=====================================================
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:302 [inline]
BUG: KMSAN: kernel-infoleak in iterate_and_advance include/linux/iov_iter.h:330 [inline]
BUG: KMSAN: kernel-infoleak in _copy_to_iter+0xef3/0x33f0 lib/iov_iter.c:197
 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:302 [inline]
 iterate_and_advance include/linux/iov_iter.h:330 [inline]
 _copy_to_iter+0xef3/0x33f0 lib/iov_iter.c:197
 copy_to_iter include/linux/uio.h:220 [inline]
 simple_copy_to_iter net/core/datagram.c:521 [inline]
 __skb_datagram_iter+0x196/0x12c0 net/core/datagram.c:402
 skb_copy_datagram_iter+0x5b/0x1e0 net/core/datagram.c:535
 skb_copy_datagram_msg include/linux/skbuff.h:4217 [inline]
 packet_recvmsg+0xe2b/0x24e0 net/packet/af_packet.c:3472
 sock_recvmsg_nosec net/socket.c:1078 [inline]
 sock_recvmsg+0x2df/0x390 net/socket.c:1100
 sock_read_iter+0x2c8/0x360 net/socket.c:1170
 new_sync_read fs/read_write.c:491 [inline]
 vfs_read+0x8ed/0xf90 fs/read_write.c:572
 ksys_read fs/read_write.c:715 [inline]
 __do_sys_read fs/read_write.c:724 [inline]
 __se_sys_read fs/read_write.c:722 [inline]
 __x64_sys_read+0x1fb/0x4d0 fs/read_write.c:722
 x64_sys_call+0x3123/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:1
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd3/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
 pskb_expand_head+0x310/0x15d0 net/core/skbuff.c:2290
 netlink_trim+0x3a3/0x450 net/netlink/af_netlink.c:1299
 netlink_broadcast_filtered+0x80/0x28f0 net/netlink/af_netlink.c:1512
 nlmsg_multicast_filtered include/net/netlink.h:1165 [inline]
 nlmsg_multicast include/net/netlink.h:1184 [inline]
 nlmsg_notify+0x15b/0x2f0 net/netlink/af_netlink.c:2593
 rtnetlink_send+0x73/0xa0 net/core/rtnetlink.c:942
 tc_chain_notify+0x3e2/0x610 net/sched/cls_api.c:3024
 __tcf_chain_get+0x53f/0x840 net/sched/cls_api.c:656
 tcf_chain_get net/sched/cls_api.c:669 [inline]
 tc_new_tfilter+0xeaa/0x2d20 net/sched/cls_api.c:2329
 rtnetlink_rcv_msg+0x106f/0x14b0 net/core/rtnetlink.c:6958
 netlink_rcv_skb+0x54d/0x680 net/netlink/af_netlink.c:2550
 rtnetlink_rcv+0x35/0x40 net/core/rtnetlink.c:6985
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0xf04/0x12b0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x10b3/0x1250 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x333/0x3d0 net/socket.c:742
 ____sys_sendmsg+0x7f5/0xcf0 net/socket.c:2592
 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2646
 __sys_sendmsg net/socket.c:2678 [inline]
 __do_sys_sendmsg net/socket.c:2683 [inline]
 __se_sys_sendmsg net/socket.c:2681 [inline]
 __x64_sys_sendmsg+0x211/0x3e0 net/socket.c:2681
 x64_sys_call+0x1c60/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd3/0xf80 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:4960 [inline]
 slab_alloc_node mm/slub.c:5263 [inline]
 __do_kmalloc_node mm/slub.c:5656 [inline]
 __kmalloc_node_track_caller_noprof+0xb77/0x1c90 mm/slub.c:5764
 kmalloc_reserve+0x22f/0x4b0 net/core/skbuff.c:608
 __alloc_skb+0x805/0x1040 net/core/skbuff.c:690
 alloc_skb include/linux/skbuff.h:1383 [inline]
 tc_chain_notify+0x1b4/0x610 net/sched/cls_api.c:3010
 __tcf_chain_get+0x53f/0x840 net/sched/cls_api.c:656
 tcf_chain_get net/sched/cls_api.c:669 [inline]
 tc_new_tfilter+0xeaa/0x2d20 net/sched/cls_api.c:2329
 rtnetlink_rcv_msg+0x106f/0x14b0 net/core/rtnetlink.c:6958
 netlink_rcv_skb+0x54d/0x680 net/netlink/af_netlink.c:2550
 rtnetlink_rcv+0x35/0x40 net/core/rtnetlink.c:6985
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0xf04/0x12b0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x10b3/0x1250 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x333/0x3d0 net/socket.c:742
 ____sys_sendmsg+0x7f5/0xcf0 net/socket.c:2592
 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2646
 __sys_sendmsg net/socket.c:2678 [inline]
 __do_sys_sendmsg net/socket.c:2683 [inline]
 __se_sys_sendmsg net/socket.c:2681 [inline]
 __x64_sys_sendmsg+0x211/0x3e0 net/socket.c:2681
 x64_sys_call+0x1c60/0x3e70 arch/x86/include/generated/asm/syscalls_64.h:47
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd3/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Bytes 32-35 of 44 are uninitialized
Memory access of size 44 starts at ffff8880880418c0
Data copied to user address 0000200000000000

CPU: 0 UID: 0 PID: 7475 Comm: syz.7.288 Not tainted syzkaller #0 PREEMPT(none) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
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