[syzbot] [bluetooth?] KASAN: slab-out-of-bounds Read in hci_sock_setsockopt

From: syzbot
Date: Fri Apr 05 2024 - 02:56:51 EST

Hello,

syzbot found the following issue on:

HEAD commit: fe46a7dd189e Merge tag 'sound-6.9-rc1' of git://git.kernel..
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=13ee9103180000
kernel config: https://syzkaller.appspot.com/x/.config?x=4d90a36f0cab495a
dashboard link: https://syzkaller.appspot.com/bug?extid=837ba09d9db969068367
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=15807005180000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=1777929d180000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/f6c04726a2ae/disk-fe46a7dd.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/09c26ce901ea/vmlinux-fe46a7dd.xz
kernel image: https://storage.googleapis.com/syzbot-assets/134acf7f5322/bzImage-fe46a7dd.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+837ba09d9db969068367@xxxxxxxxxxxxxxxxxxxxxxxxx

==================================================================
BUG: KASAN: slab-out-of-bounds in copy_from_sockptr_offset include/linux/sockptr.h:49 [inline]
BUG: KASAN: slab-out-of-bounds in copy_from_sockptr include/linux/sockptr.h:55 [inline]
BUG: KASAN: slab-out-of-bounds in hci_sock_setsockopt_old net/bluetooth/hci_sock.c:1949 [inline]
BUG: KASAN: slab-out-of-bounds in hci_sock_setsockopt+0xe28/0xf70 net/bluetooth/hci_sock.c:2024
Read of size 4 at addr ffff88801979fec3 by task syz-executor243/5060

CPU: 1 PID: 5060 Comm: syz-executor243 Not tainted 6.8.0-syzkaller-08951-gfe46a7dd189e #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
print_address_description mm/kasan/report.c:377 [inline]
print_report+0x169/0x550 mm/kasan/report.c:488
kasan_report+0x143/0x180 mm/kasan/report.c:601
copy_from_sockptr_offset include/linux/sockptr.h:49 [inline]
copy_from_sockptr include/linux/sockptr.h:55 [inline]
hci_sock_setsockopt_old net/bluetooth/hci_sock.c:1949 [inline]
hci_sock_setsockopt+0xe28/0xf70 net/bluetooth/hci_sock.c:2024
do_sock_setsockopt+0x3af/0x720 net/socket.c:2311
__sys_setsockopt+0x1ae/0x250 net/socket.c:2334
__do_sys_setsockopt net/socket.c:2343 [inline]
__se_sys_setsockopt net/socket.c:2340 [inline]
__x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2340
do_syscall_64+0xfb/0x240
entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7f1e9e9add89
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 91 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff645fbe38 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f1e9e9add89
RDX: 0000000000000001 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000000002 R09: 0000000000000000
R10: 0000000020000040 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>

Allocated by task 5060:
kasan_save_stack mm/kasan/common.c:47 [inline]
kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
__kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:387
kasan_kmalloc include/linux/kasan.h:211 [inline]
__do_kmalloc_node mm/slub.c:3966 [inline]
__kmalloc+0x233/0x4a0 mm/slub.c:3979
kmalloc include/linux/slab.h:632 [inline]
__cgroup_bpf_run_filter_setsockopt+0xd2f/0x1040 kernel/bpf/cgroup.c:1869
do_sock_setsockopt+0x6b4/0x720 net/socket.c:2293
__sys_setsockopt+0x1ae/0x250 net/socket.c:2334
__do_sys_setsockopt net/socket.c:2343 [inline]
__se_sys_setsockopt net/socket.c:2340 [inline]
__x64_sys_setsockopt+0xb5/0xd0 net/socket.c:2340
do_syscall_64+0xfb/0x240
entry_SYSCALL_64_after_hwframe+0x6d/0x75

The buggy address belongs to the object at ffff88801979fec0
which belongs to the cache kmalloc-8 of size 8
The buggy address is located 1 bytes to the right of
allocated 2-byte region [ffff88801979fec0, ffff88801979fec2)

The buggy address belongs to the physical page:
page:ffffea000065e7c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1979f
anon flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000800 ffff888014c41280 0000000000000000 dead000000000001
raw: 0000000000000000 0000000080800080 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12c40(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY), pid 26, tgid 26 (kdevtmpfs), ts 7021029367, free_ts 0
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1533
prep_new_page mm/page_alloc.c:1540 [inline]
get_page_from_freelist+0x33ea/0x3580 mm/page_alloc.c:3311
__alloc_pages+0x256/0x680 mm/page_alloc.c:4569
__alloc_pages_node include/linux/gfp.h:238 [inline]
alloc_pages_node include/linux/gfp.h:261 [inline]
alloc_slab_page+0x5f/0x160 mm/slub.c:2175
allocate_slab mm/slub.c:2338 [inline]
new_slab+0x84/0x2f0 mm/slub.c:2391
___slab_alloc+0xc73/0x1260 mm/slub.c:3525
__slab_alloc mm/slub.c:3610 [inline]
__slab_alloc_node mm/slub.c:3663 [inline]
slab_alloc_node mm/slub.c:3835 [inline]
__do_kmalloc_node mm/slub.c:3965 [inline]
__kmalloc_node_track_caller+0x2d6/0x4e0 mm/slub.c:3986
kstrdup+0x3a/0x80 mm/util.c:62
smack_inode_init_security+0x5d7/0x740 security/smack/smack_lsm.c:1053
security_inode_init_security+0x1a2/0x440 security/security.c:1722
shmem_mknod+0xc5/0x1d0 mm/shmem.c:3282
vfs_mknod+0x36d/0x3b0 fs/namei.c:4001
handle_create drivers/base/devtmpfs.c:219 [inline]
handle drivers/base/devtmpfs.c:384 [inline]
devtmpfs_work_loop+0x95c/0x1030 drivers/base/devtmpfs.c:399
devtmpfsd+0x4c/0x50 drivers/base/devtmpfs.c:441
kthread+0x2f0/0x390 kernel/kthread.c:388
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
page_owner free stack trace missing

Memory state around the buggy address:
ffff88801979fd80: 06 fc fc fc 05 fc fc fc 06 fc fc fc 06 fc fc fc
ffff88801979fe00: 06 fc fc fc 05 fc fc fc 06 fc fc fc 06 fc fc fc
>ffff88801979fe80: 06 fc fc fc 05 fc fc fc 02 fc fc fc 06 fc fc fc
^
ffff88801979ff00: 06 fc fc fc 06 fc fc fc 05 fc fc fc fa fc fc fc
ffff88801979ff80: 06 fc fc fc 06 fc fc fc 06 fc fc fc 05 fc fc fc
==================================================================


---
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