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BUG: KMSAN: uninit-value in erspan_build_header+0x167/0x2f0 include/net/erspan.h:197
 erspan_build_header+0x167/0x2f0 include/net/erspan.h:197
 erspan_xmit+0x10a9/0x1dc0 net/ipv4/ip_gre.c:736
 __netdev_start_xmit include/linux/netdevice.h:5368 [inline]
 netdev_start_xmit include/linux/netdevice.h:5377 [inline]
 xmit_one net/core/dev.c:3888 [inline]
 dev_hard_start_xmit+0x22f/0xa80 net/core/dev.c:3904
 sch_direct_xmit+0x3b2/0xcf0 net/sched/sch_generic.c:372
 __dev_xmit_skb net/core/dev.c:4209 [inline]
 __dev_queue_xmit+0x3592/0x5a00 net/core/dev.c:4831
 dev_queue_xmit include/linux/netdevice.h:3418 [inline]
 __bpf_tx_skb net/core/filter.c:2156 [inline]
 __bpf_redirect_common net/core/filter.c:2200 [inline]
 __bpf_redirect+0x162e/0x1760 net/core/filter.c:2207
 ____bpf_clone_redirect net/core/filter.c:2497 [inline]
 bpf_clone_redirect+0x4a6/0x6c0 net/core/filter.c:2460
 ___bpf_prog_run+0x13e8/0xeab0 kernel/bpf/core.c:2078
 __bpf_prog_run32+0xc2/0xf0 kernel/bpf/core.c:2371
 bpf_dispatcher_nop_func include/linux/bpf.h:1402 [inline]
 __bpf_prog_run include/linux/filter.h:722 [inline]
 bpf_prog_run include/linux/filter.h:729 [inline]
 bpf_test_run+0x493/0xdf0 net/bpf/test_run.c:423
 bpf_prog_test_run_skb+0x2988/0x35f0 net/bpf/test_run.c:1192
 bpf_prog_test_run+0x5bb/0x9f0 kernel/bpf/syscall.c:4742
 __sys_bpf+0x925/0xee0 kernel/bpf/syscall.c:6292
 __do_sys_bpf kernel/bpf/syscall.c:6387 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:6385 [inline]
 __ia32_sys_bpf+0xa4/0xf0 kernel/bpf/syscall.c:6385
 ia32_sys_call+0x33e7/0x4360 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+0x195/0x470 arch/x86/entry/syscall_32.c:307
 do_fast_syscall_32+0x37/0x80 arch/x86/entry/syscall_32.c:332
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:370
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4577 [inline]
 slab_alloc_node mm/slub.c:4899 [inline]
 kmem_cache_alloc_node_noprof+0x3cd/0x12c0 mm/slub.c:4951
 kmalloc_reserve net/core/skbuff.c:613 [inline]
 pskb_expand_head+0x2f3/0x1a40 net/core/skbuff.c:2303
 __skb_cow include/linux/skbuff.h:3881 [inline]
 skb_cow_head include/linux/skbuff.h:3915 [inline]
 erspan_xmit+0x97a/0x1dc0 net/ipv4/ip_gre.c:722
 __netdev_start_xmit include/linux/netdevice.h:5368 [inline]
 netdev_start_xmit include/linux/netdevice.h:5377 [inline]
 xmit_one net/core/dev.c:3888 [inline]
 dev_hard_start_xmit+0x22f/0xa80 net/core/dev.c:3904
 sch_direct_xmit+0x3b2/0xcf0 net/sched/sch_generic.c:372
 __dev_xmit_skb net/core/dev.c:4209 [inline]
 __dev_queue_xmit+0x3592/0x5a00 net/core/dev.c:4831
 dev_queue_xmit include/linux/netdevice.h:3418 [inline]
 __bpf_tx_skb net/core/filter.c:2156 [inline]
 __bpf_redirect_common net/core/filter.c:2200 [inline]
 __bpf_redirect+0x162e/0x1760 net/core/filter.c:2207
 ____bpf_clone_redirect net/core/filter.c:2497 [inline]
 bpf_clone_redirect+0x4a6/0x6c0 net/core/filter.c:2460
 ___bpf_prog_run+0x13e8/0xeab0 kernel/bpf/core.c:2078
 __bpf_prog_run32+0xc2/0xf0 kernel/bpf/core.c:2371
 bpf_dispatcher_nop_func include/linux/bpf.h:1402 [inline]
 __bpf_prog_run include/linux/filter.h:722 [inline]
 bpf_prog_run include/linux/filter.h:729 [inline]
 bpf_test_run+0x493/0xdf0 net/bpf/test_run.c:423
 bpf_prog_test_run_skb+0x2988/0x35f0 net/bpf/test_run.c:1192
 bpf_prog_test_run+0x5bb/0x9f0 kernel/bpf/syscall.c:4742
 __sys_bpf+0x925/0xee0 kernel/bpf/syscall.c:6292
 __do_sys_bpf kernel/bpf/syscall.c:6387 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:6385 [inline]
 __ia32_sys_bpf+0xa4/0xf0 kernel/bpf/syscall.c:6385
 ia32_sys_call+0x33e7/0x4360 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+0x195/0x470 arch/x86/entry/syscall_32.c:307
 do_fast_syscall_32+0x37/0x80 arch/x86/entry/syscall_32.c:332
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:370
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

CPU: 1 UID: 0 PID: 6714 Comm: syz.4.146 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
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