KASAN: slab-out-of-bounds Read in hci_le_meta_evt (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3c8c2309 Linux 4.19.190
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=10391ffbd00000
kernel config: https://syzkaller.appspot.com/x/.config?x=d3c2572d41264a3d
dashboard link: https://syzkaller.appspot.com/bug?extid=9247eb9ed460108a8883
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=14540663d00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1060fc53d00000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+9247eb...@syzkaller.appspotmail.com

Bluetooth: hci0: Dropping invalid advertising data
==================================================================
BUG: KASAN: slab-out-of-bounds in hci_le_adv_report_evt net/bluetooth/hci_event.c:5336 [inline]
BUG: KASAN: slab-out-of-bounds in hci_le_meta_evt+0x363d/0x3e00 net/bluetooth/hci_event.c:5636
Read of size 1 at addr ffff8880a8d5299a by task kworker/u5:1/8105

CPU: 1 PID: 8105 Comm: kworker/u5:1 Not tainted 4.19.190-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: hci0 hci_rx_work
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
print_address_description.cold+0x54/0x219 mm/kasan/report.c:256
kasan_report_error.cold+0x8a/0x1b9 mm/kasan/report.c:354
kasan_report mm/kasan/report.c:412 [inline]
__asan_report_load1_noabort+0x88/0x90 mm/kasan/report.c:430
hci_le_adv_report_evt net/bluetooth/hci_event.c:5336 [inline]
hci_le_meta_evt+0x363d/0x3e00 net/bluetooth/hci_event.c:5636
hci_event_packet+0x34ad/0x7e20 net/bluetooth/hci_event.c:5901
hci_rx_work+0x4ad/0xc70 net/bluetooth/hci_core.c:4361
process_one_work+0x864/0x1570 kernel/workqueue.c:2152
worker_thread+0x64c/0x1130 kernel/workqueue.c:2295
kthread+0x33f/0x460 kernel/kthread.c:259
ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415

Allocated by task 9216:
__do_kmalloc_node mm/slab.c:3689 [inline]
__kmalloc_node_track_caller+0x4c/0x70 mm/slab.c:3703
__kmalloc_reserve net/core/skbuff.c:137 [inline]
__alloc_skb+0xae/0x560 net/core/skbuff.c:205
alloc_skb include/linux/skbuff.h:995 [inline]
bt_skb_alloc include/net/bluetooth/bluetooth.h:339 [inline]
vhci_get_user drivers/bluetooth/hci_vhci.c:180 [inline]
vhci_write+0xbd/0x450 drivers/bluetooth/hci_vhci.c:299
call_write_iter include/linux/fs.h:1821 [inline]
new_sync_write fs/read_write.c:474 [inline]
__vfs_write+0x51b/0x770 fs/read_write.c:487
vfs_write+0x1f3/0x540 fs/read_write.c:549
ksys_write+0x12b/0x2a0 fs/read_write.c:599
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe

Freed by task 4698:
__cache_free mm/slab.c:3503 [inline]
kfree+0xcc/0x210 mm/slab.c:3822
skb_free_head net/core/skbuff.c:563 [inline]
skb_release_data+0x6de/0x920 net/core/skbuff.c:583
skb_release_all net/core/skbuff.c:640 [inline]
__kfree_skb net/core/skbuff.c:654 [inline]
consume_skb+0x113/0x3d0 net/core/skbuff.c:714
skb_free_datagram+0x16/0xf0 net/core/datagram.c:329
netlink_recvmsg+0x627/0xea0 net/netlink/af_netlink.c:1988
sock_recvmsg_nosec net/socket.c:795 [inline]
sock_recvmsg net/socket.c:802 [inline]
sock_recvmsg+0xca/0x110 net/socket.c:798
___sys_recvmsg+0x255/0x570 net/socket.c:2277
__sys_recvmsg net/socket.c:2326 [inline]
__do_sys_recvmsg net/socket.c:2336 [inline]
__se_sys_recvmsg net/socket.c:2333 [inline]
__x64_sys_recvmsg+0x12f/0x220 net/socket.c:2333
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe

The buggy address belongs to the object at ffff8880a8d52780
which belongs to the cache kmalloc-512 of size 512
The buggy address is located 26 bytes to the right of
512-byte region [ffff8880a8d52780, ffff8880a8d52980)
The buggy address belongs to the page:
page:ffffea0002a35480 count:1 mapcount:0 mapping:ffff88813bff0940 index:0x0
flags: 0xfff00000000100(slab)
raw: 00fff00000000100 ffffea0002a73548 ffffea0002a4d308 ffff88813bff0940
raw: 0000000000000000 ffff8880a8d52000 0000000100000006 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff8880a8d52880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffff8880a8d52900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8880a8d52980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
^
ffff8880a8d52a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880a8d52a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================


---
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.
syzbot can test patches for this issue, for details see:
https://goo.gl/tpsmEJ#testing-patches