[syzbot] [net?] [nfc?] KMSAN: uninit-value in nci_dev_up (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: e1914add2799 Merge tag 'for-linus' of git://git.kernel.org..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=10eee996580000
kernel config: https://syzkaller.appspot.com/x/.config?x=a9f364ffbbe4c1e9
dashboard link: https://syzkaller.appspot.com/bug?extid=46ca2592193f2fb3debc
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/841025ab4e0a/disk-e1914add.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/cf76ff829fea/vmlinux-e1914add.xz
kernel image: https://storage.googleapis.com/syzbot-assets/9e13b4488bea/bzImage-e1914add.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+46ca25...@syzkaller.appspotmail.com

=====================================================
BUG: KMSAN: uninit-value in nci_init_complete_req net/nfc/nci/core.c:192 [inline]
BUG: KMSAN: uninit-value in __nci_request net/nfc/nci/core.c:108 [inline]
BUG: KMSAN: uninit-value in nci_open_device net/nfc/nci/core.c:529 [inline]
BUG: KMSAN: uninit-value in nci_dev_up+0x1110/0x1bb0 net/nfc/nci/core.c:643
nci_init_complete_req net/nfc/nci/core.c:192 [inline]
__nci_request net/nfc/nci/core.c:108 [inline]
nci_open_device net/nfc/nci/core.c:529 [inline]
nci_dev_up+0x1110/0x1bb0 net/nfc/nci/core.c:643
nfc_dev_up+0x204/0x3d0 net/nfc/core.c:118
nfc_genl_dev_up+0xe9/0x1c0 net/nfc/netlink.c:775
genl_family_rcv_msg_doit+0x338/0x3f0 net/netlink/genetlink.c:1114
genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
genl_rcv_msg+0xac5/0xc00 net/netlink/genetlink.c:1209
netlink_rcv_skb+0x54d/0x680 net/netlink/af_netlink.c:2550
genl_rcv+0x41/0x60 net/netlink/genetlink.c:1218
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0xee2/0x1290 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x10b2/0x1250 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:787 [inline]
__sock_sendmsg net/socket.c:802 [inline]
____sys_sendmsg+0xf37/0xfd0 net/socket.c:2698
___sys_sendmsg+0x271/0x3b0 net/socket.c:2752
__sys_sendmsg net/socket.c:2784 [inline]
__do_sys_sendmsg net/socket.c:2789 [inline]
__se_sys_sendmsg net/socket.c:2787 [inline]
__x64_sys_sendmsg+0x211/0x3e0 net/socket.c:2787
x64_sys_call+0x1e20/0x3ea0 arch/x86/include/generated/asm/syscalls_64.h:47
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x134/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
nci_init_complete_req net/nfc/nci/core.c:192 [inline]
__nci_request net/nfc/nci/core.c:108 [inline]
nci_open_device net/nfc/nci/core.c:529 [inline]
nci_dev_up+0x1109/0x1bb0 net/nfc/nci/core.c:643
nfc_dev_up+0x204/0x3d0 net/nfc/core.c:118
nfc_genl_dev_up+0xe9/0x1c0 net/nfc/netlink.c:775
genl_family_rcv_msg_doit+0x338/0x3f0 net/netlink/genetlink.c:1114
genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline]
genl_rcv_msg+0xac5/0xc00 net/netlink/genetlink.c:1209
netlink_rcv_skb+0x54d/0x680 net/netlink/af_netlink.c:2550
genl_rcv+0x41/0x60 net/netlink/genetlink.c:1218
netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
netlink_unicast+0xee2/0x1290 net/netlink/af_netlink.c:1344
netlink_sendmsg+0x10b2/0x1250 net/netlink/af_netlink.c:1894
sock_sendmsg_nosec net/socket.c:787 [inline]
__sock_sendmsg net/socket.c:802 [inline]
____sys_sendmsg+0xf37/0xfd0 net/socket.c:2698
___sys_sendmsg+0x271/0x3b0 net/socket.c:2752
__sys_sendmsg net/socket.c:2784 [inline]
__do_sys_sendmsg net/socket.c:2789 [inline]
__se_sys_sendmsg net/socket.c:2787 [inline]
__x64_sys_sendmsg+0x211/0x3e0 net/socket.c:2787
x64_sys_call+0x1e20/0x3ea0 arch/x86/include/generated/asm/syscalls_64.h:47
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x134/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
nci_core_init_rsp_packet_v2 net/nfc/nci/rsp.c:107 [inline]
nci_core_init_rsp_packet net/nfc/nci/rsp.c:131 [inline]
nci_rsp_packet+0x2c3b/0x2d70 net/nfc/nci/rsp.c:376
nci_rx_work+0x48f/0x850 net/nfc/nci/core.c:1579
process_one_work kernel/workqueue.c:3302 [inline]
process_scheduled_works+0xb65/0x1e40 kernel/workqueue.c:3385
worker_thread+0xee4/0x1590 kernel/workqueue.c:3466
kthread+0x53f/0x600 kernel/kthread.c:436
ret_from_fork+0x20f/0x8d0 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Uninit was created at:
slab_post_alloc_hook mm/slub.c:4576 [inline]
slab_alloc_node mm/slub.c:4898 [inline]
kmem_cache_alloc_node_noprof+0x3cd/0x12c0 mm/slub.c:4950
kmalloc_reserve net/core/skbuff.c:613 [inline]
__alloc_skb+0x855/0x1190 net/core/skbuff.c:713
alloc_skb include/linux/skbuff.h:1383 [inline]
virtual_ncidev_write+0x6b/0x2a0 drivers/nfc/virtual_ncidev.c:120
vfs_write+0x48a/0x15c0 fs/read_write.c:686
ksys_write+0x1d9/0x470 fs/read_write.c:740
__do_sys_write fs/read_write.c:751 [inline]
__se_sys_write fs/read_write.c:748 [inline]
__x64_sys_write+0x97/0xf0 fs/read_write.c:748
x64_sys_call+0x2ff0/0x3ea0 arch/x86/include/generated/asm/syscalls_64.h:2
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x134/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

CPU: 1 UID: 0 PID: 7976 Comm: syz.2.570 Not tainted syzkaller #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
=====================================================


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzk...@googlegroups.com.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup