===================================================== BUG: KMSAN: uninit-value in ip_tunnel_xmit+0x585/0x3a40 net/ipv4/ip_tunnel.c:663 CPU: 1 PID: 12092 Comm: syz-executor.3 Not tainted 5.9.0-rc8-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+0x21c/0x280 lib/dump_stack.c:118 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:122 __msan_warning+0x5f/0xa0 mm/kmsan/kmsan_instr.c:201 ip_tunnel_xmit+0x585/0x3a40 net/ipv4/ip_tunnel.c:663 __gre_xmit net/ipv4/ip_gre.c:466 [inline] ipgre_xmit+0x1261/0x1380 net/ipv4/ip_gre.c:650 __netdev_start_xmit include/linux/netdevice.h:4636 [inline] netdev_start_xmit include/linux/netdevice.h:4650 [inline] xmit_one+0x1fc/0x760 net/core/dev.c:3561 dev_hard_start_xmit net/core/dev.c:3577 [inline] __dev_queue_xmit+0x3310/0x4490 net/core/dev.c:4136 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4169 packet_snd net/packet/af_packet.c:2989 [inline] packet_sendmsg+0x86e9/0x99c0 net/packet/af_packet.c:3014 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg net/socket.c:671 [inline] ____sys_sendmsg+0xc7a/0x1240 net/socket.c:2353 ___sys_sendmsg net/socket.c:2407 [inline] __sys_sendmmsg+0x835/0x1010 net/socket.c:2490 __compat_sys_sendmmsg net/compat.c:361 [inline] __do_compat_sys_sendmmsg net/compat.c:368 [inline] __se_compat_sys_sendmmsg+0xcd/0xf0 net/compat.c:365 __ia32_compat_sys_sendmmsg+0x56/0x70 net/compat.c:365 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline] __do_fast_syscall_32+0x129/0x180 arch/x86/entry/common.c:139 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7fe9549 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 eb 0d 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000f55e30cc EFLAGS: 00000296 ORIG_RAX: 0000000000000159 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020001f80 RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Uninit was created at: kmsan_save_stack_with_flags mm/kmsan/kmsan.c:129 [inline] kmsan_internal_poison_shadow+0x5c/0xf0 mm/kmsan/kmsan.c:112 kmsan_slab_alloc+0x8d/0xe0 mm/kmsan/kmsan_hooks.c:80 slab_alloc_node mm/slub.c:2903 [inline] __kmalloc_node_track_caller+0x7de/0x1320 mm/slub.c:4507 __kmalloc_reserve net/core/skbuff.c:142 [inline] __alloc_skb+0x309/0xae0 net/core/skbuff.c:210 alloc_skb include/linux/skbuff.h:1094 [inline] alloc_skb_with_frags+0x1f3/0xc20 net/core/skbuff.c:5771 sock_alloc_send_pskb+0xc73/0xe40 net/core/sock.c:2348 packet_alloc_skb net/packet/af_packet.c:2837 [inline] packet_snd net/packet/af_packet.c:2932 [inline] packet_sendmsg+0x6a93/0x99c0 net/packet/af_packet.c:3014 sock_sendmsg_nosec net/socket.c:651 [inline] sock_sendmsg net/socket.c:671 [inline] ____sys_sendmsg+0xc7a/0x1240 net/socket.c:2353 ___sys_sendmsg net/socket.c:2407 [inline] __sys_sendmmsg+0x835/0x1010 net/socket.c:2490 __compat_sys_sendmmsg net/compat.c:361 [inline] __do_compat_sys_sendmmsg net/compat.c:368 [inline] __se_compat_sys_sendmmsg+0xcd/0xf0 net/compat.c:365 __ia32_compat_sys_sendmmsg+0x56/0x70 net/compat.c:365 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline] __do_fast_syscall_32+0x129/0x180 arch/x86/entry/common.c:139 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c =====================================================