=====================================================
BUG: KMSAN: uninit-value in eth_type_trans+0x69d/0x9a0 net/ethernet/eth.c:176
 eth_type_trans+0x69d/0x9a0 net/ethernet/eth.c:176
 loopback_xmit+0x4fd/0x750 drivers/net/loopback.c:87
 __netdev_start_xmit include/linux/netdevice.h:5215 [inline]
 netdev_start_xmit include/linux/netdevice.h:5224 [inline]
 xmit_one net/core/dev.c:3830 [inline]
 dev_hard_start_xmit+0x22f/0xa30 net/core/dev.c:3846
 __dev_queue_xmit+0x3cb4/0x5e20 net/core/dev.c:4713
 dev_queue_xmit include/linux/netdevice.h:3355 [inline]
 __bpf_tx_skb net/core/filter.c:2144 [inline]
 __bpf_redirect_common net/core/filter.c:2188 [inline]
 __bpf_redirect+0x162d/0x1760 net/core/filter.c:2195
 ____bpf_clone_redirect net/core/filter.c:2469 [inline]
 bpf_clone_redirect+0x366/0x530 net/core/filter.c:2439
 ___bpf_prog_run+0x1297/0xeba0 kernel/bpf/core.c:2018
 __bpf_prog_run512+0xc5/0x100 kernel/bpf/core.c:2313
 bpf_dispatcher_nop_func include/linux/bpf.h:1322 [inline]
 __bpf_prog_run include/linux/filter.h:718 [inline]
 bpf_prog_run include/linux/filter.h:725 [inline]
 bpf_test_run+0x54a/0xd20 net/bpf/test_run.c:434
 bpf_prog_test_run_skb+0x19f8/0x26c0 net/bpf/test_run.c:1099
 bpf_prog_test_run+0x5c2/0xa40 kernel/bpf/syscall.c:4429
 __sys_bpf+0x6ca/0xe60 kernel/bpf/syscall.c:5854
 __do_sys_bpf kernel/bpf/syscall.c:5943 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5941 [inline]
 __x64_sys_bpf+0xa4/0xf0 kernel/bpf/syscall.c:5941
 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+0xd9/0x210 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:4154 [inline]
 slab_alloc_node mm/slub.c:4197 [inline]
 kmem_cache_alloc_node_noprof+0x818/0xf00 mm/slub.c:4249
 kmalloc_reserve+0x13c/0x4b0 net/core/skbuff.c:579
 pskb_expand_head+0x1fc/0x1610 net/core/skbuff.c:2241
 skb_ensure_writable+0x44e/0x510 net/core/skbuff.c:6267
 __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:2463 [inline]
 bpf_clone_redirect+0x1c1/0x530 net/core/filter.c:2439
 ___bpf_prog_run+0x1297/0xeba0 kernel/bpf/core.c:2018
 __bpf_prog_run512+0xc5/0x100 kernel/bpf/core.c:2313
 bpf_dispatcher_nop_func include/linux/bpf.h:1322 [inline]
 __bpf_prog_run include/linux/filter.h:718 [inline]
 bpf_prog_run include/linux/filter.h:725 [inline]
 bpf_test_run+0x54a/0xd20 net/bpf/test_run.c:434
 bpf_prog_test_run_skb+0x19f8/0x26c0 net/bpf/test_run.c:1099
 bpf_prog_test_run+0x5c2/0xa40 kernel/bpf/syscall.c:4429
 __sys_bpf+0x6ca/0xe60 kernel/bpf/syscall.c:5854
 __do_sys_bpf kernel/bpf/syscall.c:5943 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5941 [inline]
 __x64_sys_bpf+0xa4/0xf0 kernel/bpf/syscall.c:5941
 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+0xd9/0x210 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 1 UID: 0 PID: 19024 Comm: syz.8.4264 Not tainted 6.16.0-rc3-syzkaller-00044-g7595b66ae9de #0 PREEMPT(undef) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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