syzbot


KASAN: slab-use-after-free Write in sco_conn_put

Status: upstream: reported on 2024/12/02 08:45
Subsystems: bluetooth
[Documentation on labels]
Reported-by: syzbot+55d58a05f0b5fd2ea0c7@syzkaller.appspotmail.com
First crash: 7d18h, last: 3h17m
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [bluetooth?] KASAN: slab-use-after-free Write in sco_conn_put 0 (1) 2024/12/02 08:45

Sample crash report:
==================================================================
BUG: KASAN: slab-use-after-free in sco_conn_free net/bluetooth/sco.c:87 [inline]
BUG: KASAN: slab-use-after-free in kref_put include/linux/kref.h:65 [inline]
BUG: KASAN: slab-use-after-free in sco_conn_put+0xad/0x210 net/bluetooth/sco.c:107
Write of size 8 at addr ffff88805b4555a0 by task syz-executor/7221

CPU: 0 UID: 0 PID: 7221 Comm: syz-executor Not tainted 6.12.0-syzkaller-10724-gaf8edaeddbc5 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x169/0x550 mm/kasan/report.c:489
 kasan_report+0x143/0x180 mm/kasan/report.c:602
 sco_conn_free net/bluetooth/sco.c:87 [inline]
 kref_put include/linux/kref.h:65 [inline]
 sco_conn_put+0xad/0x210 net/bluetooth/sco.c:107
 hci_disconn_cfm include/net/bluetooth/hci_core.h:2050 [inline]
 hci_conn_hash_flush+0xff/0x240 net/bluetooth/hci_conn.c:2698
 hci_dev_close_sync+0xa42/0x11c0 net/bluetooth/hci_sync.c:5212
 hci_dev_do_close net/bluetooth/hci_core.c:483 [inline]
 hci_unregister_dev+0x20b/0x510 net/bluetooth/hci_core.c:2698
 vhci_release+0x80/0xd0 drivers/bluetooth/hci_vhci.c:664
 __fput+0x23c/0xa50 fs/file_table.c:450
 task_work_run+0x24f/0x310 kernel/task_work.c:239
 exit_task_work include/linux/task_work.h:43 [inline]
 do_exit+0xa2f/0x28e0 kernel/exit.c:938
 do_group_exit+0x207/0x2c0 kernel/exit.c:1087
 __do_sys_exit_group kernel/exit.c:1098 [inline]
 __se_sys_exit_group kernel/exit.c:1096 [inline]
 __x64_sys_exit_group+0x3f/0x40 kernel/exit.c:1096
 x64_sys_call+0x26a8/0x26b0 arch/x86/include/generated/asm/syscalls_64.h:232
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f167d17ff19
Code: Unable to access opcode bytes at 0x7f167d17feef.
RSP: 002b:00007ffe98b504f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f167d17ff19
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000043
RBP: 00007f167d1e05b0 R08: 00007ffe98b4e297 R09: 0000000000000003
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
R13: 0000000000000003 R14: 00000000ffffffff R15: 00007ffe98b506a0
 </TASK>

Allocated by task 7448:
 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:377 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394
 kasan_kmalloc include/linux/kasan.h:260 [inline]
 __do_kmalloc_node mm/slub.c:4283 [inline]
 __kmalloc_noprof+0x285/0x4c0 mm/slub.c:4295
 kmalloc_noprof include/linux/slab.h:905 [inline]
 sk_prot_alloc+0xe0/0x210 net/core/sock.c:2165
 sk_alloc+0x38/0x370 net/core/sock.c:2218
 bt_sock_alloc+0x3c/0x340 net/bluetooth/af_bluetooth.c:148
 sco_sock_alloc net/bluetooth/sco.c:549 [inline]
 sco_sock_create+0xbb/0x390 net/bluetooth/sco.c:580
 bt_sock_create+0x161/0x230 net/bluetooth/af_bluetooth.c:132
 __sock_create+0x4c0/0xa30 net/socket.c:1558
 sock_create net/socket.c:1616 [inline]
 __sys_socket_create net/socket.c:1653 [inline]
 __sys_socket+0x150/0x3c0 net/socket.c:1700
 __do_sys_socket net/socket.c:1714 [inline]
 __se_sys_socket net/socket.c:1712 [inline]
 __x64_sys_socket+0x7a/0x90 net/socket.c:1712
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 7454:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:582
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x59/0x70 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2338 [inline]
 slab_free mm/slub.c:4598 [inline]
 kfree+0x196/0x420 mm/slub.c:4746
 sk_prot_free net/core/sock.c:2201 [inline]
 __sk_destruct+0x479/0x5f0 net/core/sock.c:2293
 sco_sock_release+0x25e/0x320 net/bluetooth/sco.c:1308
 __sock_release net/socket.c:640 [inline]
 sock_close+0xbc/0x240 net/socket.c:1408
 __fput+0x23c/0xa50 fs/file_table.c:450
 task_work_run+0x24f/0x310 kernel/task_work.c:239
 exit_task_work include/linux/task_work.h:43 [inline]
 do_exit+0xa2f/0x28e0 kernel/exit.c:938
 do_group_exit+0x207/0x2c0 kernel/exit.c:1087
 get_signal+0x16b2/0x1750 kernel/signal.c:3016
 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
 syscall_exit_to_user_mode+0xce/0x340 kernel/entry/common.c:218
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

The buggy address belongs to the object at ffff88805b455000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1440 bytes inside of
 freed 2048-byte region [ffff88805b455000, ffff88805b455800)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5b450
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801ac42000 0000000000000000 dead000000000001
raw: 0000000000000000 0000000000080008 00000001f5000000 0000000000000000
head: 00fff00000000040 ffff88801ac42000 0000000000000000 dead000000000001
head: 0000000000000000 0000000000080008 00000001f5000000 0000000000000000
head: 00fff00000000003 ffffea00016d1401 ffffffffffffffff 0000000000000000
head: 0000000000000008 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6571, tgid 6571 (syz-executor), ts 94610591307, free_ts 94587680766
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1556
 prep_new_page mm/page_alloc.c:1564 [inline]
 get_page_from_freelist+0x3649/0x3790 mm/page_alloc.c:3474
 __alloc_pages_noprof+0x292/0x710 mm/page_alloc.c:4751
 alloc_pages_mpol_noprof+0x3e8/0x680 mm/mempolicy.c:2265
 alloc_slab_page+0x6a/0x140 mm/slub.c:2408
 allocate_slab+0x5a/0x2f0 mm/slub.c:2574
 new_slab mm/slub.c:2627 [inline]
 ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3815
 __slab_alloc+0x58/0xa0 mm/slub.c:3905
 __slab_alloc_node mm/slub.c:3980 [inline]
 slab_alloc_node mm/slub.c:4141 [inline]
 __do_kmalloc_node mm/slub.c:4282 [inline]
 __kmalloc_node_track_caller_noprof+0x2e9/0x4c0 mm/slub.c:4302
 kmalloc_reserve+0x111/0x2a0 net/core/skbuff.c:609
 pskb_expand_head+0x1f0/0x1380 net/core/skbuff.c:2275
 netlink_trim+0x183/0x220 net/netlink/af_netlink.c:1303
 netlink_broadcast_filtered+0x76/0x12a0 net/netlink/af_netlink.c:1509
 nlmsg_multicast_filtered include/net/netlink.h:1128 [inline]
 nlmsg_multicast include/net/netlink.h:1147 [inline]
 nlmsg_notify+0xfb/0x1c0 net/netlink/af_netlink.c:2585
 __dev_notify_flags+0xf7/0x400 net/core/dev.c:8978
 dev_change_flags+0xf0/0x1a0 net/core/dev.c:9020
page last free pid 6593 tgid 6593 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1127 [inline]
 free_unref_page+0xdf9/0x1140 mm/page_alloc.c:2657
 discard_slab mm/slub.c:2673 [inline]
 __put_partials+0xeb/0x130 mm/slub.c:3142
 put_cpu_partial+0x17c/0x250 mm/slub.c:3217
 __slab_free+0x2ea/0x3d0 mm/slub.c:4468
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4104 [inline]
 slab_alloc_node mm/slub.c:4153 [inline]
 kmem_cache_alloc_noprof+0x1d9/0x380 mm/slub.c:4160
 getname_flags+0xb7/0x540 fs/namei.c:139
 getname_maybe_null include/linux/fs.h:2796 [inline]
 vfs_fstatat+0x3f/0x130 fs/stat.c:361
 __do_sys_newfstatat fs/stat.c:530 [inline]
 __se_sys_newfstatat fs/stat.c:524 [inline]
 __x64_sys_newfstatat+0x11d/0x1a0 fs/stat.c:524
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88805b455480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805b455500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88805b455580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                               ^
 ffff88805b455600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805b455680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/12/04 05:07 net af8edaeddbc5 b50eb251 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce KASAN: slab-use-after-free Write in sco_conn_put
2024/12/03 09:33 net 3301ab7d5aeb 578925bc .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce KASAN: slab-use-after-free Write in sco_conn_put
2024/12/02 04:52 net a747e02430df 68914665 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce KASAN: slab-use-after-free Write in sco_conn_put
2024/11/29 19:53 net f1cd565ce577 68914665 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce KASAN: slab-use-after-free Write in sco_conn_put
2024/11/26 13:31 net 5d066766c5f1 11dbc254 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-this-kasan-gce KASAN: slab-use-after-free Write in sco_conn_put
* Struck through repros no longer work on HEAD.