=====================================================
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+0x1674/0x2960 net/ipv4/ip_gre.c:698
 __netdev_start_xmit include/linux/netdevice.h:4994 [inline]
 netdev_start_xmit include/linux/netdevice.h:5008 [inline]
 xmit_one+0x2f4/0x840 net/core/dev.c:3590
 dev_hard_start_xmit+0x186/0x440 net/core/dev.c:3606
 sch_direct_xmit+0x5f5/0x1400 net/sched/sch_generic.c:342
 __dev_xmit_skb+0x18a4/0x2900 net/core/dev.c:3817
 __dev_queue_xmit+0x1578/0x3290 net/core/dev.c:4194
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4262
 __bpf_tx_skb net/core/filter.c:2114 [inline]
 __bpf_redirect_common net/core/filter.c:2153 [inline]
 __bpf_redirect+0x15f0/0x1840 net/core/filter.c:2160
 ____bpf_clone_redirect net/core/filter.c:2429 [inline]
 bpf_clone_redirect+0x4a5/0x660 net/core/filter.c:2401
 ___bpf_prog_run+0x92d/0xb420 kernel/bpf/core.c:1558
 __bpf_prog_run512+0x121/0x180 kernel/bpf/core.c:1797
 bpf_dispatcher_nop_func include/linux/bpf.h:727 [inline]
 __bpf_prog_run include/linux/filter.h:626 [inline]
 bpf_prog_run include/linux/filter.h:633 [inline]
 bpf_test_run+0x762/0x1040 net/bpf/test_run.c:120
 bpf_prog_test_run_skb+0x15c9/0x2100 net/bpf/test_run.c:666
 bpf_prog_test_run+0x784/0x820 kernel/bpf/syscall.c:3349
 __sys_bpf+0xada/0x1230 kernel/bpf/syscall.c:4651
 __do_sys_bpf kernel/bpf/syscall.c:4737 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:4735 [inline]
 __ia32_sys_bpf+0xe1/0x130 kernel/bpf/syscall.c:4735
 do_syscall_32_irqs_on arch/x86/entry/common.c:114 [inline]
 __do_fast_syscall_32+0x96/0xf0 arch/x86/entry/common.c:180
 do_fast_syscall_32+0x34/0x70 arch/x86/entry/common.c:205
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:248
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

Uninit was created at:
 slab_post_alloc_hook mm/slab.h:524 [inline]
 slab_alloc_node mm/slub.c:3251 [inline]
 __kmalloc_node_track_caller+0xe0c/0x1510 mm/slub.c:4974
 kmalloc_reserve net/core/skbuff.c:354 [inline]
 pskb_expand_head+0x26a/0x1ca0 net/core/skbuff.c:1701
 __skb_cow include/linux/skbuff.h:3290 [inline]
 skb_cow_head include/linux/skbuff.h:3324 [inline]
 erspan_xmit+0xadd/0x2960 net/ipv4/ip_gre.c:685
 __netdev_start_xmit include/linux/netdevice.h:4994 [inline]
 netdev_start_xmit include/linux/netdevice.h:5008 [inline]
 xmit_one+0x2f4/0x840 net/core/dev.c:3590
 dev_hard_start_xmit+0x186/0x440 net/core/dev.c:3606
 sch_direct_xmit+0x5f5/0x1400 net/sched/sch_generic.c:342
 __dev_xmit_skb+0x18a4/0x2900 net/core/dev.c:3817
 __dev_queue_xmit+0x1578/0x3290 net/core/dev.c:4194
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:4262
 __bpf_tx_skb net/core/filter.c:2114 [inline]
 __bpf_redirect_common net/core/filter.c:2153 [inline]
 __bpf_redirect+0x15f0/0x1840 net/core/filter.c:2160
 ____bpf_clone_redirect net/core/filter.c:2429 [inline]
 bpf_clone_redirect+0x4a5/0x660 net/core/filter.c:2401
 ___bpf_prog_run+0x92d/0xb420 kernel/bpf/core.c:1558
 __bpf_prog_run512+0x121/0x180 kernel/bpf/core.c:1797
 bpf_dispatcher_nop_func include/linux/bpf.h:727 [inline]
 __bpf_prog_run include/linux/filter.h:626 [inline]
 bpf_prog_run include/linux/filter.h:633 [inline]
 bpf_test_run+0x762/0x1040 net/bpf/test_run.c:120
 bpf_prog_test_run_skb+0x15c9/0x2100 net/bpf/test_run.c:666
 bpf_prog_test_run+0x784/0x820 kernel/bpf/syscall.c:3349
 __sys_bpf+0xada/0x1230 kernel/bpf/syscall.c:4651
 __do_sys_bpf kernel/bpf/syscall.c:4737 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:4735 [inline]
 __ia32_sys_bpf+0xe1/0x130 kernel/bpf/syscall.c:4735
 do_syscall_32_irqs_on arch/x86/entry/common.c:114 [inline]
 __do_fast_syscall_32+0x96/0xf0 arch/x86/entry/common.c:180
 do_fast_syscall_32+0x34/0x70 arch/x86/entry/common.c:205
 do_SYSENTER_32+0x1b/0x20 arch/x86/entry/common.c:248
 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c

CPU: 0 PID: 16522 Comm: syz-executor.2 Not tainted 5.16.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
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