syzbot


KASAN: slab-use-after-free Read in lockref_get

Status: upstream: reported C repro on 2024/07/16 02:02
Subsystems: wireless fs
[Documentation on labels]
Reported-by: syzbot+d5dc2801166df6d34774@syzkaller.appspotmail.com
First crash: 179d, last: 42d
Cause bisection: introduced by (bisect log) :
commit 0a3d898ee9a8303d5b3982b97ef0703919c3ea76
Author: Benjamin Berg <benjamin.berg@intel.com>
Date: Wed Dec 20 02:38:01 2023 +0000

  wifi: mac80211: add/remove driver debugfs entries as appropriate

Crash: KASAN: slab-use-after-free Read in lockref_get (log)
Repro: C syz .config
  
Discussions (3)
Title Replies (including bot) Last reply
Managing debugfs entries and https://syzkaller.appspot.com/bug?extid=d5dc2801166df6d34774 2 (2) 2024/07/19 09:38
[syzbot] [fs?] KASAN: slab-use-after-free Read in lockref_get 8 (17) 2024/07/18 14:18
[PATCH] wifi: wireless: fix more UBSAN noise in cfg80211_conn_scan() 2 (2) 2024/07/16 18:21
Last patch testing requests (13)
Created Duration User Patch Repo Result
2024/10/22 07:32 46m retest repro net-next report log
2024/10/22 07:32 21m retest repro net-next report log
2024/10/08 06:51 21m retest repro net-next report log
2024/07/30 06:28 26m retest repro net-next report log
2024/07/30 06:28 19m retest repro net-next report log
2024/07/30 06:28 18m retest repro net-next report log
2024/07/18 10:40 1h35m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git 58f9416d413a OK log
2024/07/17 14:07 1h37m eadavis@qq.com patch git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git 58f9416d413a OK log
2024/07/17 13:19 18m eadavis@qq.com patch git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git 58f9416d413a report log
2024/07/17 11:39 1h09m eadavis@qq.com patch git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git 58f9416d413a report log
2024/07/17 10:59 17m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git 58f9416d413a report log
2024/07/17 03:24 21m eadavis@qq.com patch git://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git 58f9416d413a report log
2024/07/16 11:20 1h13m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next.git 58f9416d413a report log

Sample crash report:
wlan1: authentication with 08:02:11:00:00:00 timed out
==================================================================
BUG: KASAN: slab-use-after-free in __lock_acquire+0x78/0x1fd0 kernel/locking/lockdep.c:5005
Read of size 8 at addr ffff88807d6a4c70 by task kworker/u8:0/11

CPU: 1 PID: 11 Comm: kworker/u8:0 Not tainted 6.10.0-rc6-syzkaller-01414-g58f9416d413a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Workqueue: events_unbound cfg80211_wiphy_work
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
 __lock_acquire+0x78/0x1fd0 kernel/locking/lockdep.c:5005
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5754
 __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
 _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
 spin_lock include/linux/spinlock.h:351 [inline]
 lockref_get+0x15/0x60 lib/lockref.c:50
 dget include/linux/dcache.h:333 [inline]
 simple_recursive_removal+0x35/0x8e0 fs/libfs.c:601
 debugfs_remove+0x49/0x70 fs/debugfs/inode.c:823
 ieee80211_sta_debugfs_remove+0x40/0x60 net/mac80211/debugfs_sta.c:1287
 __sta_info_destroy_part2+0x35e/0x450 net/mac80211/sta_info.c:1476
 __sta_info_destroy net/mac80211/sta_info.c:1492 [inline]
 sta_info_destroy_addr+0xf4/0x140 net/mac80211/sta_info.c:1504
 ieee80211_destroy_auth_data+0x139/0x270 net/mac80211/mlme.c:4163
 ieee80211_sta_work+0x1256/0x3850 net/mac80211/mlme.c:7801
 cfg80211_wiphy_work+0x2db/0x490 net/wireless/core.c:440
 process_one_work kernel/workqueue.c:3248 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3329
 worker_thread+0x86d/0xd50 kernel/workqueue.c:3409
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Allocated by task 5098:
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_save_track+0x3f/0x80 mm/kasan/common.c:68
 unpoison_slab_object mm/kasan/common.c:312 [inline]
 __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook mm/slub.c:3940 [inline]
 slab_alloc_node mm/slub.c:4002 [inline]
 kmem_cache_alloc_lru_noprof+0x139/0x2b0 mm/slub.c:4021
 __d_alloc+0x31/0x700 fs/dcache.c:1624
 d_alloc fs/dcache.c:1704 [inline]
 d_alloc_parallel+0xdf/0x1600 fs/dcache.c:2462
 __lookup_slow+0x117/0x3f0 fs/namei.c:1677
 lookup_one_len+0x18b/0x2d0 fs/namei.c:2764
 start_creating+0x187/0x310 fs/debugfs/inode.c:378
 debugfs_create_dir+0x25/0x430 fs/debugfs/inode.c:593
 ieee80211_sta_debugfs_add+0x132/0x820 net/mac80211/debugfs_sta.c:1262
 sta_info_insert_finish net/mac80211/sta_info.c:881 [inline]
 sta_info_insert_rcu+0xecf/0x1900 net/mac80211/sta_info.c:949
 sta_info_insert+0x16/0xc0 net/mac80211/sta_info.c:954
 ieee80211_prep_connection+0xecd/0x12d0 net/mac80211/mlme.c:8319
 ieee80211_mgd_auth+0xd42/0x14c0 net/mac80211/mlme.c:8564
 rdev_auth net/wireless/rdev-ops.h:485 [inline]
 cfg80211_mlme_auth+0x59f/0x980 net/wireless/mlme.c:291
 cfg80211_conn_do_work+0x5ed/0xe60 net/wireless/sme.c:181
 cfg80211_conn_work+0x27c/0x4d0 net/wireless/sme.c:271
 process_one_work kernel/workqueue.c:3248 [inline]
 process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3329
 worker_thread+0x86d/0xd50 kernel/workqueue.c:3409
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Freed by task 24:
 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:579
 poison_slab_object+0xe0/0x150 mm/kasan/common.c:240
 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2196 [inline]
 slab_free mm/slub.c:4438 [inline]
 kmem_cache_free+0x145/0x350 mm/slub.c:4513
 rcu_do_batch kernel/rcu/tree.c:2535 [inline]
 rcu_core+0xafd/0x1830 kernel/rcu/tree.c:2809
 handle_softirqs+0x2c4/0x970 kernel/softirq.c:554
 run_ksoftirqd+0xca/0x130 kernel/softirq.c:928
 smpboot_thread_fn+0x544/0xa30 kernel/smpboot.c:164
 kthread+0x2f0/0x390 kernel/kthread.c:389
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Last potentially related work creation:
 kasan_save_stack+0x3f/0x60 mm/kasan/common.c:47
 __kasan_record_aux_stack+0xac/0xc0 mm/kasan/generic.c:541
 __call_rcu_common kernel/rcu/tree.c:3072 [inline]
 call_rcu+0x167/0xa70 kernel/rcu/tree.c:3176
 __dentry_kill+0x497/0x630 fs/dcache.c:622
 dput+0x19f/0x2b0 fs/dcache.c:845
 find_next_child fs/libfs.c:594 [inline]
 simple_recursive_removal+0x2bd/0x8e0 fs/libfs.c:609
 debugfs_remove+0x49/0x70 fs/debugfs/inode.c:823
 ieee80211_debugfs_remove_netdev net/mac80211/debugfs_netdev.c:1022 [inline]
 ieee80211_debugfs_recreate_netdev+0xc4/0x1400 net/mac80211/debugfs_netdev.c:1044
 drv_remove_interface+0x1e1/0x590 net/mac80211/driver-ops.c:119
 _ieee80211_change_mac net/mac80211/iface.c:278 [inline]
 ieee80211_change_mac+0xaf5/0x11e0 net/mac80211/iface.c:310
 dev_set_mac_address+0x327/0x510 net/core/dev.c:9095
 dev_set_mac_address_user+0x31/0x50 net/core/dev.c:9114
 dev_ifsioc+0xbd9/0xe70 net/core/dev_ioctl.c:541
 dev_ioctl+0x719/0x1340 net/core/dev_ioctl.c:786
 sock_do_ioctl+0x240/0x460 net/socket.c:1236
 sock_ioctl+0x629/0x8e0 net/socket.c:1341
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:907 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:893
 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

The buggy address belongs to the object at ffff88807d6a4bc0
 which belongs to the cache dentry of size 312
The buggy address is located 176 bytes inside of
 freed 312-byte region [ffff88807d6a4bc0, ffff88807d6a4cf8)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7d6a4
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffefff(slab)
raw: 00fff00000000040 ffff888015ef98c0 ffffea0000938380 dead000000000002
raw: 0000000000000000 0000000000150015 00000001ffffefff 0000000000000000
head: 00fff00000000040 ffff888015ef98c0 ffffea0000938380 dead000000000002
head: 0000000000000000 0000000000150015 00000001ffffefff 0000000000000000
head: 00fff00000000001 ffffea0001f5a901 ffffffffffffffff 0000000000000000
head: 0000000000000002 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Reclaimable, gfp_mask 0xd20d0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_RECLAIMABLE), pid 4546, tgid 4546 (udevd), ts 31019933045, free_ts 16115168775
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1473
 prep_new_page mm/page_alloc.c:1481 [inline]
 get_page_from_freelist+0x2e4c/0x2f10 mm/page_alloc.c:3425
 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4683
 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:296 [inline]
 alloc_slab_page+0x5f/0x120 mm/slub.c:2265
 allocate_slab+0x5a/0x2f0 mm/slub.c:2428
 new_slab mm/slub.c:2481 [inline]
 ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3667
 __slab_alloc+0x58/0xa0 mm/slub.c:3757
 __slab_alloc_node mm/slub.c:3810 [inline]
 slab_alloc_node mm/slub.c:3990 [inline]
 kmem_cache_alloc_lru_noprof+0x1c5/0x2b0 mm/slub.c:4021
 __d_alloc+0x31/0x700 fs/dcache.c:1624
 d_alloc fs/dcache.c:1704 [inline]
 d_alloc_parallel+0xdf/0x1600 fs/dcache.c:2462
 lookup_open fs/namei.c:3430 [inline]
 open_last_lookups fs/namei.c:3574 [inline]
 path_openat+0x92f/0x35f0 fs/namei.c:3810
 do_filp_open+0x235/0x490 fs/namei.c:3840
 do_sys_openat2+0x13e/0x1d0 fs/open.c:1413
 do_sys_open fs/open.c:1428 [inline]
 __do_sys_openat fs/open.c:1444 [inline]
 __se_sys_openat fs/open.c:1439 [inline]
 __x64_sys_openat+0x247/0x2a0 fs/open.c:1439
 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
page last free pid 1 tgid 1 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1093 [inline]
 free_unref_page+0xd22/0xea0 mm/page_alloc.c:2588
 free_contig_range+0x9e/0x160 mm/page_alloc.c:6642
 destroy_args+0x8a/0x890 mm/debug_vm_pgtable.c:1017
 debug_vm_pgtable+0x4be/0x550 mm/debug_vm_pgtable.c:1397
 do_one_initcall+0x248/0x880 init/main.c:1267
 do_initcall_level+0x157/0x210 init/main.c:1329
 do_initcalls+0x3f/0x80 init/main.c:1345
 kernel_init_freeable+0x435/0x5d0 init/main.c:1578
 kernel_init+0x1d/0x2b0 init/main.c:1467
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

Memory state around the buggy address:
 ffff88807d6a4b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88807d6a4b80: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
>ffff88807d6a4c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                             ^
 ffff88807d6a4c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc
 ffff88807d6a4d00: fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 00
==================================================================

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/07/16 06:16 net-next 58f9416d413a e8709b21 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-upstream-net-next-test-gce KASAN: slab-use-after-free Read in lockref_get
2024/07/16 04:14 net-next 58f9416d413a e8709b21 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-upstream-net-next-test-gce KASAN: slab-use-after-free Read in lockref_get
2024/07/16 02:01 net-next 58f9416d413a e8709b21 .config strace log report syz / log C [disk image] [vmlinux] [kernel image] ci2-upstream-net-next-test-gce KASAN: slab-use-after-free Read in lockref_get
2024/06/07 02:07 net-next 749332814479 121701b6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-net-next-test-gce KASAN: slab-use-after-free Read in lockref_get
2024/06/07 02:07 net-next 749332814479 121701b6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-net-next-test-gce KASAN: slab-use-after-free Read in lockref_get
* Struck through repros no longer work on HEAD.