=====================================================
BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:114 [inline]
BUG: KMSAN: kernel-infoleak in _inline_copy_to_user include/linux/uaccess.h:196 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_user+0xcc/0x120 lib/usercopy.c:26
 instrument_copy_to_user include/linux/instrumented.h:114 [inline]
 _inline_copy_to_user include/linux/uaccess.h:196 [inline]
 _copy_to_user+0xcc/0x120 lib/usercopy.c:26
 copy_to_user include/linux/uaccess.h:225 [inline]
 move_addr_to_user+0x29a/0x400 net/socket.c:306
 ____sys_recvmsg+0x232/0x610 net/socket.c:2857
 ___sys_recvmsg+0x20b/0x850 net/socket.c:2892
 do_recvmmsg+0x40e/0xdf0 net/socket.c:2987
 __sys_recvmmsg net/socket.c:3061 [inline]
 __do_sys_recvmmsg net/socket.c:3084 [inline]
 __se_sys_recvmmsg net/socket.c:3077 [inline]
 __x64_sys_recvmmsg+0x383/0x500 net/socket.c:3077
 x64_sys_call+0x2f74/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:300
 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 stored to memory at:
 packet_recvmsg+0x1595/0x24e0 net/packet/af_packet.c:3516
 sock_recvmsg_nosec+0x240/0x2f0 net/socket.c:1078
 ____sys_recvmsg+0x4e5/0x610 net/socket.c:2848
 ___sys_recvmsg+0x20b/0x850 net/socket.c:2892
 do_recvmmsg+0x40e/0xdf0 net/socket.c:2987
 __sys_recvmmsg net/socket.c:3061 [inline]
 __do_sys_recvmmsg net/socket.c:3084 [inline]
 __se_sys_recvmmsg net/socket.c:3077 [inline]
 __x64_sys_recvmmsg+0x383/0x500 net/socket.c:3077
 x64_sys_call+0x2f74/0x3e30 arch/x86/include/generated/asm/syscalls_64.h:300
 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 stored to memory at:
 eth_header_parse+0xdb/0x160 net/ethernet/eth.c:204
 dev_parse_header include/linux/netdevice.h:3429 [inline]
 packet_rcv+0x108f/0x23a0 net/packet/af_packet.c:2186
 dev_queue_xmit_nit+0x13f2/0x15a0 net/core/dev.c:2586
 xmit_one net/core/dev.c:3841 [inline]
 dev_hard_start_xmit+0x16b/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_run512+0xc5/0x100 kernel/bpf/core.c:2296
 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]
 __x64_sys_bpf+0xa4/0xf0 kernel/bpf/syscall.c:6242
 x64_sys_call+0x3550/0x3e30 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: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_ensure_writable+0x44e/0x510 net/core/skbuff.c:6273
 __bpf_try_make_writable net/core/filter.c:1682 [inline]
 bpf_try_make_writable net/core/filter.c:1688 [inline]
 bpf_try_make_head_writable net/core/filter.c:1696 [inline]
 ____bpf_clone_redirect net/core/filter.c:2472 [inline]
 bpf_clone_redirect+0x1c1/0x530 net/core/filter.c:2448
 ___bpf_prog_run+0x1294/0xeba0 kernel/bpf/core.c:2000
 __bpf_prog_run512+0xc5/0x100 kernel/bpf/core.c:2296
 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]
 __x64_sys_bpf+0xa4/0xf0 kernel/bpf/syscall.c:6242
 x64_sys_call+0x3550/0x3e30 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

Bytes 12-17 of 20 are uninitialized
Memory access of size 20 starts at ffff88804be3ba38
Data copied to user address 0000000020000ac0

CPU: 1 UID: 0 PID: 6580 Comm: syz.2.17 Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
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