=====================================================
BUG: KMSAN: uninit-value in hex_string+0x6b1/0x7b0 lib/vsprintf.c:1177
 hex_string+0x6b1/0x7b0 lib/vsprintf.c:1177
 pointer+0x2d1/0x1ac0 lib/vsprintf.c:2421
 vsnprintf+0x1648/0x29e0 lib/vsprintf.c:2822
 seq_vprintf fs/seq_file.c:391 [inline]
 seq_printf+0x261/0x390 fs/seq_file.c:406
 dev_mc_seq_show+0x238/0x3b0 net/core/net-procfs.c:375
 seq_read_iter+0x1445/0x20c0 fs/seq_file.c:272
 seq_read+0x1c9/0x290 fs/seq_file.c:162
 pde_read fs/proc/inode.c:316 [inline]
 proc_reg_read+0x264/0x4a0 fs/proc/inode.c:328
 vfs_read+0x370/0xf50 fs/read_write.c:468
 ksys_read+0x20f/0x4c0 fs/read_write.c:613
 __do_sys_read fs/read_write.c:623 [inline]
 __se_sys_read fs/read_write.c:621 [inline]
 __x64_sys_read+0x93/0xd0 fs/read_write.c:621
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Uninit was created at:
 slab_post_alloc_hook+0x12f/0xb70 mm/slab.h:767
 slab_alloc_node mm/slub.c:3478 [inline]
 __kmem_cache_alloc_node+0x536/0x8d0 mm/slub.c:3517
 kmalloc_trace+0x51/0x200 mm/slab_common.c:1114
 kmalloc include/linux/slab.h:599 [inline]
 __hw_addr_create net/core/dev_addr_lists.c:60 [inline]
 __hw_addr_add_ex+0x2e5/0x9e0 net/core/dev_addr_lists.c:118
 __dev_mc_add net/core/dev_addr_lists.c:867 [inline]
 dev_mc_add+0x9a/0x130 net/core/dev_addr_lists.c:885
 igmp6_group_added+0x267/0xbc0 net/ipv6/mcast.c:680
 ipv6_mc_up+0x296/0x3b0 net/ipv6/mcast.c:2752
 ipv6_mc_remap+0x1e/0x30 net/ipv6/mcast.c:2706
 addrconf_type_change net/ipv6/addrconf.c:3768 [inline]
 addrconf_notify+0x4c6/0x1c40 net/ipv6/addrconf.c:3736
 notifier_call_chain kernel/notifier.c:93 [inline]
 raw_notifier_call_chain+0xe4/0x430 kernel/notifier.c:461
 call_netdevice_notifiers_info net/core/dev.c:1970 [inline]
 call_netdevice_notifiers_extack net/core/dev.c:2008 [inline]
 call_netdevice_notifiers+0x1ee/0x2d0 net/core/dev.c:2022
 bond_enslave+0xb88/0x5240 drivers/net/bonding/bond_main.c:1913
 do_set_master net/core/rtnetlink.c:2674 [inline]
 rtnl_newlink_create net/core/rtnetlink.c:3502 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3705 [inline]
 rtnl_newlink+0x3924/0x4110 net/core/rtnetlink.c:3718
 rtnetlink_rcv_msg+0x16a6/0x1840 net/core/rtnetlink.c:6444
 netlink_rcv_skb+0x371/0x650 net/netlink/af_netlink.c:2545
 rtnetlink_rcv+0x34/0x40 net/core/rtnetlink.c:6462
 netlink_unicast_kernel net/netlink/af_netlink.c:1342 [inline]
 netlink_unicast+0xf47/0x1250 net/netlink/af_netlink.c:1368
 netlink_sendmsg+0x1238/0x13d0 net/netlink/af_netlink.c:1910
 sock_sendmsg_nosec net/socket.c:730 [inline]
 sock_sendmsg net/socket.c:753 [inline]
 ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2541
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2595
 __sys_sendmsg net/socket.c:2624 [inline]
 __do_sys_sendmsg net/socket.c:2633 [inline]
 __se_sys_sendmsg net/socket.c:2631 [inline]
 __x64_sys_sendmsg+0x307/0x490 net/socket.c:2631
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

CPU: 1 PID: 28143 Comm: syz-executor.3 Not tainted 6.6.0-rc2-syzkaller-00018-g2cf0f7156238 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023
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