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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+0x29c/0x410 net/socket.c:293
 ____sys_recvmsg+0x232/0x610 net/socket.c:2793
 ___sys_recvmsg+0x20b/0x850 net/socket.c:2828
 do_recvmmsg+0x40e/0xdf0 net/socket.c:2923
 __sys_recvmmsg net/socket.c:2997 [inline]
 __do_sys_recvmmsg net/socket.c:3020 [inline]
 __se_sys_recvmmsg net/socket.c:3013 [inline]
 __x64_sys_recvmmsg+0x383/0x500 net/socket.c:3013
 x64_sys_call+0x220d/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:300
 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 stored to memory at:
 packet_recvmsg+0x1595/0x24e0 net/packet/af_packet.c:3571
 sock_recvmsg_nosec+0x23d/0x2f0 net/socket.c:1017
 ____sys_recvmsg+0x4e5/0x610 net/socket.c:2784
 ___sys_recvmsg+0x20b/0x850 net/socket.c:2828
 do_recvmmsg+0x40e/0xdf0 net/socket.c:2923
 __sys_recvmmsg net/socket.c:2997 [inline]
 __do_sys_recvmmsg net/socket.c:3020 [inline]
 __se_sys_recvmmsg net/socket.c:3013 [inline]
 __x64_sys_recvmmsg+0x383/0x500 net/socket.c:3013
 x64_sys_call+0x220d/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:300
 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 stored to memory at:
 eth_header_parse+0xdb/0x160 net/ethernet/eth.c:204
 dev_parse_header include/linux/netdevice.h:3412 [inline]
 packet_rcv+0xeed/0x20b0 net/packet/af_packet.c:2240
 dev_queue_xmit_nit+0x13f5/0x15a0 net/core/dev.c:2533
 xmit_one net/core/dev.c:3772 [inline]
 dev_hard_start_xmit+0x1ce/0xa30 net/core/dev.c:3792
 sch_direct_xmit+0x3b2/0xcf0 net/sched/sch_generic.c:343
 __dev_xmit_skb net/core/dev.c:4018 [inline]
 __dev_queue_xmit+0x35e6/0x5e20 net/core/dev.c:4595
 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+0x54a/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:4153 [inline]
 slab_alloc_node mm/slub.c:4196 [inline]
 kmem_cache_alloc_node_noprof+0x818/0xf00 mm/slub.c:4248
 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+0x54a/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

Bytes 12-17 of 20 are uninitialized
Memory access of size 20 starts at ffff88804ffd3a38
Data copied to user address 0000000020000ac0

CPU: 0 UID: 0 PID: 6875 Comm: syz.3.18 Not tainted 6.15.0-rc6-syzkaller-gfee3e843b309 #0 PREEMPT(undef) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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