===================================================== 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 __sys_recvmsg net/socket.c:2861 [inline] __do_sys_recvmsg net/socket.c:2867 [inline] __se_sys_recvmsg net/socket.c:2864 [inline] __x64_sys_recvmsg+0x20e/0x3d0 net/socket.c:2864 x64_sys_call+0x11ff/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:48 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:3571 sock_recvmsg_nosec net/socket.c:1017 [inline] sock_recvmsg+0x2df/0x390 net/socket.c:1039 ____sys_recvmsg+0x193/0x610 net/socket.c:2786 ___sys_recvmsg+0x20b/0x850 net/socket.c:2828 __sys_recvmsg net/socket.c:2861 [inline] __do_sys_recvmsg net/socket.c:2867 [inline] __se_sys_recvmsg net/socket.c:2864 [inline] __x64_sys_recvmsg+0x20e/0x3d0 net/socket.c:2864 x64_sys_call+0x11ff/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:48 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:3417 [inline] packet_rcv+0xeea/0x20b0 net/packet/af_packet.c:2240 dev_queue_xmit_nit+0x13f2/0x15a0 net/core/dev.c:2587 xmit_one net/core/dev.c:3826 [inline] dev_hard_start_xmit+0x16b/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+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:1322 [inline] __bpf_prog_run include/linux/filter.h:709 [inline] bpf_prog_run include/linux/filter.h:725 [inline] bpf_test_run+0x8e8/0xd20 net/bpf/test_run.c:434 bpf_prog_test_run_skb+0x19f8/0x26c0 net/bpf/test_run.c:1099 bpf_prog_test_run+0x5bf/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+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:1322 [inline] __bpf_prog_run include/linux/filter.h:709 [inline] bpf_prog_run include/linux/filter.h:725 [inline] bpf_test_run+0x8e8/0xd20 net/bpf/test_run.c:434 bpf_prog_test_run_skb+0x19f8/0x26c0 net/bpf/test_run.c:1099 bpf_prog_test_run+0x5bf/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 Bytes 12-17 of 20 are uninitialized Memory access of size 20 starts at ffff888058503b58 Data copied to user address 0000200000000500 CPU: 1 UID: 0 PID: 6375 Comm: syz.3.138 Not tainted 6.16.0-rc3-syzkaller-00233-g35e261cd95dd #0 PREEMPT(undef) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 =====================================================