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

[syzbot <syzbot+6ea290ba76d8c1eb1ac2@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    2c9b3512402e Merge tag 'for-linus' of git://git.kernel.org..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12628cad980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=6bfb33a8ad10458f
dashboard link: https://syzkaller.appspot.com/bug?extid=6ea290ba76d8c1eb1ac2
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: i386

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/9593db3ad921/disk-2c9b3512.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/77c4ed0c2bb7/vmlinux-2c9b3512.xz
kernel image: https://storage.googleapis.com/syzbot-assets/b1e492f9354b/bzImage-2c9b3512.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+6ea290ba76d8c1eb1ac2@syzkaller.appspotmail.com

=====================================================
BUG: KMSAN: uninit-value in hci_scodata_packet net/bluetooth/hci_core.c:3835 [inline]
BUG: KMSAN: uninit-value in hci_rx_work+0x10a8/0x1130 net/bluetooth/hci_core.c:4039
 hci_scodata_packet net/bluetooth/hci_core.c:3835 [inline]
 hci_rx_work+0x10a8/0x1130 net/bluetooth/hci_core.c:4039
 process_one_work kernel/workqueue.c:3231 [inline]
 process_scheduled_works+0xae0/0x1c40 kernel/workqueue.c:3312
 worker_thread+0xea5/0x1520 kernel/workqueue.c:3390
 kthread+0x3e2/0x540 kernel/kthread.c:389
 ret_from_fork+0x6d/0x90 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:3985 [inline]
 slab_alloc_node mm/slub.c:4028 [inline]
 kmem_cache_alloc_node_noprof+0x6bf/0xb80 mm/slub.c:4071
 kmalloc_reserve+0x13d/0x4a0 net/core/skbuff.c:583
 __alloc_skb+0x363/0x7b0 net/core/skbuff.c:674
 alloc_skb include/linux/skbuff.h:1320 [inline]
 bt_skb_alloc include/net/bluetooth/bluetooth.h:493 [inline]
 vhci_get_user drivers/bluetooth/hci_vhci.c:489 [inline]
 vhci_write+0x128/0x910 drivers/bluetooth/hci_vhci.c:609
 new_sync_write fs/read_write.c:497 [inline]
 vfs_write+0xb2f/0x1550 fs/read_write.c:590
 ksys_write+0x20f/0x4c0 fs/read_write.c:643
 __do_sys_write fs/read_write.c:655 [inline]
 __se_sys_write fs/read_write.c:652 [inline]
 __ia32_sys_write+0x91/0xe0 fs/read_write.c:652
 ia32_sys_call+0x2e34/0x40d0 arch/x86/include/generated/asm/syscalls_32.h:5
 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline]
 __do_fast_syscall_32+0xb0/0x110 arch/x86/entry/common.c:386
 do_fast_syscall_32+0x38/0x80 arch/x86/entry/common.c:411
 do_SYSENTER_32+0x1f/0x30 arch/x86/entry/common.c:449
 entry_SYSENTER_compat_after_hwframe+0x84/0x8e

CPU: 1 PID: 5058 Comm: kworker/u9:6 Not tainted 6.10.0-syzkaller-11185-g2c9b3512402e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/27/2024
Workqueue: hci3 hci_rx_work
=====================================================


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