=====================================================
BUG: KMSAN: uninit-value in ip_tunnel_xmit+0x476/0x3610 net/ipv4/ip_tunnel.c:658
 ip_tunnel_xmit+0x476/0x3610 net/ipv4/ip_tunnel.c:658
 __gre_xmit net/ipv4/ip_gre.c:469 [inline]
 ipgre_xmit+0xd62/0xe70 net/ipv4/ip_gre.c:661
 __netdev_start_xmit include/linux/netdevice.h:4805 [inline]
 netdev_start_xmit include/linux/netdevice.h:4819 [inline]
 xmit_one+0x14e/0x5f0 net/core/dev.c:3590
 dev_hard_start_xmit+0xe5/0x370 net/core/dev.c:3606
 __dev_queue_xmit+0x1dec/0x31f0 net/core/dev.c:4255
 dev_queue_xmit include/linux/netdevice.h:2994 [inline]
 __bpf_tx_skb net/core/filter.c:2114 [inline]
 __bpf_redirect_no_mac net/core/filter.c:2139 [inline]
 __bpf_redirect+0xc93/0x1430 net/core/filter.c:2162
 ____bpf_clone_redirect net/core/filter.c:2429 [inline]
 bpf_clone_redirect+0x324/0x470 net/core/filter.c:2401
 ___bpf_prog_run+0x7ed/0xaee0 kernel/bpf/core.c:1852
 __bpf_prog_run512+0xc2/0x110 kernel/bpf/core.c:2077
 bpf_dispatcher_nop_func include/linux/bpf.h:869 [inline]
 __bpf_prog_run include/linux/filter.h:628 [inline]
 bpf_prog_run include/linux/filter.h:635 [inline]
 bpf_test_run+0x592/0xd20 net/bpf/test_run.c:402
 bpf_prog_test_run_skb+0x1625/0x20b0 net/bpf/test_run.c:1155
 bpf_prog_test_run+0x6a0/0x730 kernel/bpf/syscall.c:3591
 __sys_bpf+0x9e8/0xeb0 kernel/bpf/syscall.c:4935
 __do_sys_bpf kernel/bpf/syscall.c:5021 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5019 [inline]
 __ia32_sys_bpf+0x9c/0xe0 kernel/bpf/syscall.c:5019
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0x87/0xe0 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x70/0x82

Uninit was created at:
 slab_post_alloc_hook mm/slab.h:755 [inline]
 slab_alloc_node mm/slub.c:3258 [inline]
 __kmalloc_node_track_caller+0x86c/0x1230 mm/slub.c:4995
 kmalloc_reserve net/core/skbuff.c:354 [inline]
 pskb_expand_head+0x1aa/0x1a00 net/core/skbuff.c:1695
 skb_ensure_writable+0x3ce/0x460 net/core/skbuff.c:5609
 __bpf_try_make_writable net/core/filter.c:1655 [inline]
 bpf_try_make_writable net/core/filter.c:1661 [inline]
 bpf_try_make_head_writable net/core/filter.c:1669 [inline]
 ____bpf_clone_redirect net/core/filter.c:2423 [inline]
 bpf_clone_redirect+0x17b/0x470 net/core/filter.c:2401
 ___bpf_prog_run+0x7ed/0xaee0 kernel/bpf/core.c:1852
 __bpf_prog_run512+0xc2/0x110 kernel/bpf/core.c:2077
 bpf_dispatcher_nop_func include/linux/bpf.h:869 [inline]
 __bpf_prog_run include/linux/filter.h:628 [inline]
 bpf_prog_run include/linux/filter.h:635 [inline]
 bpf_test_run+0x592/0xd20 net/bpf/test_run.c:402
 bpf_prog_test_run_skb+0x1625/0x20b0 net/bpf/test_run.c:1155
 bpf_prog_test_run+0x6a0/0x730 kernel/bpf/syscall.c:3591
 __sys_bpf+0x9e8/0xeb0 kernel/bpf/syscall.c:4935
 __do_sys_bpf kernel/bpf/syscall.c:5021 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5019 [inline]
 __ia32_sys_bpf+0x9c/0xe0 kernel/bpf/syscall.c:5019
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0x87/0xe0 arch/x86/entry/common.c:178
 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:246
 entry_SYSENTER_compat_after_hwframe+0x70/0x82

CPU: 0 PID: 8568 Comm: syz-executor.3 Not tainted 5.19.0-rc8-syzkaller-32495-g3ea9edba19ef #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022
=====================================================