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

Status: auto-obsoleted due to no activity on 2024/12/27 00:19
Reported-by: syzbot+22d395c2aaefa4e3993b@syzkaller.appspotmail.com
First crash: 126d, last: 126d
▶ ▼ Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: use-after-free Read in tty_write_room serial 12 871d 1128d 0/28 auto-obsoleted due to no activity on 2023/01/01 23:03
linux-6.1 KASAN: use-after-free Read in tty_write_room 1 49d 49d 0/3 upstream: reported on 2024/12/03 11:12
linux-5.15 KASAN: use-after-free Read in tty_write_room 1 460d 460d 0/3 auto-obsoleted due to no activity on 2024/01/27 09:51
upstream BUG: unable to handle kernel NULL pointer dereference in tty_write_room serial syz error 6 574d 631d 0/28 auto-obsoleted due to no activity on 2023/10/05 13:52
upstream KASAN: slab-use-after-free Read in tty_write_room (2) serial syz error error 88 19h03m 371d 0/28 upstream: reported syz repro on 2024/01/16 15:06
upstream KASAN: slab-use-after-free Read in tty_write_room serial 1 472d 468d 0/28 auto-obsoleted due to no activity on 2024/01/09 18:18

Sample crash report:
ieee802154 phy0 wpan0: encryption failed: -22
ieee802154 phy1 wpan1: encryption failed: -22
==================================================================
BUG: KASAN: use-after-free in tty_write_room+0x31/0x80 drivers/tty/tty_ioctl.c:78
Read of size 8 at addr ffff888022392018 by task aoe_tx0/1389

CPU: 0 PID: 1389 Comm: aoe_tx0 Not tainted 5.15.167-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2d0 lib/dump_stack.c:106
 print_address_description+0x63/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0x16b/0x1c0 mm/kasan/report.c:451
 tty_write_room+0x31/0x80 drivers/tty/tty_ioctl.c:78
 handle_tx+0x164/0x620 drivers/net/caif/caif_serial.c:226
 __netdev_start_xmit include/linux/netdevice.h:5019 [inline]
 netdev_start_xmit include/linux/netdevice.h:5033 [inline]
 xmit_one net/core/dev.c:3617 [inline]
 dev_hard_start_xmit+0x298/0x7a0 net/core/dev.c:3633
 __dev_queue_xmit+0x1cee/0x3230 net/core/dev.c:4248
 tx+0x65/0x160 drivers/block/aoe/aoenet.c:63
 kthread+0x234/0x440 drivers/block/aoe/aoecmd.c:1230
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Allocated by task 22220:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 ____kasan_kmalloc+0xba/0xf0 mm/kasan/common.c:513
 kasan_kmalloc include/linux/kasan.h:264 [inline]
 kmem_cache_alloc_trace+0x143/0x290 mm/slub.c:3247
 kmalloc include/linux/slab.h:591 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 alloc_tty_struct+0xa5/0x7b0 drivers/tty/tty_io.c:3127
 tty_init_dev+0x56/0x4b0 drivers/tty/tty_io.c:1424
 tty_open_by_driver drivers/tty/tty_io.c:2100 [inline]
 tty_open+0x9e1/0xde0 drivers/tty/tty_io.c:2148
 chrdev_open+0x54a/0x630 fs/char_dev.c:414
 do_dentry_open+0x807/0xfb0 fs/open.c:826
 do_open fs/namei.c:3608 [inline]
 path_openat+0x2705/0x2f20 fs/namei.c:3742
 do_filp_open+0x21c/0x460 fs/namei.c:3769
 do_sys_openat2+0x13b/0x4f0 fs/open.c:1253
 do_sys_open fs/open.c:1269 [inline]
 __do_sys_openat fs/open.c:1285 [inline]
 __se_sys_openat fs/open.c:1280 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1280
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Freed by task 14845:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4b/0x80 mm/kasan/common.c:46
 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
 ____kasan_slab_free+0xd8/0x120 mm/kasan/common.c:366
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1705 [inline]
 slab_free_freelist_hook+0xdd/0x160 mm/slub.c:1731
 slab_free mm/slub.c:3499 [inline]
 kfree+0xf1/0x270 mm/slub.c:4559
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

Last potentially related work creation:
 kasan_save_stack+0x36/0x60 mm/kasan/common.c:38
 kasan_record_aux_stack+0xba/0x100 mm/kasan/generic.c:348
 insert_work+0x54/0x3e0 kernel/workqueue.c:1366
 __queue_work+0x963/0xd00 kernel/workqueue.c:1532
 queue_work_on+0x14b/0x250 kernel/workqueue.c:1559
 tty_release_struct+0xb8/0xd0 drivers/tty/tty_io.c:1719
 tty_release+0xd53/0x1310 drivers/tty/tty_io.c:1880
 __fput+0x3fe/0x8e0 fs/file_table.c:280
 task_work_run+0x129/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x106/0x130 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x5d/0x240 kernel/entry/common.c:307
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Second to last potentially related work creation:
 kasan_save_stack+0x36/0x60 mm/kasan/common.c:38
 kasan_record_aux_stack+0xba/0x100 mm/kasan/generic.c:348
 kvfree_call_rcu+0x118/0x8a0 kernel/rcu/tree.c:3596
 drop_sysctl_table+0x317/0x460 fs/proc/proc_sysctl.c:1678
 unregister_sysctl_table+0x88/0x130 fs/proc/proc_sysctl.c:1716
 __devinet_sysctl_unregister net/ipv4/devinet.c:2613 [inline]
 devinet_sysctl_unregister net/ipv4/devinet.c:2641 [inline]
 inetdev_destroy net/ipv4/devinet.c:324 [inline]
 inetdev_event+0x7ba/0x1490 net/ipv4/devinet.c:1598
 notifier_call_chain kernel/notifier.c:83 [inline]
 raw_notifier_call_chain+0xd0/0x170 kernel/notifier.c:391
 call_netdevice_notifiers_info net/core/dev.c:2018 [inline]
 call_netdevice_notifiers_extack net/core/dev.c:2030 [inline]
 call_netdevice_notifiers net/core/dev.c:2044 [inline]
 unregister_netdevice_many+0xf1b/0x18f0 net/core/dev.c:11094
 ip6gre_exit_batch_net+0x415/0x460 net/ipv6/ip6_gre.c:1650
 ops_exit_list net/core/net_namespace.c:177 [inline]
 cleanup_net+0x763/0xb60 net/core/net_namespace.c:599
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

The buggy address belongs to the object at ffff888022392000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 24 bytes inside of
 2048-byte region [ffff888022392000, ffff888022392800)
The buggy address belongs to the page:
page:ffffea000088e400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x22390
head:ffffea000088e400 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888017042000
raw: 0000000000000000 0000000000080008 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 408, ts 8812539865, free_ts 0
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x322a/0x33c0 mm/page_alloc.c:4159
 __alloc_pages+0x272/0x700 mm/page_alloc.c:5423
 alloc_slab_page mm/slub.c:1775 [inline]
 allocate_slab mm/slub.c:1912 [inline]
 new_slab+0xbb/0x4b0 mm/slub.c:1975
 ___slab_alloc+0x6f6/0xe10 mm/slub.c:3008
 __slab_alloc mm/slub.c:3095 [inline]
 slab_alloc_node mm/slub.c:3186 [inline]
 slab_alloc mm/slub.c:3228 [inline]
 __kmalloc+0x1c9/0x300 mm/slub.c:4403
 kmalloc include/linux/slab.h:596 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 scsi_alloc_target+0x136/0xbb0 drivers/scsi/scsi_scan.c:489
 __scsi_scan_target+0x174/0x10b0 drivers/scsi/scsi_scan.c:1621
 scsi_scan_channel drivers/scsi/scsi_scan.c:1726 [inline]
 scsi_scan_host_selected+0x37a/0x690 drivers/scsi/scsi_scan.c:1755
 do_scsi_scan_host drivers/scsi/scsi_scan.c:1894 [inline]
 do_scan_async+0x12e/0x780 drivers/scsi/scsi_scan.c:1904
 async_run_entry_fn+0xa2/0x410 kernel/async.c:127
 process_one_work+0x8a1/0x10c0 kernel/workqueue.c:2310
 worker_thread+0xaca/0x1280 kernel/workqueue.c:2457
 kthread+0x3f6/0x4f0 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888022391f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888022391f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888022392000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff888022392080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888022392100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/09/18 00:19 linux-5.15.y 3a5928702e71 c673ca06 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in tty_write_room
* Struck through repros no longer work on HEAD.