{"id":"CVE-2023-53863","summary":"netlink: do not hard code device address lenth in fdb dumps","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetlink: do not hard code device address lenth in fdb dumps\n\nsyzbot reports that some netdev devices do not have a six bytes\naddress [1]\n\nReplace ETH_ALEN by dev-\u003eaddr_len.\n\n[1] (Case of a device where dev-\u003eaddr_len = 4)\n\nBUG: KMSAN: kernel-infoleak in instrument_copy_to_user include/linux/instrumented.h:114 [inline]\nBUG: KMSAN: kernel-infoleak in copyout+0xb8/0x100 lib/iov_iter.c:169\ninstrument_copy_to_user include/linux/instrumented.h:114 [inline]\ncopyout+0xb8/0x100 lib/iov_iter.c:169\n_copy_to_iter+0x6d8/0x1d00 lib/iov_iter.c:536\ncopy_to_iter include/linux/uio.h:206 [inline]\nsimple_copy_to_iter+0x68/0xa0 net/core/datagram.c:513\n__skb_datagram_iter+0x123/0xdc0 net/core/datagram.c:419\nskb_copy_datagram_iter+0x5c/0x200 net/core/datagram.c:527\nskb_copy_datagram_msg include/linux/skbuff.h:3960 [inline]\nnetlink_recvmsg+0x4ae/0x15a0 net/netlink/af_netlink.c:1970\nsock_recvmsg_nosec net/socket.c:1019 [inline]\nsock_recvmsg net/socket.c:1040 [inline]\n____sys_recvmsg+0x283/0x7f0 net/socket.c:2722\n___sys_recvmsg+0x223/0x840 net/socket.c:2764\ndo_recvmmsg+0x4f9/0xfd0 net/socket.c:2858\n__sys_recvmmsg net/socket.c:2937 [inline]\n__do_sys_recvmmsg net/socket.c:2960 [inline]\n__se_sys_recvmmsg net/socket.c:2953 [inline]\n__x64_sys_recvmmsg+0x397/0x490 net/socket.c:2953\ndo_syscall_x64 arch/x86/entry/common.c:50 [inline]\ndo_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80\nentry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nUninit was stored to memory at:\n__nla_put lib/nlattr.c:1009 [inline]\nnla_put+0x1c6/0x230 lib/nlattr.c:1067\nnlmsg_populate_fdb_fill+0x2b8/0x600 net/core/rtnetlink.c:4071\nnlmsg_populate_fdb net/core/rtnetlink.c:4418 [inline]\nndo_dflt_fdb_dump+0x616/0x840 net/core/rtnetlink.c:4456\nrtnl_fdb_dump+0x14ff/0x1fc0 net/core/rtnetlink.c:4629\nnetlink_dump+0x9d1/0x1310 net/netlink/af_netlink.c:2268\nnetlink_recvmsg+0xc5c/0x15a0 net/netlink/af_netlink.c:1995\nsock_recvmsg_nosec+0x7a/0x120 net/socket.c:1019\n____sys_recvmsg+0x664/0x7f0 net/socket.c:2720\n___sys_recvmsg+0x223/0x840 net/socket.c:2764\ndo_recvmmsg+0x4f9/0xfd0 net/socket.c:2858\n__sys_recvmmsg net/socket.c:2937 [inline]\n__do_sys_recvmmsg net/socket.c:2960 [inline]\n__se_sys_recvmmsg net/socket.c:2953 [inline]\n__x64_sys_recvmmsg+0x397/0x490 net/socket.c:2953\ndo_syscall_x64 arch/x86/entry/common.c:50 [inline]\ndo_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80\nentry_SYSCALL_64_after_hwframe+0x63/0xcd\n\nUninit was created at:\nslab_post_alloc_hook+0x12d/0xb60 mm/slab.h:716\nslab_alloc_node mm/slub.c:3451 [inline]\n__kmem_cache_alloc_node+0x4ff/0x8b0 mm/slub.c:3490\nkmalloc_trace+0x51/0x200 mm/slab_common.c:1057\nkmalloc include/linux/slab.h:559 [inline]\n__hw_addr_create net/core/dev_addr_lists.c:60 [inline]\n__hw_addr_add_ex+0x2e5/0x9e0 net/core/dev_addr_lists.c:118\n__dev_mc_add net/core/dev_addr_lists.c:867 [inline]\ndev_mc_add+0x9a/0x130 net/core/dev_addr_lists.c:885\nigmp6_group_added+0x267/0xbc0 net/ipv6/mcast.c:680\nipv6_mc_up+0x296/0x3b0 net/ipv6/mcast.c:2754\nipv6_mc_remap+0x1e/0x30 net/ipv6/mcast.c:2708\naddrconf_type_change net/ipv6/addrconf.c:3731 [inline]\naddrconf_notify+0x4d3/0x1d90 net/ipv6/addrconf.c:3699\nnotifier_call_chain kernel/notifier.c:93 [inline]\nraw_notifier_call_chain+0xe4/0x430 kernel/notifier.c:461\ncall_netdevice_notifiers_info net/core/dev.c:1935 [inline]\ncall_netdevice_notifiers_extack net/core/dev.c:1973 [inline]\ncall_netdevice_notifiers+0x1ee/0x2d0 net/core/dev.c:1987\nbond_enslave+0xccd/0x53f0 drivers/net/bonding/bond_main.c:1906\ndo_set_master net/core/rtnetlink.c:2626 [inline]\nrtnl_newlink_create net/core/rtnetlink.c:3460 [inline]\n__rtnl_newlink net/core/rtnetlink.c:3660 [inline]\nrtnl_newlink+0x378c/0x40e0 net/core/rtnetlink.c:3673\nrtnetlink_rcv_msg+0x16a6/0x1840 net/core/rtnetlink.c:6395\nnetlink_rcv_skb+0x371/0x650 net/netlink/af_netlink.c:2546\nrtnetlink_rcv+0x34/0x40 net/core/rtnetlink.c:6413\nnetlink_unicast_kernel net/netlink/af_netlink.c:1339 [inline]\nnetlink_unicast+0xf28/0x1230 net/netlink/af_\n---truncated---","modified":"2026-04-02T09:45:26.236692Z","published":"2025-12-09T01:30:32.109Z","related":["SUSE-SU-2026:0278-1","SUSE-SU-2026:0281-1","SUSE-SU-2026:0293-1","SUSE-SU-2026:0315-1","SUSE-SU-2026:0473-1","SUSE-SU-2026:20477-1","SUSE-SU-2026:20498-1","SUSE-SU-2026:20845-1","SUSE-SU-2026:20876-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/53xxx/CVE-2023-53863.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/44db85c6e1a184b99a2cdf56b525ac63c4962c22"},{"type":"WEB","url":"https://git.kernel.org/stable/c/619384319b137908d1008c92426c9daa95c06b90"},{"type":"WEB","url":"https://git.kernel.org/stable/c/61d1bf3c34bf5fe936c50d1a4bc460babcc85e88"},{"type":"WEB","url":"https://git.kernel.org/stable/c/73862118bd9dec850aa8e775145647ddd23aedf8"},{"type":"WEB","url":"https://git.kernel.org/stable/c/aa5406950726e336c5c9585b09799a734b6e77bf"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b6f2d4618fc697886ad41e215ae20638153e42d0"},{"type":"WEB","url":"https://git.kernel.org/stable/c/bd1de6107f10e7d4c2aabe3397b58d63672fc511"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c3ad49ff5c030cbe719fc4cb0ae081b8255ef4b3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/e9331c8fa4c69f09d2c71682af75586f77266e81"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2023/53xxx/CVE-2023-53863.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2023-53863"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"d83b060360485454fcd6870340ec01d6f96f2295"},{"fixed":"61d1bf3c34bf5fe936c50d1a4bc460babcc85e88"},{"fixed":"c3ad49ff5c030cbe719fc4cb0ae081b8255ef4b3"},{"fixed":"bd1de6107f10e7d4c2aabe3397b58d63672fc511"},{"fixed":"44db85c6e1a184b99a2cdf56b525ac63c4962c22"},{"fixed":"619384319b137908d1008c92426c9daa95c06b90"},{"fixed":"e9331c8fa4c69f09d2c71682af75586f77266e81"},{"fixed":"b6f2d4618fc697886ad41e215ae20638153e42d0"},{"fixed":"73862118bd9dec850aa8e775145647ddd23aedf8"},{"fixed":"aa5406950726e336c5c9585b09799a734b6e77bf"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-53863.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"3.5.0"},{"fixed":"4.14.322"}]},{"type":"ECOSYSTEM","events":[{"introduced":"4.15.0"},{"fixed":"4.19.291"}]},{"type":"ECOSYSTEM","events":[{"introduced":"4.20.0"},{"fixed":"5.4.251"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.5.0"},{"fixed":"5.10.188"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.121"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.39"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.3.13"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.4.0"},{"fixed":"6.4.4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2023-53863.json"}}],"schema_version":"1.7.5"}