================================================================== BUG: KMSAN: uninit-value in __arch_swab32 arch/x86/include/uapi/asm/swab.h:10 [inline] BUG: KMSAN: uninit-value in __fswab32 include/uapi/linux/swab.h:59 [inline] BUG: KMSAN: uninit-value in gre_parse_header+0x1395/0x1690 net/ipv4/gre_demux.c:131 CPU: 0 PID: 11218 Comm: syz-executor078 Not tainted 5.3.0-rc3+ #17 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+0x162/0x2d0 mm/kmsan/kmsan_report.c:109 __msan_warning+0x75/0xe0 mm/kmsan/kmsan_instr.c:294 __arch_swab32 arch/x86/include/uapi/asm/swab.h:10 [inline] __fswab32 include/uapi/linux/swab.h:59 [inline] gre_parse_header+0x1395/0x1690 net/ipv4/gre_demux.c:131 gre_rcv+0x1cb/0x1900 net/ipv4/ip_gre.c:409 gre_rcv+0x2dd/0x3c0 net/ipv4/gre_demux.c:155 ip_protocol_deliver_rcu+0x722/0xbc0 net/ipv4/ip_input.c:204 ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline] NF_HOOK include/linux/netfilter.h:305 [inline] ip_local_deliver+0x62a/0x7c0 net/ipv4/ip_input.c:252 dst_input include/net/dst.h:442 [inline] ip_rcv_finish net/ipv4/ip_input.c:413 [inline] NF_HOOK include/linux/netfilter.h:305 [inline] ip_rcv+0x6c5/0x740 net/ipv4/ip_input.c:523 __netif_receive_skb_one_core net/core/dev.c:4999 [inline] __netif_receive_skb net/core/dev.c:5113 [inline] process_backlog+0xef5/0x1410 net/core/dev.c:5924 napi_poll net/core/dev.c:6347 [inline] net_rx_action+0x74b/0x1950 net/core/dev.c:6413 __do_softirq+0x4a1/0x83a kernel/softirq.c:293 do_softirq_own_stack+0x49/0x80 arch/x86/entry/entry_64.S:1091 do_softirq kernel/softirq.c:338 [inline] __local_bh_enable_ip+0x184/0x1d0 kernel/softirq.c:190 local_bh_enable+0x36/0x40 include/linux/bottom_half.h:32 rcu_read_unlock_bh include/linux/rcupdate.h:681 [inline] ip_finish_output2+0x20dc/0x25d0 net/ipv4/ip_output.c:229 __ip_finish_output+0xaf8/0xda0 net/ipv4/ip_output.c:308 ip_finish_output+0x2db/0x420 net/ipv4/ip_output.c:318 NF_HOOK_COND include/linux/netfilter.h:294 [inline] ip_output+0x541/0x610 net/ipv4/ip_output.c:432 dst_output include/net/dst.h:436 [inline] ip_local_out net/ipv4/ip_output.c:125 [inline] ip_send_skb net/ipv4/ip_output.c:1554 [inline] ip_push_pending_frames+0x243/0x460 net/ipv4/ip_output.c:1574 raw_sendmsg+0x2df8/0x46d0 net/ipv4/raw.c:672 inet_sendmsg+0x2d8/0x2e0 net/ipv4/af_inet.c:807 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg net/socket.c:657 [inline] ___sys_sendmsg+0x12c4/0x1590 net/socket.c:2311 __sys_sendmsg net/socket.c:2356 [inline] __do_sys_sendmsg net/socket.c:2365 [inline] __se_sys_sendmsg+0x305/0x460 net/socket.c:2363 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2363 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x63/0xe7 RIP: 0033:0x441a59 Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 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 10 fc ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007ffda6a5f768 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000441a59 RDX: 0000000000000000 RSI: 0000000020003d00 RDI: 0000000000000004 RBP: 00007ffda6a5f780 R08: 0000000001bbbbbb R09: 0000000001bbbbbb R10: 0000000000000044 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000402ff0 R14: 0000000000000000 R15: 0000000000000000 Uninit was stored to memory at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:187 [inline] kmsan_internal_chain_origin+0xcc/0x150 mm/kmsan/kmsan.c:345 kmsan_memcpy_memmove_metadata+0x819/0xa80 mm/kmsan/kmsan.c:278 kmsan_memcpy_metadata+0xb/0x10 mm/kmsan/kmsan.c:298 __msan_memcpy+0x56/0x70 mm/kmsan/kmsan_instr.c:129 pskb_expand_head+0x38a/0x19f0 net/core/skbuff.c:1637 __skb_cow include/linux/skbuff.h:3052 [inline] skb_cow_head include/linux/skbuff.h:3086 [inline] ip_tunnel_xmit+0x2971/0x3320 net/ipv4/ip_tunnel.c:811 __gre_xmit net/ipv4/ip_gre.c:444 [inline] erspan_xmit+0x1ef8/0x35c0 net/ipv4/ip_gre.c:679 __netdev_start_xmit include/linux/netdevice.h:4406 [inline] netdev_start_xmit include/linux/netdevice.h:4420 [inline] xmit_one net/core/dev.c:3280 [inline] dev_hard_start_xmit+0x51a/0xab0 net/core/dev.c:3296 sch_direct_xmit+0x56c/0x18c0 net/sched/sch_generic.c:309 __dev_xmit_skb net/core/dev.c:3477 [inline] __dev_queue_xmit+0x1e53/0x4270 net/core/dev.c:3838 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3902 neigh_resolve_output+0xab7/0xb50 net/core/neighbour.c:1490 neigh_output include/net/neighbour.h:511 [inline] ip_finish_output2+0x1a8e/0x25d0 net/ipv4/ip_output.c:228 __ip_finish_output+0xaf8/0xda0 net/ipv4/ip_output.c:308 ip_finish_output+0x2db/0x420 net/ipv4/ip_output.c:318 NF_HOOK_COND include/linux/netfilter.h:294 [inline] ip_output+0x541/0x610 net/ipv4/ip_output.c:432 dst_output include/net/dst.h:436 [inline] ip_local_out net/ipv4/ip_output.c:125 [inline] ip_send_skb net/ipv4/ip_output.c:1554 [inline] ip_push_pending_frames+0x243/0x460 net/ipv4/ip_output.c:1574 raw_sendmsg+0x2df8/0x46d0 net/ipv4/raw.c:672 inet_sendmsg+0x2d8/0x2e0 net/ipv4/af_inet.c:807 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg net/socket.c:657 [inline] ___sys_sendmsg+0x12c4/0x1590 net/socket.c:2311 __sys_sendmsg net/socket.c:2356 [inline] __do_sys_sendmsg net/socket.c:2365 [inline] __se_sys_sendmsg+0x305/0x460 net/socket.c:2363 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2363 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x63/0xe7 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:187 [inline] kmsan_internal_poison_shadow+0x53/0xa0 mm/kmsan/kmsan.c:146 kmsan_slab_alloc+0xaa/0x120 mm/kmsan/kmsan_hooks.c:175 slab_alloc_node mm/slub.c:2790 [inline] __kmalloc_node_track_caller+0xb55/0x1320 mm/slub.c:4388 __kmalloc_reserve net/core/skbuff.c:141 [inline] __alloc_skb+0x306/0xa10 net/core/skbuff.c:209 alloc_skb include/linux/skbuff.h:1056 [inline] __ip_append_data+0x3901/0x52f0 net/ipv4/ip_output.c:1094 ip_append_data+0x324/0x480 net/ipv4/ip_output.c:1309 raw_sendmsg+0x2d02/0x46d0 net/ipv4/raw.c:666 inet_sendmsg+0x2d8/0x2e0 net/ipv4/af_inet.c:807 sock_sendmsg_nosec net/socket.c:637 [inline] sock_sendmsg net/socket.c:657 [inline] ___sys_sendmsg+0x12c4/0x1590 net/socket.c:2311 __sys_sendmsg net/socket.c:2356 [inline] __do_sys_sendmsg net/socket.c:2365 [inline] __se_sys_sendmsg+0x305/0x460 net/socket.c:2363 __x64_sys_sendmsg+0x4a/0x70 net/socket.c:2363 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:297 entry_SYSCALL_64_after_hwframe+0x63/0xe7 ==================================================================