=====================================================
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+0x10b0/0x1ce0 net/ipv4/ip_gre.c:733
 __netdev_start_xmit include/linux/netdevice.h:5248 [inline]
 netdev_start_xmit include/linux/netdevice.h:5257 [inline]
 xmit_one net/core/dev.c:3845 [inline]
 dev_hard_start_xmit+0x22f/0xa30 net/core/dev.c:3861
 sch_direct_xmit+0x3b2/0xcf0 net/sched/sch_generic.c:344
 __dev_xmit_skb net/core/dev.c:4152 [inline]
 __dev_queue_xmit+0x3588/0x5e60 net/core/dev.c:4729
 dev_queue_xmit include/linux/netdevice.h:3365 [inline]
 __bpf_tx_skb net/core/filter.c:2153 [inline]
 __bpf_redirect_common net/core/filter.c:2197 [inline]
 __bpf_redirect+0x162d/0x1760 net/core/filter.c:2204
 ____bpf_clone_redirect net/core/filter.c:2478 [inline]
 bpf_clone_redirect+0x366/0x530 net/core/filter.c:2448
 ___bpf_prog_run+0x1294/0xeba0 kernel/bpf/core.c:2000
 __bpf_prog_run32+0xc2/0xf0 kernel/bpf/core.c:2294
 bpf_dispatcher_nop_func include/linux/bpf.h:1350 [inline]
 __bpf_prog_run include/linux/filter.h:721 [inline]
 bpf_prog_run include/linux/filter.h:728 [inline]
 bpf_test_run+0x498/0xb90 net/bpf/test_run.c:434
 bpf_prog_test_run_skb+0x18c1/0x26a0 net/bpf/test_run.c:1102
 bpf_prog_test_run+0x5bf/0xa40 kernel/bpf/syscall.c:4673
 __sys_bpf+0x873/0xeb0 kernel/bpf/syscall.c:6152
 __do_sys_bpf kernel/bpf/syscall.c:6244 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:6242 [inline]
 __ia32_sys_bpf+0xa4/0xf0 kernel/bpf/syscall.c:6242
 ia32_sys_call+0xadf/0x4310 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+0xb0/0x150 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:4953 [inline]
 slab_alloc_node mm/slub.c:5245 [inline]
 kmem_cache_alloc_node_noprof+0x989/0x16b0 mm/slub.c:5297
 kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:579
 pskb_expand_head+0x1fc/0x1610 net/core/skbuff.c:2241
 __skb_cow include/linux/skbuff.h:3853 [inline]
 skb_cow_head include/linux/skbuff.h:3887 [inline]
 erspan_xmit+0x952/0x1ce0 net/ipv4/ip_gre.c:719
 __netdev_start_xmit include/linux/netdevice.h:5248 [inline]
 netdev_start_xmit include/linux/netdevice.h:5257 [inline]
 xmit_one net/core/dev.c:3845 [inline]
 dev_hard_start_xmit+0x22f/0xa30 net/core/dev.c:3861
 sch_direct_xmit+0x3b2/0xcf0 net/sched/sch_generic.c:344
 __dev_xmit_skb net/core/dev.c:4152 [inline]
 __dev_queue_xmit+0x3588/0x5e60 net/core/dev.c:4729
 dev_queue_xmit include/linux/netdevice.h:3365 [inline]
 __bpf_tx_skb net/core/filter.c:2153 [inline]
 __bpf_redirect_common net/core/filter.c:2197 [inline]
 __bpf_redirect+0x162d/0x1760 net/core/filter.c:2204
 ____bpf_clone_redirect net/core/filter.c:2478 [inline]
 bpf_clone_redirect+0x366/0x530 net/core/filter.c:2448
 ___bpf_prog_run+0x1294/0xeba0 kernel/bpf/core.c:2000
 __bpf_prog_run32+0xc2/0xf0 kernel/bpf/core.c:2294
 bpf_dispatcher_nop_func include/linux/bpf.h:1350 [inline]
 __bpf_prog_run include/linux/filter.h:721 [inline]
 bpf_prog_run include/linux/filter.h:728 [inline]
 bpf_test_run+0x498/0xb90 net/bpf/test_run.c:434
 bpf_prog_test_run_skb+0x18c1/0x26a0 net/bpf/test_run.c:1102
 bpf_prog_test_run+0x5bf/0xa40 kernel/bpf/syscall.c:4673
 __sys_bpf+0x873/0xeb0 kernel/bpf/syscall.c:6152
 __do_sys_bpf kernel/bpf/syscall.c:6244 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:6242 [inline]
 __ia32_sys_bpf+0xa4/0xf0 kernel/bpf/syscall.c:6242
 ia32_sys_call+0xadf/0x4310 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+0xb0/0x150 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: 5992 Comm: syz.0.1 Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
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