KMSAN: uninit-value in __tipc_nl_bearer_enable (2)

[yshigeru]

https://syzkaller.appspot.com/bug?extid=9425c47dccbcb4c17d51

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BUG: KMSAN: uninit-value in strscpy+0xc4/0x160
 strscpy+0xc4/0x160
 bearer_name_validate net/tipc/bearer.c:147 [inline]
 tipc_enable_bearer net/tipc/bearer.c:259 [inline]
 __tipc_nl_bearer_enable+0x634/0x2220 net/tipc/bearer.c:1043
 tipc_nl_bearer_enable+0x3c/0x70 net/tipc/bearer.c:1052
 genl_family_rcv_msg_doit net/netlink/genetlink.c:971 [inline]
 genl_family_rcv_msg net/netlink/genetlink.c:1051 [inline]
 genl_rcv_msg+0x11ec/0x1290 net/netlink/genetlink.c:1066
 netlink_rcv_skb+0x371/0x650 net/netlink/af_netlink.c:2545
 genl_rcv+0x40/0x60 net/netlink/genetlink.c:1075
 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:2540
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2594
 __sys_sendmsg net/socket.c:2623 [inline]
 __do_sys_sendmsg net/socket.c:2632 [inline]
 __se_sys_sendmsg net/socket.c:2630 [inline]
 __x64_sys_sendmsg+0x307/0x490 net/socket.c:2630
 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+0x577/0xa80 mm/slub.c:3523
 kmalloc_reserve+0x148/0x470 net/core/skbuff.c:559
 __alloc_skb+0x318/0x740 net/core/skbuff.c:644
 alloc_skb include/linux/skbuff.h:1286 [inline]
 netlink_alloc_large_skb net/netlink/af_netlink.c:1214 [inline]
 netlink_sendmsg+0xb34/0x13d0 net/netlink/af_netlink.c:1885
 sock_sendmsg_nosec net/socket.c:730 [inline]
 sock_sendmsg net/socket.c:753 [inline]
 ____sys_sendmsg+0x9c2/0xd60 net/socket.c:2540
 ___sys_sendmsg+0x28d/0x3c0 net/socket.c:2594
 __sys_sendmsg net/socket.c:2623 [inline]
 __do_sys_sendmsg net/socket.c:2632 [inline]
 __se_sys_sendmsg net/socket.c:2630 [inline]
 __x64_sys_sendmsg+0x307/0x490 net/socket.c:2630
 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: 4993 Comm: syz-executor386 Not tainted 6.5.0-syzkaller-12145-g4a0fc73da97e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
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[yshigeru]

Sent the patch: https://lore.kernel.org/all/20230926125120.152133-1-syoshida@redhat.com/

[yshigeru]

Resolved by #10