syzbot

=====================================================
BUG: KMSAN: uninit-value in vlan_dev_hard_start_xmit+0x162/0x770 net/8021q/vlan_dev.c:113
 vlan_dev_hard_start_xmit+0x162/0x770 net/8021q/vlan_dev.c:113
 __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+0x299/0xa30 net/core/dev.c:3792
 __dev_queue_xmit+0x3cb4/0x5e20 net/core/dev.c:4629
 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+0x162d/0x1760 net/core/filter.c:2194
 ____bpf_clone_redirect net/core/filter.c:2468 [inline]
 bpf_clone_redirect+0x366/0x530 net/core/filter.c:2438
 ___bpf_prog_run+0x1294/0xeba0 kernel/bpf/core.c:2018
 __bpf_prog_run512+0xc5/0x100 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+0x547/0xd20 net/bpf/test_run.c:434
 bpf_prog_test_run_skb+0x19f8/0x26c0 net/bpf/test_run.c:1093
 bpf_prog_test_run+0x5b7/0xa30 kernel/bpf/syscall.c:4427
 __sys_bpf+0x6ca/0xe60 kernel/bpf/syscall.c:5852
 __do_sys_bpf kernel/bpf/syscall.c:5941 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5939 [inline]
 __x64_sys_bpf+0xa4/0xf0 kernel/bpf/syscall.c:5939
 x64_sys_call+0x2c3b/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:322
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x1b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

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+0x818/0xf00 mm/slub.c:4262
 kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:577
 pskb_expand_head+0x207/0x1c90 net/core/skbuff.c:2247
 skb_ensure_writable+0x4c9/0x590 net/core/skbuff.c:6241
 __bpf_try_make_writable net/core/filter.c:1673 [inline]
 bpf_try_make_writable net/core/filter.c:1679 [inline]
 bpf_try_make_head_writable net/core/filter.c:1687 [inline]
 ____bpf_clone_redirect net/core/filter.c:2462 [inline]
 bpf_clone_redirect+0x1c1/0x530 net/core/filter.c:2438
 ___bpf_prog_run+0x1294/0xeba0 kernel/bpf/core.c:2018
 __bpf_prog_run512+0xc5/0x100 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+0x547/0xd20 net/bpf/test_run.c:434
 bpf_prog_test_run_skb+0x19f8/0x26c0 net/bpf/test_run.c:1093
 bpf_prog_test_run+0x5b7/0xa30 kernel/bpf/syscall.c:4427
 __sys_bpf+0x6ca/0xe60 kernel/bpf/syscall.c:5852
 __do_sys_bpf kernel/bpf/syscall.c:5941 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5939 [inline]
 __x64_sys_bpf+0xa4/0xf0 kernel/bpf/syscall.c:5939
 x64_sys_call+0x2c3b/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:322
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd9/0x1b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 1 UID: 0 PID: 28010 Comm: syz.1.7079 Not tainted 6.15.0-rc3-syzkaller-00094-g02ddfb981de8 #0 PREEMPT(undef) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025
=====================================================