tun.c:1843 tun_chr_write_iter+0x1f2/0x360 drivers/net/tun.c:2022 call_write_iter include/linux/fs.h:1895 [inline] new_sync_write fs/read_write.c:483 [inline] __vfs_write+0xa2c/0xcb0 fs/read_write.c:496 vfs_write+0x481/0x920 fs/read_write.c:558 ksys_write+0x265/0x430 fs/read_write.c:611 __do_sys_write fs/read_write.c:623 [inline] __se_sys_write+0x92/0xb0 fs/read_write.c:620 __x64_sys_write+0x4a/0x70 fs/read_write.c:620 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:291 entry_SYSCALL_64_after_hwframe+0x63/0xe7 =====================================================