===================================================== BUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:114 [inline] BUG: KMSAN: kernel-infoleak in copy_to_user_iter lib/iov_iter.c:24 [inline] BUG: KMSAN: kernel-infoleak in iterate_ubuf include/linux/iov_iter.h:30 [inline] BUG: KMSAN: kernel-infoleak in iterate_and_advance2 include/linux/iov_iter.h:300 [inline] BUG: KMSAN: kernel-infoleak in iterate_and_advance include/linux/iov_iter.h:328 [inline] BUG: KMSAN: kernel-infoleak in _copy_to_iter+0xf0e/0x32f0 lib/iov_iter.c:185 instrument_copy_to_user include/linux/instrumented.h:114 [inline] copy_to_user_iter lib/iov_iter.c:24 [inline] iterate_ubuf include/linux/iov_iter.h:30 [inline] iterate_and_advance2 include/linux/iov_iter.h:300 [inline] iterate_and_advance include/linux/iov_iter.h:328 [inline] _copy_to_iter+0xf0e/0x32f0 lib/iov_iter.c:185 copy_to_iter include/linux/uio.h:220 [inline] simple_copy_to_iter net/core/datagram.c:524 [inline] __skb_datagram_iter+0x18f/0x1250 net/core/datagram.c:401 skb_copy_datagram_iter+0x5b/0x1e0 net/core/datagram.c:538 tun_put_user drivers/net/tun.c:2082 [inline] tun_do_read+0x26d8/0x30f0 drivers/net/tun.c:2161 tun_chr_read_iter+0x393/0x6b0 drivers/net/tun.c:2185 new_sync_read fs/read_write.c:489 [inline] vfs_read+0x845/0xef0 fs/read_write.c:570 ksys_read fs/read_write.c:713 [inline] __do_sys_read fs/read_write.c:722 [inline] __se_sys_read fs/read_write.c:720 [inline] __x64_sys_read+0x1fb/0x4d0 fs/read_write.c:720 x64_sys_call+0x39db/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:1 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: pskb_expand_head+0x313/0x1c90 net/core/skbuff.c:2255 __skb_cow include/linux/skbuff.h:3772 [inline] skb_cow_head include/linux/skbuff.h:3806 [inline] erspan_xmit+0x952/0x1ce0 net/ipv4/ip_gre.c:719 __netdev_start_xmit include/linux/netdevice.h:5203 [inline] netdev_start_xmit include/linux/netdevice.h:5212 [inline] xmit_one net/core/dev.c:3776 [inline] dev_hard_start_xmit+0x299/0xa30 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] neigh_resolve_output+0x9c5/0xaf0 net/core/neighbour.c:1512 neigh_output include/net/neighbour.h:539 [inline] ip_finish_output2+0x1abc/0x1d50 net/ipv4/ip_output.c:235 ip_do_fragment+0x115f/0x27e0 net/ipv4/ip_output.c:908 ip_fragment+0x1ad/0x2c0 net/ipv4/ip_output.c:-1 __ip_finish_output+0x5d8/0x860 net/ipv4/ip_output.c:311 ip_finish_output+0x4a/0x640 net/ipv4/ip_output.c:323 NF_HOOK_COND include/linux/netfilter.h:303 [inline] ip_output+0x149/0x3d0 net/ipv4/ip_output.c:433 dst_output include/net/dst.h:459 [inline] ip_local_out+0x1b2/0x210 net/ipv4/ip_output.c:129 iptunnel_xmit+0x67a/0xc00 net/ipv4/ip_tunnel_core.c:82 ip_tunnel_xmit+0x3973/0x3be0 net/ipv4/ip_tunnel.c:859 __gre_xmit net/ipv4/ip_gre.c:488 [inline] ipgre_xmit+0x1098/0x1250 net/ipv4/ip_gre.c:692 __netdev_start_xmit include/linux/netdevice.h:5203 [inline] netdev_start_xmit include/linux/netdevice.h:5212 [inline] xmit_one net/core/dev.c:3776 [inline] dev_hard_start_xmit+0x299/0xa30 net/core/dev.c:3792 __dev_queue_xmit+0x3cb4/0x5e20 net/core/dev.c:4629 dev_queue_xmit include/linux/netdevice.h:3350 [inline] __bpf_tx_skb net/core/filter.c:2143 [inline] __bpf_redirect_no_mac net/core/filter.c:2173 [inline] __bpf_redirect+0xda6/0x1760 net/core/filter.c:2196 ____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+0x547/0xd20 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:4167 [inline] slab_alloc_node mm/slub.c:4210 [inline] __do_kmalloc_node mm/slub.c:4340 [inline] __kmalloc_node_track_caller_noprof+0x96d/0x12f0 mm/slub.c:4360 kmalloc_reserve+0x22f/0x4b0 net/core/skbuff.c:599 __alloc_skb+0x347/0x7d0 net/core/skbuff.c:668 alloc_skb include/linux/skbuff.h:1340 [inline] ip_frag_next+0x17a/0xe80 net/ipv4/ip_output.c:687 ip_do_fragment+0xf73/0x27e0 net/ipv4/ip_output.c:897 ip_fragment+0x1ad/0x2c0 net/ipv4/ip_output.c:-1 __ip_finish_output+0x5d8/0x860 net/ipv4/ip_output.c:311 ip_finish_output+0x4a/0x640 net/ipv4/ip_output.c:323 NF_HOOK_COND include/linux/netfilter.h:303 [inline] ip_output+0x149/0x3d0 net/ipv4/ip_output.c:433 dst_output include/net/dst.h:459 [inline] ip_local_out+0x1b2/0x210 net/ipv4/ip_output.c:129 iptunnel_xmit+0x67a/0xc00 net/ipv4/ip_tunnel_core.c:82 ip_tunnel_xmit+0x3973/0x3be0 net/ipv4/ip_tunnel.c:859 __gre_xmit net/ipv4/ip_gre.c:488 [inline] ipgre_xmit+0x1098/0x1250 net/ipv4/ip_gre.c:692 __netdev_start_xmit include/linux/netdevice.h:5203 [inline] netdev_start_xmit include/linux/netdevice.h:5212 [inline] xmit_one net/core/dev.c:3776 [inline] dev_hard_start_xmit+0x299/0xa30 net/core/dev.c:3792 __dev_queue_xmit+0x3cb4/0x5e20 net/core/dev.c:4629 dev_queue_xmit include/linux/netdevice.h:3350 [inline] __bpf_tx_skb net/core/filter.c:2143 [inline] __bpf_redirect_no_mac net/core/filter.c:2173 [inline] __bpf_redirect+0xda6/0x1760 net/core/filter.c:2196 ____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+0x547/0xd20 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 38-41 of 1000 are uninitialized Memory access of size 1000 starts at ffff88804c289880 Data copied to user address 00007ffe172fa290 CPU: 0 UID: 0 PID: 8970 Comm: syz-executor Not tainted 6.15.0-rc3-syzkaller-00094-g02ddfb981de8 #0 PREEMPT(undef) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 =====================================================