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KASAN: use-after-free Read in skb_queue_purge (2)

Status: upstream: reported on 2024/12/03 13:20
Reported-by: syzbot+40cbad34045cf6a80a4d@syzkaller.appspotmail.com
First crash: 124d, last: 20d
▶ ▼ Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 KASAN: use-after-free Read in skb_queue_purge 1 262d 262d 0/3 auto-obsoleted due to no activity on 2024/10/27 06:07

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in __lock_acquire+0x77/0x1f80 kernel/locking/lockdep.c:4919
Read of size 8 at addr ffff888028585888 by task syz.0.1206/8321

CPU: 1 PID: 8321 Comm: syz.0.1206 Not tainted 6.1.128-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:316 [inline]
 print_report+0x15f/0x4f0 mm/kasan/report.c:427
 kasan_report+0x136/0x160 mm/kasan/report.c:531
 __lock_acquire+0x77/0x1f80 kernel/locking/lockdep.c:4919
 lock_acquire+0x1f8/0x5a0 kernel/locking/lockdep.c:5662
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xd1/0x120 kernel/locking/spinlock.c:162
 skb_dequeue net/core/skbuff.c:3421 [inline]
 skb_queue_purge+0x2e/0x1c0 net/core/skbuff.c:3459
 vhci_flush+0x3b/0x40 drivers/bluetooth/hci_vhci.c:69
 hci_dev_do_reset net/bluetooth/hci_core.c:578 [inline]
 hci_dev_reset+0x418/0x5b0 net/bluetooth/hci_core.c:618
 sock_do_ioctl+0x152/0x450 net/socket.c:1204
 sock_ioctl+0x47f/0x770 net/socket.c:1321
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f75e3f8cde9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f75e4e4c038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f75e41a5fa0 RCX: 00007f75e3f8cde9
RDX: 0000000000000000 RSI: 00000000400448cb RDI: 0000000000000006
RBP: 00007f75e400e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f75e41a5fa0 R15: 00007ffcf9bf52a8
 </TASK>

Allocated by task 8119:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x97/0xb0 mm/kasan/common.c:383
 kmalloc include/linux/slab.h:563 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 vhci_open+0x53/0x360 drivers/bluetooth/hci_vhci.c:543
 misc_open+0x304/0x380 drivers/char/misc.c:143
 chrdev_open+0x54a/0x630 fs/char_dev.c:414
 do_dentry_open+0x7f9/0x10f0 fs/open.c:882
 do_open fs/namei.c:3626 [inline]
 path_openat+0x2644/0x2e60 fs/namei.c:3783
 do_filp_open+0x230/0x480 fs/namei.c:3810
 do_sys_openat2+0x13b/0x4f0 fs/open.c:1318
 do_sys_open fs/open.c:1334 [inline]
 __do_sys_openat fs/open.c:1350 [inline]
 __se_sys_openat fs/open.c:1345 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1345
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Freed by task 8119:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook mm/slub.c:1750 [inline]
 slab_free mm/slub.c:3661 [inline]
 __kmem_cache_free+0x25c/0x3c0 mm/slub.c:3674
 vhci_release+0xb6/0xd0 drivers/bluetooth/hci_vhci.c:579
 __fput+0x3f6/0x8d0 fs/file_table.c:320
 task_work_run+0x246/0x300 kernel/task_work.c:203
 exit_task_work include/linux/task_work.h:39 [inline]
 do_exit+0xa6e/0x26a0 kernel/exit.c:871
 do_group_exit+0x202/0x2b0 kernel/exit.c:1021
 __do_sys_exit_group kernel/exit.c:1032 [inline]
 __se_sys_exit_group kernel/exit.c:1030 [inline]
 __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1030
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Last potentially related work creation:
 kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:486
 call_rcu+0x163/0xa10 kernel/rcu/tree.c:2845
 qdisc_put net/sched/sch_generic.c:1104 [inline]
 dev_shutdown+0x359/0x440 net/sched/sch_generic.c:1492
 unregister_netdevice_many+0xaac/0x17a0 net/core/dev.c:10938
 default_device_exit_batch+0x956/0x9d0 net/core/dev.c:11460
 ops_exit_list net/core/net_namespace.c:177 [inline]
 cleanup_net+0x886/0xd20 net/core/net_namespace.c:640
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Second to last potentially related work creation:
 kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:486
 kvfree_call_rcu+0x116/0x8c0 kernel/rcu/tree.c:3401
 cgroup_migrate_finish+0x1b7/0x380 kernel/cgroup/cgroup.c:2731
 cgroup_attach_task+0x61e/0x970 kernel/cgroup/cgroup.c:2932
 __cgroup1_procs_write+0x2ef/0x460 kernel/cgroup/cgroup-v1.c:522
 cgroup_file_write+0x2c6/0x6c0 kernel/cgroup/cgroup.c:4081
 kernfs_fop_write_iter+0x3a2/0x4f0 fs/kernfs/file.c:334
 call_write_iter include/linux/fs.h:2265 [inline]
 new_sync_write fs/read_write.c:491 [inline]
 vfs_write+0x857/0xbc0 fs/read_write.c:584
 ksys_write+0x19c/0x2c0 fs/read_write.c:637
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

The buggy address belongs to the object at ffff888028585800
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 136 bytes inside of
 1024-byte region [ffff888028585800, ffff888028585c00)

The buggy address belongs to the physical page:
page:ffffea0000a16000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x28580
head:ffffea0000a16000 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888017c41dc0
raw: 0000000000000000 0000000000100010 00000001ffffffff 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 0x152a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL), pid 11, tgid 11 (kworker/u4:1), ts 78951703673, free_ts 78936031939
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2532
 prep_new_page mm/page_alloc.c:2539 [inline]
 get_page_from_freelist+0x3731/0x38d0 mm/page_alloc.c:4328
 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5605
 alloc_slab_page+0x6a/0x150 mm/slub.c:1794
 allocate_slab mm/slub.c:1939 [inline]
 new_slab+0x84/0x2d0 mm/slub.c:1992
 ___slab_alloc+0xc20/0x1270 mm/slub.c:3180
 __slab_alloc mm/slub.c:3279 [inline]
 slab_alloc_node mm/slub.c:3364 [inline]
 __kmem_cache_alloc_node+0x19f/0x260 mm/slub.c:3437
 __do_kmalloc_node mm/slab_common.c:935 [inline]
 __kmalloc+0xa1/0x230 mm/slab_common.c:949
 kmalloc include/linux/slab.h:568 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 ieee802_11_parse_elems_full+0xc4/0x1380 net/mac80211/util.c:1503
 ieee802_11_parse_elems_crc net/mac80211/ieee80211_i.h:2248 [inline]
 ieee802_11_parse_elems net/mac80211/ieee80211_i.h:2255 [inline]
 ieee80211_bss_info_update+0x99f/0xf00 net/mac80211/scan.c:212
 ieee80211_rx_bss_info net/mac80211/ibss.c:1120 [inline]
 ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1609 [inline]
 ieee80211_ibss_rx_queued_mgmt+0x1962/0x2dd0 net/mac80211/ibss.c:1638
 ieee80211_iface_process_skb net/mac80211/iface.c:1668 [inline]
 ieee80211_iface_work+0x7aa/0xce0 net/mac80211/iface.c:1722
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1459 [inline]
 free_pcp_prepare mm/page_alloc.c:1509 [inline]
 free_unref_page_prepare+0x12a6/0x15b0 mm/page_alloc.c:3384
 free_unref_page+0x33/0x3e0 mm/page_alloc.c:3479
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x156/0x170 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 __kmem_cache_alloc_node+0x137/0x260 mm/slub.c:3437
 kmalloc_trace+0x26/0xe0 mm/slab_common.c:1026
 kmalloc include/linux/slab.h:563 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 cfg80211_ibss_joined+0x180/0x560 net/wireless/ibss.c:73
 __ieee80211_sta_join_ibss+0xcd1/0x1530 net/mac80211/ibss.c:391
 ieee80211_sta_create_ibss+0x36a/0x610 net/mac80211/ibss.c:1348
 ieee80211_sta_find_ibss net/mac80211/ibss.c:1478 [inline]
 ieee80211_ibss_work+0xdde/0x1480 net/mac80211/ibss.c:1705
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Memory state around the buggy address:
 ffff888028585780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888028585800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888028585880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff888028585900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888028585980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (4):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/02/06 01:45 linux-6.1.y 0cbb5f65e52f 4dc70884 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in skb_queue_purge
2024/12/03 13:20 linux-6.1.y e4d90d63d385 578925bc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in skb_queue_purge
2025/03/17 18:59 linux-6.1.y 344a09659766 948c34e4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in skb_queue_purge
2025/03/17 18:55 linux-6.1.y 344a09659766 948c34e4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in skb_queue_purge
* Struck through repros no longer work on HEAD.