=====================================================
BUG: KMSAN: uninit-value in erspan_build_header+0x1ec/0x470 include/net/erspan.h:194
 erspan_build_header+0x1ec/0x470 include/net/erspan.h:194
 erspan_xmit+0x1682/0x2980 net/ipv4/ip_gre.c:699
 __netdev_start_xmit include/linux/netdevice.h:4778 [inline]
 netdev_start_xmit include/linux/netdevice.h:4792 [inline]
 xmit_one+0x2f4/0x840 net/core/dev.c:3532
 dev_hard_start_xmit+0x186/0x440 net/core/dev.c:3548
 sch_direct_xmit+0x5f5/0x1400 net/sched/sch_generic.c:342
 __dev_xmit_skb+0x18a4/0x2920 net/core/dev.c:3759
 __dev_queue_xmit+0x1599/0x3500 net/core/dev.c:4141
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4209
 __bpf_tx_skb net/core/filter.c:2113 [inline]
 __bpf_redirect_common net/core/filter.c:2152 [inline]
 __bpf_redirect+0x18ec/0x1ad0 net/core/filter.c:2159
 ____bpf_clone_redirect net/core/filter.c:2428 [inline]
 bpf_clone_redirect+0x4a5/0x670 net/core/filter.c:2400
 ___bpf_prog_run+0x92d/0xb420 kernel/bpf/core.c:1835
 __bpf_prog_run512+0x121/0x180 kernel/bpf/core.c:2075
 bpf_dispatcher_nop_func include/linux/bpf.h:804 [inline]
 __bpf_prog_run include/linux/filter.h:628 [inline]
 bpf_prog_run include/linux/filter.h:635 [inline]
 bpf_test_run+0x76b/0x1080 net/bpf/test_run.c:401
 bpf_prog_test_run_skb+0x175e/0x2270 net/bpf/test_run.c:1110
 bpf_prog_test_run+0x784/0x820 kernel/bpf/syscall.c:3369
 __sys_bpf+0xadd/0x1240 kernel/bpf/syscall.c:4681
 __do_sys_bpf kernel/bpf/syscall.c:4767 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:4765 [inline]
 __ia32_sys_bpf+0xe1/0x130 kernel/bpf/syscall.c:4765
 do_syscall_32_irqs_on arch/x86/entry/common.c:113 [inline]
 __do_fast_syscall_32+0x96/0xf0 arch/x86/entry/common.c:179
 do_fast_syscall_32+0x34/0x70 arch/x86/entry/common.c:204
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:247
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Uninit was created at:
 slab_post_alloc_hook mm/slab.h:754 [inline]
 slab_alloc_node mm/slub.c:3231 [inline]
 __kmalloc_node_track_caller+0xde3/0x14f0 mm/slub.c:4962
 kmalloc_reserve net/core/skbuff.c:354 [inline]
 pskb_expand_head+0x26d/0x1fd0 net/core/skbuff.c:1700
 __skb_cow include/linux/skbuff.h:3476 [inline]
 skb_cow_head include/linux/skbuff.h:3510 [inline]
 erspan_xmit+0xaeb/0x2980 net/ipv4/ip_gre.c:686
 __netdev_start_xmit include/linux/netdevice.h:4778 [inline]
 netdev_start_xmit include/linux/netdevice.h:4792 [inline]
 xmit_one+0x2f4/0x840 net/core/dev.c:3532
 dev_hard_start_xmit+0x186/0x440 net/core/dev.c:3548
 sch_direct_xmit+0x5f5/0x1400 net/sched/sch_generic.c:342
 __dev_xmit_skb+0x18a4/0x2920 net/core/dev.c:3759
 __dev_queue_xmit+0x1599/0x3500 net/core/dev.c:4141
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4209
 __bpf_tx_skb net/core/filter.c:2113 [inline]
 __bpf_redirect_common net/core/filter.c:2152 [inline]
 __bpf_redirect+0x18ec/0x1ad0 net/core/filter.c:2159
 ____bpf_clone_redirect net/core/filter.c:2428 [inline]
 bpf_clone_redirect+0x4a5/0x670 net/core/filter.c:2400
 ___bpf_prog_run+0x92d/0xb420 kernel/bpf/core.c:1835
 __bpf_prog_run512+0x121/0x180 kernel/bpf/core.c:2075
 bpf_dispatcher_nop_func include/linux/bpf.h:804 [inline]
 __bpf_prog_run include/linux/filter.h:628 [inline]
 bpf_prog_run include/linux/filter.h:635 [inline]
 bpf_test_run+0x76b/0x1080 net/bpf/test_run.c:401
 bpf_prog_test_run_skb+0x175e/0x2270 net/bpf/test_run.c:1110
 bpf_prog_test_run+0x784/0x820 kernel/bpf/syscall.c:3369
 __sys_bpf+0xadd/0x1240 kernel/bpf/syscall.c:4681
 __do_sys_bpf kernel/bpf/syscall.c:4767 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:4765 [inline]
 __ia32_sys_bpf+0xe1/0x130 kernel/bpf/syscall.c:4765
 do_syscall_32_irqs_on arch/x86/entry/common.c:113 [inline]
 __do_fast_syscall_32+0x96/0xf0 arch/x86/entry/common.c:179
 do_fast_syscall_32+0x34/0x70 arch/x86/entry/common.c:204
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:247
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

CPU: 1 PID: 5935 Comm: syz-executor.4 Not tainted 5.18.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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