=====================================================
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/0x33f0 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/0x33f0 lib/iov_iter.c:185
 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:4132 [inline]
 netlink_recvmsg+0x4bb/0xfe0 net/netlink/af_netlink.c:1940
 sock_recvmsg_nosec net/socket.c:1017 [inline]
 sock_recvmsg+0x2df/0x390 net/socket.c:1039
 __sys_recvfrom+0x282/0x550 net/socket.c:2230
 __do_sys_recvfrom net/socket.c:2245 [inline]
 __se_sys_recvfrom net/socket.c:2241 [inline]
 __x64_sys_recvfrom+0x130/0x200 net/socket.c:2241
 x64_sys_call+0x1f98/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:46
 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:
 pskb_expand_head+0x310/0x1610 net/core/skbuff.c:2249
 netlink_trim+0x496/0x500 net/netlink/af_netlink.c:1295
 netlink_unicast+0x9a/0x1290 net/netlink/af_netlink.c:1329
 nlmsg_unicast include/net/netlink.h:1184 [inline]
 rtnl_unicast+0x62/0x90 net/core/rtnetlink.c:949
 tc_chain_notify+0x36e/0x610 net/sched/cls_api.c:3022
 tc_ctl_chain+0x1b8c/0x26e0 net/sched/cls_api.c:3211
 rtnetlink_rcv_msg+0x113d/0x14b0 net/core/rtnetlink.c:6953
 netlink_rcv_skb+0x54d/0x680 net/netlink/af_netlink.c:2534
 rtnetlink_rcv+0x35/0x40 net/core/rtnetlink.c:6971
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0xed8/0x1290 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x10b3/0x1250 net/netlink/af_netlink.c:1883
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x330/0x3d0 net/socket.c:727
 ____sys_sendmsg+0x7e0/0xd80 net/socket.c:2566
 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2620
 __sys_sendmsg net/socket.c:2652 [inline]
 __do_sys_sendmsg net/socket.c:2657 [inline]
 __se_sys_sendmsg net/socket.c:2655 [inline]
 __x64_sys_sendmsg+0x211/0x3e0 net/socket.c:2655
 x64_sys_call+0x32fb/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:47
 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]
 __do_kmalloc_node mm/slub.c:4327 [inline]
 __kmalloc_node_track_caller_noprof+0x96d/0x12f0 mm/slub.c:4347
 kmalloc_reserve+0x22f/0x4b0 net/core/skbuff.c:601
 __alloc_skb+0x347/0x7d0 net/core/skbuff.c:670
 alloc_skb include/linux/skbuff.h:1336 [inline]
 tc_chain_notify+0x1b4/0x610 net/sched/cls_api.c:3010
 tc_ctl_chain+0x1b8c/0x26e0 net/sched/cls_api.c:3211
 rtnetlink_rcv_msg+0x113d/0x14b0 net/core/rtnetlink.c:6953
 netlink_rcv_skb+0x54d/0x680 net/netlink/af_netlink.c:2534
 rtnetlink_rcv+0x35/0x40 net/core/rtnetlink.c:6971
 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline]
 netlink_unicast+0xed8/0x1290 net/netlink/af_netlink.c:1339
 netlink_sendmsg+0x10b3/0x1250 net/netlink/af_netlink.c:1883
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x330/0x3d0 net/socket.c:727
 ____sys_sendmsg+0x7e0/0xd80 net/socket.c:2566
 ___sys_sendmsg+0x271/0x3b0 net/socket.c:2620
 __sys_sendmsg net/socket.c:2652 [inline]
 __do_sys_sendmsg net/socket.c:2657 [inline]
 __se_sys_sendmsg net/socket.c:2655 [inline]
 __x64_sys_sendmsg+0x211/0x3e0 net/socket.c:2655
 x64_sys_call+0x32fb/0x3db0 arch/x86/include/generated/asm/syscalls_64.h:47
 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 32-35 of 44 are uninitialized
Memory access of size 44 starts at ffff888059095b80
Data copied to user address 00007fe0604c7010

CPU: 1 UID: 0 PID: 6483 Comm: syz.1.148 Not tainted 6.16.0-rc2-syzkaller-00231-g75f5f23f8787 #0 PREEMPT(undef) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
=====================================================