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BUG: KMSAN: uninit-value in ip_tunnel_xmit+0x8fa/0x4230 net/ipv4/ip_tunnel.c:661
 ip_tunnel_xmit+0x8fa/0x4230 net/ipv4/ip_tunnel.c:661
 __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:4819 [inline]
 netdev_start_xmit include/linux/netdevice.h:4833 [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:4256
 dev_queue_xmit include/linux/netdevice.h:3008 [inline]
 __bpf_tx_skb net/core/filter.c:2115 [inline]
 __bpf_redirect_no_mac net/core/filter.c:2140 [inline]
 __bpf_redirect+0xcda/0x13b0 net/core/filter.c:2163
 ____bpf_clone_redirect net/core/filter.c:2430 [inline]
 bpf_clone_redirect+0x324/0x470 net/core/filter.c:2402
 ___bpf_prog_run+0x7ed/0xaee0 kernel/bpf/core.c:1813
 __bpf_prog_run512+0xc2/0x110 kernel/bpf/core.c:2038
 bpf_dispatcher_nop_func include/linux/bpf.h:903 [inline]
 __bpf_prog_run include/linux/filter.h:594 [inline]
 bpf_prog_run include/linux/filter.h:601 [inline]
 bpf_test_run+0x592/0xd20 net/bpf/test_run.c:402
 bpf_prog_test_run_skb+0x1625/0x20b0 net/bpf/test_run.c:1141
 bpf_prog_test_run+0x6a0/0x730 kernel/bpf/syscall.c:3620
 __sys_bpf+0x88d/0xe70 kernel/bpf/syscall.c:4971
 __do_sys_bpf kernel/bpf/syscall.c:5057 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5055 [inline]
 __ia32_sys_bpf+0x9c/0xe0 kernel/bpf/syscall.c:5055
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0xa2/0x100 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:732 [inline]
 slab_alloc_node mm/slub.c:3258 [inline]
 __kmalloc_node_track_caller+0x814/0x1250 mm/slub.c:4970
 kmalloc_reserve net/core/skbuff.c:362 [inline]
 pskb_expand_head+0x24a/0x1a80 net/core/skbuff.c:1729
 skb_ensure_writable+0x3ce/0x460 net/core/skbuff.c:5638
 __bpf_try_make_writable net/core/filter.c:1656 [inline]
 bpf_try_make_writable net/core/filter.c:1662 [inline]
 bpf_try_make_head_writable net/core/filter.c:1670 [inline]
 ____bpf_clone_redirect net/core/filter.c:2424 [inline]
 bpf_clone_redirect+0x17b/0x470 net/core/filter.c:2402
 ___bpf_prog_run+0x7ed/0xaee0 kernel/bpf/core.c:1813
 __bpf_prog_run512+0xc2/0x110 kernel/bpf/core.c:2038
 bpf_dispatcher_nop_func include/linux/bpf.h:903 [inline]
 __bpf_prog_run include/linux/filter.h:594 [inline]
 bpf_prog_run include/linux/filter.h:601 [inline]
 bpf_test_run+0x592/0xd20 net/bpf/test_run.c:402
 bpf_prog_test_run_skb+0x1625/0x20b0 net/bpf/test_run.c:1141
 bpf_prog_test_run+0x6a0/0x730 kernel/bpf/syscall.c:3620
 __sys_bpf+0x88d/0xe70 kernel/bpf/syscall.c:4971
 __do_sys_bpf kernel/bpf/syscall.c:5057 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5055 [inline]
 __ia32_sys_bpf+0x9c/0xe0 kernel/bpf/syscall.c:5055
 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
 __do_fast_syscall_32+0xa2/0x100 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: 12109 Comm: syz-executor.2 Not tainted 6.0.0-rc5-syzkaller-48539-g523d2ce66d07 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
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