Subject: [syzbot] KMSAN: uninit-value in tipc_nl_compat_name_table_dump (3)

From: syzbot <[email-masked]>
Date: Thu, 03 Nov 2022 09:22:41 -0700

Hello,

syzbot found the following issue on:

HEAD commit:    8f4ae27df775 Revert "Revert "crypto: kmsan: disable accele..
git tree:       https://github.com/google/kmsan.git master
console+strace: https://syzkaller.appspot.com/x/log.txt?x=142d16cf080000
kernel config:  https://syzkaller.appspot.com/x/.config?x=121c7ef28ec597bd
dashboard link: https://syzkaller.appspot.com/bug?extid=e5dbaaa238680ce206ea
compiler:       clang version 15.0.0 (https://github.com/llvm/llvm-project.git 610139d2d9ce6746b3c617fb3e2f7886272d26ff), GNU ld (GNU Binutils for Debian) 2.35.2
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=176a716f080000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=140256a0880000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email-masked]

=====================================================
BUG: KMSAN: uninit-value in tipc_nl_compat_name_table_dump+0x841/0xea0 net/tipc/netlink_compat.c:934
 tipc_nl_compat_name_table_dump+0x841/0xea0 net/tipc/netlink_compat.c:934
 __tipc_nl_compat_dumpit+0xab2/0x1320 net/tipc/netlink_compat.c:238
 tipc_nl_compat_dumpit+0x991/0xb50 net/tipc/netlink_compat.c:321
 tipc_nl_compat_recv+0xb6e/0x1640 net/tipc/netlink_compat.c:1324
 genl_family_rcv_msg_doit net/netlink/genetlink.c:731 [inline]
 genl_family_rcv_msg net/netlink/genetlink.c:775 [inline]
 genl_rcv_msg+0x103f/0x1260 net/netlink/genetlink.c:792
 netlink_rcv_skb+0x3a5/0x6c0 net/netlink/af_netlink.c:2501
 genl_rcv+0x3c/0x50 net/netlink/genetlink.c:803
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0xf3b/0x1270 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x1288/0x1440 net/netlink/af_netlink.c:1921
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg net/socket.c:734 [inline]
 ____sys_sendmsg+0xabc/0xe90 net/socket.c:2482
 ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2536
 __sys_sendmsg net/socket.c:2565 [inline]
 __do_sys_sendmsg net/socket.c:2574 [inline]
 __se_sys_sendmsg net/socket.c:2572 [inline]
 __x64_sys_sendmsg+0x367/0x540 net/socket.c:2572
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Uninit was created at:
 slab_post_alloc_hook mm/slab.h:732 [inline]
 slab_alloc_node mm/slub.c:3258 [inline]
 __kmalloc_node_track_caller+0x814/0x1250 mm/slub.c:4970
 kmalloc_reserve net/core/skbuff.c:362 [inline]
 __alloc_skb+0x346/0xcf0 net/core/skbuff.c:434
 alloc_skb include/linux/skbuff.h:1257 [inline]
 netlink_alloc_large_skb net/netlink/af_netlink.c:1191 [inline]
 netlink_sendmsg+0xb71/0x1440 net/netlink/af_netlink.c:1896
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg net/socket.c:734 [inline]
 ____sys_sendmsg+0xabc/0xe90 net/socket.c:2482
 ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2536
 __sys_sendmsg net/socket.c:2565 [inline]
 __do_sys_sendmsg net/socket.c:2574 [inline]
 __se_sys_sendmsg net/socket.c:2572 [inline]
 __x64_sys_sendmsg+0x367/0x540 net/socket.c:2572
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

CPU: 1 PID: 3490 Comm: syz-executor155 Not tainted 6.0.0-rc5-syzkaller-48538-g8f4ae27df775 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
=====================================================

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