=====================================================
BUG: KMSAN: uninit-value in erspan_build_header+0x171/0x2f0 include/net/erspan.h:197
 erspan_build_header+0x171/0x2f0 include/net/erspan.h:197
 erspan_xmit+0x1256/0x1cd0 net/ipv4/ip_gre.c:733
 __netdev_start_xmit include/linux/netdevice.h:5203 [inline]
 netdev_start_xmit include/linux/netdevice.h:5212 [inline]
 xmit_one net/core/dev.c:3776 [inline]
 dev_hard_start_xmit+0x296/0xa40 net/core/dev.c:3792
 sch_direct_xmit+0x399/0xd40 net/sched/sch_generic.c:343
 __dev_xmit_skb net/core/dev.c:4018 [inline]
 __dev_queue_xmit+0x30c8/0x57e0 net/core/dev.c:4595
 dev_queue_xmit include/linux/netdevice.h:3350 [inline]
 __bpf_tx_skb net/core/filter.c:2143 [inline]
 __bpf_redirect_common net/core/filter.c:2187 [inline]
 __bpf_redirect+0x1514/0x1690 net/core/filter.c:2194
 ____bpf_clone_redirect net/core/filter.c:2468 [inline]
 bpf_clone_redirect+0x37f/0x500 net/core/filter.c:2438
 ___bpf_prog_run+0x12fd/0xf0b0 kernel/bpf/core.c:2018
 __bpf_prog_run512+0xc5/0xf0 kernel/bpf/core.c:2313
 bpf_dispatcher_nop_func include/linux/bpf.h:1316 [inline]
 __bpf_prog_run include/linux/filter.h:718 [inline]
 bpf_prog_run include/linux/filter.h:725 [inline]
 bpf_test_run+0x546/0xd20 net/bpf/test_run.c:434
 bpf_prog_test_run_skb+0x1906/0x25b0 net/bpf/test_run.c:1093
 bpf_prog_test_run+0x5e5/0xa30 kernel/bpf/syscall.c:4427
 __sys_bpf+0x6ce/0xdf0 kernel/bpf/syscall.c:5852
 __do_sys_bpf kernel/bpf/syscall.c:5941 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5939 [inline]
 __ia32_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5939
 ia32_sys_call+0x2126/0x41f0 arch/x86/include/generated/asm/syscalls_32.h:358
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb0/0x110 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:369
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4167 [inline]
 slab_alloc_node mm/slub.c:4210 [inline]
 kmem_cache_alloc_node_noprof+0x921/0xe10 mm/slub.c:4262
 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:577
 pskb_expand_head+0x21f/0x1c10 net/core/skbuff.c:2247
 __skb_cow include/linux/skbuff.h:3772 [inline]
 skb_cow_head include/linux/skbuff.h:3806 [inline]
 erspan_xmit+0x8e4/0x1cd0 net/ipv4/ip_gre.c:719
 __netdev_start_xmit include/linux/netdevice.h:5203 [inline]
 netdev_start_xmit include/linux/netdevice.h:5212 [inline]
 xmit_one net/core/dev.c:3776 [inline]
 dev_hard_start_xmit+0x296/0xa40 net/core/dev.c:3792
 sch_direct_xmit+0x399/0xd40 net/sched/sch_generic.c:343
 __dev_xmit_skb net/core/dev.c:4018 [inline]
 __dev_queue_xmit+0x30c8/0x57e0 net/core/dev.c:4595
 dev_queue_xmit include/linux/netdevice.h:3350 [inline]
 __bpf_tx_skb net/core/filter.c:2143 [inline]
 __bpf_redirect_common net/core/filter.c:2187 [inline]
 __bpf_redirect+0x1514/0x1690 net/core/filter.c:2194
 ____bpf_clone_redirect net/core/filter.c:2468 [inline]
 bpf_clone_redirect+0x37f/0x500 net/core/filter.c:2438
 ___bpf_prog_run+0x12fd/0xf0b0 kernel/bpf/core.c:2018
 __bpf_prog_run512+0xc5/0xf0 kernel/bpf/core.c:2313
 bpf_dispatcher_nop_func include/linux/bpf.h:1316 [inline]
 __bpf_prog_run include/linux/filter.h:718 [inline]
 bpf_prog_run include/linux/filter.h:725 [inline]
 bpf_test_run+0x546/0xd20 net/bpf/test_run.c:434
 bpf_prog_test_run_skb+0x1906/0x25b0 net/bpf/test_run.c:1093
 bpf_prog_test_run+0x5e5/0xa30 kernel/bpf/syscall.c:4427
 __sys_bpf+0x6ce/0xdf0 kernel/bpf/syscall.c:5852
 __do_sys_bpf kernel/bpf/syscall.c:5941 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5939 [inline]
 __ia32_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5939
 ia32_sys_call+0x2126/0x41f0 arch/x86/include/generated/asm/syscalls_32.h:358
 do_syscall_32_irqs_on arch/x86/entry/syscall_32.c:83 [inline]
 __do_fast_syscall_32+0xb0/0x110 arch/x86/entry/syscall_32.c:306
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:369
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

CPU: 0 UID: 0 PID: 8755 Comm: syz.8.492 Not tainted 6.15.0-rc3-syzkaller-00032-ga79be02bba5c #0 PREEMPT(undef) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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