syzbot

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BUG: KMSAN: uninit-value in erspan_build_header+0x170/0x2f0 include/net/erspan.h:197
 erspan_build_header+0x170/0x2f0 include/net/erspan.h:197
 erspan_xmit+0x128a/0x1ec0 net/ipv4/ip_gre.c:706
 __netdev_start_xmit include/linux/netdevice.h:4903 [inline]
 netdev_start_xmit include/linux/netdevice.h:4917 [inline]
 xmit_one net/core/dev.c:3531 [inline]
 dev_hard_start_xmit+0x247/0xa20 net/core/dev.c:3547
 sch_direct_xmit+0x3c5/0xd50 net/sched/sch_generic.c:343
 __dev_xmit_skb net/core/dev.c:3760 [inline]
 __dev_queue_xmit+0x2e6a/0x52c0 net/core/dev.c:4301
 dev_queue_xmit include/linux/netdevice.h:3091 [inline]
 __bpf_tx_skb net/core/filter.c:2136 [inline]
 __bpf_redirect_common net/core/filter.c:2180 [inline]
 __bpf_redirect+0x14a6/0x1620 net/core/filter.c:2187
 ____bpf_clone_redirect net/core/filter.c:2460 [inline]
 bpf_clone_redirect+0x328/0x470 net/core/filter.c:2432
 ___bpf_prog_run+0x13fe/0xe0f0 kernel/bpf/core.c:1997
 __bpf_prog_run512+0xb5/0xe0 kernel/bpf/core.c:2238
 bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline]
 __bpf_prog_run include/linux/filter.h:657 [inline]
 bpf_prog_run include/linux/filter.h:664 [inline]
 bpf_test_run+0x499/0xc30 net/bpf/test_run.c:425
 bpf_prog_test_run_skb+0x14ea/0x1f20 net/bpf/test_run.c:1058
 bpf_prog_test_run+0x6b7/0xad0 kernel/bpf/syscall.c:4240
 __sys_bpf+0x6aa/0xd90 kernel/bpf/syscall.c:5649
 __do_sys_bpf kernel/bpf/syscall.c:5738 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5736 [inline]
 __x64_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5736
 do_syscall_64+0xd5/0x1f0
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:3804 [inline]
 slab_alloc_node mm/slub.c:3845 [inline]
 kmem_cache_alloc_node+0x613/0xc50 mm/slub.c:3888
 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:577
 pskb_expand_head+0x222/0x19d0 net/core/skbuff.c:2245
 __skb_cow include/linux/skbuff.h:3671 [inline]
 skb_cow_head include/linux/skbuff.h:3705 [inline]
 erspan_xmit+0xb08/0x1ec0 net/ipv4/ip_gre.c:692
 __netdev_start_xmit include/linux/netdevice.h:4903 [inline]
 netdev_start_xmit include/linux/netdevice.h:4917 [inline]
 xmit_one net/core/dev.c:3531 [inline]
 dev_hard_start_xmit+0x247/0xa20 net/core/dev.c:3547
 sch_direct_xmit+0x3c5/0xd50 net/sched/sch_generic.c:343
 __dev_xmit_skb net/core/dev.c:3760 [inline]
 __dev_queue_xmit+0x2e6a/0x52c0 net/core/dev.c:4301
 dev_queue_xmit include/linux/netdevice.h:3091 [inline]
 __bpf_tx_skb net/core/filter.c:2136 [inline]
 __bpf_redirect_common net/core/filter.c:2180 [inline]
 __bpf_redirect+0x14a6/0x1620 net/core/filter.c:2187
 ____bpf_clone_redirect net/core/filter.c:2460 [inline]
 bpf_clone_redirect+0x328/0x470 net/core/filter.c:2432
 ___bpf_prog_run+0x13fe/0xe0f0 kernel/bpf/core.c:1997
 __bpf_prog_run512+0xb5/0xe0 kernel/bpf/core.c:2238
 bpf_dispatcher_nop_func include/linux/bpf.h:1234 [inline]
 __bpf_prog_run include/linux/filter.h:657 [inline]
 bpf_prog_run include/linux/filter.h:664 [inline]
 bpf_test_run+0x499/0xc30 net/bpf/test_run.c:425
 bpf_prog_test_run_skb+0x14ea/0x1f20 net/bpf/test_run.c:1058
 bpf_prog_test_run+0x6b7/0xad0 kernel/bpf/syscall.c:4240
 __sys_bpf+0x6aa/0xd90 kernel/bpf/syscall.c:5649
 __do_sys_bpf kernel/bpf/syscall.c:5738 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5736 [inline]
 __x64_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5736
 do_syscall_64+0xd5/0x1f0
 entry_SYSCALL_64_after_hwframe+0x6d/0x75

CPU: 0 PID: 5041 Comm: syz-executor167 Not tainted 6.8.0-syzkaller-11743-ga4145ce1e7bc #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
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