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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+0x143f/0x1750 net/ipv4/gre_demux.c:131
CPU: 0 PID: 11562 Comm: syz-executor144 Not tainted 5.5.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x220 lib/dump_stack.c:118
 kmsan_report+0xf8/0x1e0 mm/kmsan/kmsan_report.c:118
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 __arch_swab32 arch/x86/include/uapi/asm/swab.h:10 [inline]
 __fswab32 include/uapi/linux/swab.h:59 [inline]
 gre_parse_header+0x143f/0x1750 net/ipv4/gre_demux.c:131
 gre_rcv+0x1cb/0x1930 net/ipv4/ip_gre.c:413
 gre_rcv+0x2dd/0x3c0 net/ipv4/gre_demux.c:155
 ip_protocol_deliver_rcu+0x70f/0xbd0 net/ipv4/ip_input.c:204
 ip_local_deliver_finish net/ipv4/ip_input.c:231 [inline]
 NF_HOOK include/linux/netfilter.h:307 [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:428 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 ip_rcv+0x6cf/0x750 net/ipv4/ip_input.c:538
 __netif_receive_skb_one_core net/core/dev.c:5150 [inline]
 __netif_receive_skb net/core/dev.c:5264 [inline]
 process_backlog+0xece/0x13c0 net/core/dev.c:6095
 napi_poll net/core/dev.c:6532 [inline]
 net_rx_action+0x7a6/0x1aa0 net/core/dev.c:6600
 __do_softirq+0x4a1/0x83a kernel/softirq.c:293
 do_softirq_own_stack+0x49/0x80 arch/x86/entry/entry_64.S:1091
 </IRQ>
 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:706 [inline]
 ip_finish_output2+0x20ec/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:296 [inline]
 ip_output+0x593/0x680 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_queue_xmit+0x1caf/0x21f0 net/ipv4/ip_output.c:532
 ip_queue_xmit+0xcc/0xf0 include/net/ip.h:237
 __tcp_transmit_skb+0x4387/0x5ec0 net/ipv4/tcp_output.c:1170
 tcp_transmit_skb net/ipv4/tcp_output.c:1186 [inline]
 tcp_connect+0x3da5/0x67a0 net/ipv4/tcp_output.c:3583
 tcp_v6_connect+0x25cc/0x27c0 net/ipv6/tcp_ipv6.c:329
 __inet_stream_connect+0x2f5/0x1350 net/ipv4/af_inet.c:655
 inet_stream_connect+0x101/0x180 net/ipv4/af_inet.c:719
 __sys_connect_file net/socket.c:1844 [inline]
 __sys_connect+0x6f3/0x770 net/socket.c:1861
 __do_sys_connect net/socket.c:1872 [inline]
 __se_sys_connect+0x8d/0xb0 net/socket.c:1869
 __x64_sys_connect+0x4a/0x70 net/socket.c:1869
 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x442ad9
Code: e8 0c e8 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 00 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 6b 09 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffc3234a718 EFLAGS: 00000246 ORIG_RAX: 000000000000002a
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000442ad9
RDX: 000000000000001c RSI: 0000000020000140 RDI: 0000000000000004
RBP: 000000000001bf0f R08: 0000000100000000 R09: 0000000100000000
R10: 0000000100000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000403960 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:144 [inline]
 kmsan_internal_poison_shadow+0x5c/0xf0 mm/kmsan/kmsan.c:127
 kmsan_slab_alloc+0x8b/0xe0 mm/kmsan/kmsan_hooks.c:82
 slab_alloc_node mm/slub.c:2774 [inline]
 __kmalloc_node_track_caller+0xe47/0x11f0 mm/slub.c:4382
 __kmalloc_reserve net/core/skbuff.c:141 [inline]
 __alloc_skb+0x309/0xa50 net/core/skbuff.c:209
 alloc_skb_fclone include/linux/skbuff.h:1099 [inline]
 sk_stream_alloc_skb+0x359/0x11c0 net/ipv4/tcp.c:877
 tcp_connect+0x2358/0x67a0 net/ipv4/tcp_output.c:3570
 tcp_v6_connect+0x25cc/0x27c0 net/ipv6/tcp_ipv6.c:329
 __inet_stream_connect+0x2f5/0x1350 net/ipv4/af_inet.c:655
 inet_stream_connect+0x101/0x180 net/ipv4/af_inet.c:719
 __sys_connect_file net/socket.c:1844 [inline]
 __sys_connect+0x6f3/0x770 net/socket.c:1861
 __do_sys_connect net/socket.c:1872 [inline]
 __se_sys_connect+0x8d/0xb0 net/socket.c:1869
 __x64_sys_connect+0x4a/0x70 net/socket.c:1869
 do_syscall_64+0xb6/0x160 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
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