[syzbot] [bluetooth?] KMSAN: uninit-value in eir_get_service_data

[syzbot] [bluetooth?] KMSAN: uninit-value in eir_get_service_data

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    c42d9eeef8e5 Merge tag 'hardening-v6.7-rc2' of git://git.k..
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=16867338e80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=fdfc68946ad7a215
dashboard link: https://syzkaller.appspot.com/bug?extid=5e132fbe94a9ede456ad
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=178f3388e80000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=13341388e80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/8c25bb76d765/disk-c42d9eee.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/80d9450a6b6a/vmlinux-c42d9eee.xz
kernel image: https://storage.googleapis.com/syzbot-assets/4b1a54cf685f/bzImage-c42d9eee.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+5e132fbe94a9ede456ad@syzkaller.appspotmail.com

=====================================================
BUG: KMSAN: uninit-value in eir_get_data net/bluetooth/eir.h:73 [inline]
BUG: KMSAN: uninit-value in eir_get_service_data+0x25c/0x570 net/bluetooth/eir.c:384
 eir_get_data net/bluetooth/eir.h:73 [inline]
 eir_get_service_data+0x25c/0x570 net/bluetooth/eir.c:384
 iso_connect_ind+0x2004/0x2330 net/bluetooth/iso.c:1794
 hci_proto_connect_ind include/net/bluetooth/hci_core.h:1922 [inline]
 hci_le_per_adv_report_evt+0xc0/0x1e0 net/bluetooth/hci_event.c:6645
 hci_le_meta_evt+0x608/0x860 net/bluetooth/hci_event.c:7344
 hci_event_func net/bluetooth/hci_event.c:7674 [inline]
 hci_event_packet+0x1183/0x1be0 net/bluetooth/hci_event.c:7729
 hci_rx_work+0x687/0x1120 net/bluetooth/hci_core.c:4105
 process_one_work kernel/workqueue.c:2630 [inline]
 process_scheduled_works+0x104e/0x1e70 kernel/workqueue.c:2703
 worker_thread+0xf45/0x1490 kernel/workqueue.c:2784
 kthread+0x3ed/0x540 kernel/kthread.c:388
 ret_from_fork+0x66/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242

Uninit was created at:
 slab_post_alloc_hook+0x129/0xa70 mm/slab.h:768
 slab_alloc_node mm/slub.c:3478 [inline]
 kmem_cache_alloc_node+0x5e9/0xb10 mm/slub.c:3523
 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:560
 __alloc_skb+0x318/0x740 net/core/skbuff.c:651
 alloc_skb include/linux/skbuff.h:1286 [inline]
 bt_skb_alloc include/net/bluetooth/bluetooth.h:487 [inline]
 vhci_get_user drivers/bluetooth/hci_vhci.c:495 [inline]
 vhci_write+0x126/0x8f0 drivers/bluetooth/hci_vhci.c:615
 call_write_iter include/linux/fs.h:2020 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x8ef/0x1490 fs/read_write.c:584
 ksys_write+0x20f/0x4c0 fs/read_write.c:637
 __do_sys_write fs/read_write.c:649 [inline]
 __se_sys_write fs/read_write.c:646 [inline]
 __x64_sys_write+0x93/0xd0 fs/read_write.c:646
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x44/0x110 arch/x86/entry/common.c:82
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

CPU: 1 PID: 4386 Comm: kworker/u5:1 Not tainted 6.7.0-rc1-syzkaller-00019-gc42d9eeef8e5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/10/2023
Workqueue: hci0 hci_rx_work
=====================================================


---
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