=====================================================
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+0xc8/0x120 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+0xc8/0x120 lib/usercopy.c:26
 copy_to_user include/linux/uaccess.h:225 [inline]
 move_addr_to_user+0x28b/0x400 net/socket.c:293
 ____sys_recvmsg+0x232/0x620 net/socket.c:2800
 ___sys_recvmsg+0x223/0x840 net/socket.c:2835
 do_recvmmsg+0x45a/0xfc0 net/socket.c:2930
 __sys_recvmmsg net/socket.c:3004 [inline]
 __do_sys_recvmmsg net/socket.c:3027 [inline]
 __se_sys_recvmmsg net/socket.c:3020 [inline]
 __x64_sys_recvmmsg+0x397/0x490 net/socket.c:3020
 x64_sys_call+0x35ba/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:300
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
 packet_recvmsg+0x17c7/0x25b0 net/packet/af_packet.c:3572
 sock_recvmsg_nosec+0x22f/0x2b0 net/socket.c:1023
 ____sys_recvmsg+0x541/0x620 net/socket.c:2791
 ___sys_recvmsg+0x223/0x840 net/socket.c:2835
 do_recvmmsg+0x45a/0xfc0 net/socket.c:2930
 __sys_recvmmsg net/socket.c:3004 [inline]
 __do_sys_recvmmsg net/socket.c:3027 [inline]
 __se_sys_recvmmsg net/socket.c:3020 [inline]
 __x64_sys_recvmmsg+0x397/0x490 net/socket.c:3020
 x64_sys_call+0x35ba/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:300
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
 eth_header_parse+0xe5/0x160 net/ethernet/eth.c:204
 dev_parse_header include/linux/netdevice.h:3375 [inline]
 packet_rcv+0xefc/0x2050 net/packet/af_packet.c:2240
 dev_queue_xmit_nit+0x130a/0x1460 net/core/dev.c:2563
 xmit_one net/core/dev.c:3802 [inline]
 dev_hard_start_xmit+0x17d/0xa20 net/core/dev.c:3822
 sch_direct_xmit+0x399/0xd40 net/sched/sch_generic.c:343
 __dev_xmit_skb net/core/dev.c:4045 [inline]
 __dev_queue_xmit+0x30b9/0x57d0 net/core/dev.c:4621
 dev_queue_xmit include/linux/netdevice.h:3313 [inline]
 __bpf_tx_skb net/core/filter.c:2135 [inline]
 __bpf_redirect_common net/core/filter.c:2179 [inline]
 __bpf_redirect+0x1511/0x1690 net/core/filter.c:2186
 ____bpf_clone_redirect net/core/filter.c:2460 [inline]
 bpf_clone_redirect+0x37e/0x500 net/core/filter.c:2430
 ___bpf_prog_run+0x13fe/0xe0f0 kernel/bpf/core.c:2015
 __bpf_prog_run512+0xc5/0xf0 kernel/bpf/core.c:2258
 bpf_dispatcher_nop_func include/linux/bpf.h:1290 [inline]
 __bpf_prog_run include/linux/filter.h:701 [inline]
 bpf_prog_run include/linux/filter.h:708 [inline]
 bpf_test_run+0x546/0xd20 net/bpf/test_run.c:434
 bpf_prog_test_run_skb+0x18fa/0x25a0 net/bpf/test_run.c:1093
 bpf_prog_test_run+0x5e5/0xa30 kernel/bpf/syscall.c:4407
 __sys_bpf+0x6aa/0xd90 kernel/bpf/syscall.c:5813
 __do_sys_bpf kernel/bpf/syscall.c:5902 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5900 [inline]
 __x64_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5900
 x64_sys_call+0x329c/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:322
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:4121 [inline]
 slab_alloc_node mm/slub.c:4164 [inline]
 kmem_cache_alloc_node_noprof+0x907/0xe00 mm/slub.c:4216
 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:515
 pskb_expand_head+0x21f/0x1b70 net/core/skbuff.c:2185
 skb_ensure_writable+0x496/0x520 net/core/skbuff.c:6124
 __bpf_try_make_writable net/core/filter.c:1665 [inline]
 bpf_try_make_writable net/core/filter.c:1671 [inline]
 bpf_try_make_head_writable net/core/filter.c:1679 [inline]
 ____bpf_clone_redirect net/core/filter.c:2454 [inline]
 bpf_clone_redirect+0x1c5/0x500 net/core/filter.c:2430
 ___bpf_prog_run+0x13fe/0xe0f0 kernel/bpf/core.c:2015
 __bpf_prog_run512+0xc5/0xf0 kernel/bpf/core.c:2258
 bpf_dispatcher_nop_func include/linux/bpf.h:1290 [inline]
 __bpf_prog_run include/linux/filter.h:701 [inline]
 bpf_prog_run include/linux/filter.h:708 [inline]
 bpf_test_run+0x546/0xd20 net/bpf/test_run.c:434
 bpf_prog_test_run_skb+0x18fa/0x25a0 net/bpf/test_run.c:1093
 bpf_prog_test_run+0x5e5/0xa30 kernel/bpf/syscall.c:4407
 __sys_bpf+0x6aa/0xd90 kernel/bpf/syscall.c:5813
 __do_sys_bpf kernel/bpf/syscall.c:5902 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5900 [inline]
 __x64_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5900
 x64_sys_call+0x329c/0x3c30 arch/x86/include/generated/asm/syscalls_64.h:322
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x1e0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Bytes 12-17 of 20 are uninitialized
Memory access of size 20 starts at ffff88804f5e7a38
Data copied to user address 0000000020000ac0

CPU: 0 UID: 0 PID: 6931 Comm: syz.0.15 Not tainted 6.14.0-rc4-syzkaller-gd082ecbc71e9 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
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