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KASAN: use-after-free Read in post_one_notification

Status: fixed on 2023/02/24 13:50
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+c70d87ac1d001f29a058@syzkaller.appspotmail.com
Fix commit: 353f7988dd84 watchqueue: make sure to serialize 'wqueue->defunct' properly
First crash: 982d, last: 779d
Cause bisection: the issue happens on the oldest tested release (bisect log)
Crash: KASAN: use-after-free Read in post_one_notification (log)
Repro: C syz .config
  
▶ ▼ Discussions (9)
Title Replies (including bot) Last reply
[PATCH v3] kernel/watch_queue: Make pipe NULL while clearing watch_queue 18 (18) 2022/08/04 08:39
Re: [syzbot] KASAN: use-after-free Read in post_one_notification 4 (4) 2022/08/03 05:17
[PATCH] kernel/watch_queue: Make pipe NULL while clearing watch_queue 18 (18) 2022/08/02 01:19
Re: [PATCH] kernel/watch_queue: Make pipe NULL while clearing watch_queue 2 (2) 2022/08/01 12:52
[syzbot] KASAN: use-after-free Read in post_one_notification 6 (11) 2022/07/28 15:50
Re: [PATCH v2] kernel/watch_queue: Make pipe NULL while clearing watch_queue 1 (1) 2022/07/27 14:49
Re: [PATCH v2] kernel/watch_queue: Make pipe NULL while clearing watch_queue 1 (1) 2022/07/24 07:48
Re: [PATCH v2] kernel/watch_queue: Make pipe NULL while clearing watch_queue 1 (1) 2022/07/24 06:26
[PATCH v2] kernel/watch_queue: Make pipe NULL while clearing watch_queue 1 (1) 2022/07/24 04:02
▶ ▼ Last patch testing requests (6)
Created Duration User Patch Repo Result
2022/08/01 10:35 17m hdanton@sina.com https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master OK log
2022/07/28 15:30 18m code@siddh.me https://github.com/siddhpant/linux.git post_one_notification OK log
2022/07/24 03:41 18m code@siddh.me https://github.com/siddhpant/linux.git post_one_notification OK log
2022/07/23 14:20 17m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 551acdc3c3d2 OK log
2022/07/23 13:23 18m code@siddh.me https://github.com/siddhpant/linux.git post_one_notification OK log
2022/07/23 13:20 0m code@siddh.me git@github.com:siddhpant/linux.git post_one_notification error
▶ ▼ Fix bisection attempts (1)
Created Duration User Patch Repo Result
2022/07/07 22:27 28m bisect fix upstream OK (0) job log log

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in __lock_acquire+0x3ab9/0x5660 kernel/locking/lockdep.c:4923
Read of size 8 at addr ffff88807846c4a8 by task syz-executor329/3909

CPU: 0 PID: 3909 Comm: syz-executor329 Not tainted 5.19.0-rc1-syzkaller-00003-ge71e60cd74df #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description.constprop.0.cold+0xeb/0x495 mm/kasan/report.c:313
 print_report mm/kasan/report.c:429 [inline]
 kasan_report.cold+0xf4/0x1c6 mm/kasan/report.c:491
 __lock_acquire+0x3ab9/0x5660 kernel/locking/lockdep.c:4923
 lock_acquire kernel/locking/lockdep.c:5665 [inline]
 lock_acquire+0x1ab/0x570 kernel/locking/lockdep.c:5630
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
 _raw_spin_lock_irq+0x32/0x50 kernel/locking/spinlock.c:170
 spin_lock_irq include/linux/spinlock.h:374 [inline]
 post_one_notification.isra.0+0x59/0x990 kernel/watch_queue.c:86
 __post_watch_notification kernel/watch_queue.c:206 [inline]
 __post_watch_notification+0x561/0x840 kernel/watch_queue.c:176
 post_watch_notification include/linux/watch_queue.h:109 [inline]
 notify_key security/keys/internal.h:199 [inline]
 __key_update security/keys/key.c:775 [inline]
 key_create_or_update+0xdbf/0xde0 security/keys/key.c:979
 __do_sys_add_key+0x215/0x430 security/keys/keyctl.c:134
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x46/0xb0
RIP: 0033:0x7f9ccf4c69f9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 15 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:00007f9ccf4782f8 EFLAGS: 00000246 ORIG_RAX: 00000000000000f8
RAX: ffffffffffffffda RBX: 00007f9ccf54e408 RCX: 00007f9ccf4c69f9
RDX: 00000000200000c0 RSI: 0000000020000080 RDI: 0000000020000040
RBP: 0000000000000000 R08: 00000000fffffffc R09: 0000000000000000
R10: 0000000000000048 R11: 0000000000000246 R12: 00007f9ccf54e400
R13: 00007f9ccf54e40c R14: 00007f9ccf51c064 R15: 3a74707972637366
 </TASK>

Allocated by task 3906:
 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:436 [inline]
 ____kasan_kmalloc mm/kasan/common.c:515 [inline]
 ____kasan_kmalloc mm/kasan/common.c:474 [inline]
 __kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:524
 kmalloc include/linux/slab.h:600 [inline]
 kzalloc include/linux/slab.h:733 [inline]
 alloc_pipe_info+0x105/0x590 fs/pipe.c:790
 get_pipe_inode fs/pipe.c:881 [inline]
 create_pipe_files+0x8d/0x880 fs/pipe.c:913
 __do_pipe_flags fs/pipe.c:962 [inline]
 do_pipe2+0x96/0x1b0 fs/pipe.c:1010
 __do_sys_pipe2 fs/pipe.c:1028 [inline]
 __se_sys_pipe2 fs/pipe.c:1026 [inline]
 __x64_sys_pipe2+0x50/0x70 fs/pipe.c:1026
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x46/0xb0

Freed by task 3907:
 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
 kasan_set_track+0x21/0x30 mm/kasan/common.c:45
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370
 ____kasan_slab_free mm/kasan/common.c:366 [inline]
 ____kasan_slab_free+0x166/0x1a0 mm/kasan/common.c:328
 kasan_slab_free include/linux/kasan.h:200 [inline]
 slab_free_hook mm/slub.c:1727 [inline]
 slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1753
 slab_free mm/slub.c:3507 [inline]
 kfree+0xd6/0x4d0 mm/slub.c:4555
 put_pipe_info fs/pipe.c:711 [inline]
 pipe_release+0x2b6/0x310 fs/pipe.c:734
 __fput+0x277/0x9d0 fs/file_table.c:317
 task_work_run+0xdd/0x1a0 kernel/task_work.c:177
 ptrace_notify+0x114/0x140 kernel/signal.c:2353
 ptrace_report_syscall include/linux/ptrace.h:420 [inline]
 ptrace_report_syscall_exit include/linux/ptrace.h:482 [inline]
 syscall_exit_work kernel/entry/common.c:249 [inline]
 syscall_exit_to_user_mode_prepare+0xdb/0x230 kernel/entry/common.c:276
 __syscall_exit_to_user_mode_work kernel/entry/common.c:281 [inline]
 syscall_exit_to_user_mode+0x9/0x50 kernel/entry/common.c:294
 do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x46/0xb0

The buggy address belongs to the object at ffff88807846c400
 which belongs to the cache kmalloc-cg-512 of size 512
The buggy address is located 168 bytes inside of
 512-byte region [ffff88807846c400, ffff88807846c600)

The buggy address belongs to the physical page:
page:ffffea0001e11b00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7846c
head:ffffea0001e11b00 order:2 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea0001f25a00 dead000000000002 ffff888011842dc0
raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3189, tgid 3189 (dhcpcd), ts 22292505782, free_ts 22224338092
 prep_new_page mm/page_alloc.c:2456 [inline]
 get_page_from_freelist+0x1290/0x3b70 mm/page_alloc.c:4198
 __alloc_pages+0x1c7/0x510 mm/page_alloc.c:5426
 alloc_pages+0x1aa/0x310 mm/mempolicy.c:2272
 alloc_slab_page mm/slub.c:1797 [inline]
 allocate_slab+0x26c/0x3c0 mm/slub.c:1942
 new_slab mm/slub.c:2002 [inline]
 ___slab_alloc+0x985/0xd90 mm/slub.c:3002
 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3089
 slab_alloc_node mm/slub.c:3180 [inline]
 slab_alloc mm/slub.c:3222 [inline]
 kmem_cache_alloc_trace+0x310/0x3f0 mm/slub.c:3253
 kmalloc include/linux/slab.h:600 [inline]
 kzalloc include/linux/slab.h:733 [inline]
 ipv6_add_addr+0x352/0x1f00 net/ipv6/addrconf.c:1099
 inet6_addr_add+0x412/0xae0 net/ipv6/addrconf.c:2973
 inet6_rtm_newaddr+0xfa4/0x1a60 net/ipv6/addrconf.c:4923
 rtnetlink_rcv_msg+0x43a/0xc90 net/core/rtnetlink.c:6089
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2501
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x543/0x7f0 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x917/0xe10 net/netlink/af_netlink.c:1921
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:734
 ____sys_sendmsg+0x6eb/0x810 net/socket.c:2492
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1371 [inline]
 free_pcp_prepare+0x549/0xd20 mm/page_alloc.c:1421
 free_unref_page_prepare mm/page_alloc.c:3343 [inline]
 free_unref_page+0x19/0x6a0 mm/page_alloc.c:3438
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:446
 kasan_slab_alloc include/linux/kasan.h:224 [inline]
 slab_post_alloc_hook mm/slab.h:750 [inline]
 slab_alloc_node mm/slub.c:3214 [inline]
 slab_alloc mm/slub.c:3222 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3229 [inline]
 kmem_cache_alloc+0x204/0x3b0 mm/slub.c:3239
 getname_flags.part.0+0x50/0x4f0 fs/namei.c:139
 getname_flags+0x9a/0xe0 include/linux/audit.h:323
 vfs_fstatat+0x73/0xb0 fs/stat.c:254
 __do_sys_newfstatat+0x91/0x110 fs/stat.c:425
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x46/0xb0

Memory state around the buggy address:
 ffff88807846c380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807846c400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88807846c480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff88807846c500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807846c580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (19):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/06/07 22:27 upstream e71e60cd74df c8857892 .config strace log report syz C ci-upstream-kasan-gce-root KASAN: use-after-free Read in post_one_notification
2022/03/18 09:25 upstream 551acdc3c3d2 e2d91b1d .config console log report syz C ci-upstream-kasan-gce KASAN: use-after-free Read in post_one_notification
2022/07/17 18:12 linux-next cb71b93c2dc3 95cb00d1 .config strace log report syz C ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in post_one_notification
2022/10/07 07:34 upstream ffb39098bf87 8a212197 .config console log report syz C [disk image] [vmlinux] ci-upstream-kasan-gce-selinux-root KASAN: stack-out-of-bounds Read in post_one_notification
2022/09/11 15:09 upstream b96fbd602d35 356d8217 .config console log report syz C [disk image] [vmlinux] ci-upstream-kasan-gce-smack-root KASAN: stack-out-of-bounds Read in post_one_notification
2022/07/10 09:08 upstream b1c428b6c368 b5765a15 .config console log report info ci-upstream-kasan-gce-smack-root KASAN: use-after-free Read in post_one_notification
2022/05/10 13:19 upstream 9be9ed2612b5 8b277b8e .config console log report info ci-upstream-kasan-gce-selinux-root KASAN: use-after-free Read in post_one_notification
2022/05/03 03:58 upstream 9050ba3a61a4 2df221f6 .config console log report info ci-upstream-kasan-gce-selinux-root KASAN: use-after-free Read in post_one_notification
2022/04/29 03:06 upstream 259b897e5a79 e9076525 .config console log report info ci-upstream-kasan-gce KASAN: use-after-free Read in post_one_notification
2022/04/27 03:27 upstream cf424ef014ac 1fa34c1b .config console log report info ci-upstream-kasan-gce-root KASAN: use-after-free Read in post_one_notification
2022/04/25 21:47 upstream d615b5416f8a 152baedd .config console log report info ci-upstream-kasan-gce KASAN: use-after-free Read in post_one_notification
2022/04/13 02:09 upstream a19944809fe9 dacb3f1c .config console log report info ci-qemu-upstream KASAN: use-after-free Read in post_one_notification
2022/04/04 08:46 upstream 09bb8856d4a7 79a2a8fc .config console log report info ci-upstream-kasan-gce-smack-root KASAN: use-after-free Read in post_one_notification
2022/03/21 16:59 upstream f443e374ae13 e2d91b1d .config console log report info ci-upstream-kasan-gce-root KASAN: use-after-free Read in post_one_notification
2022/03/20 00:10 upstream 97e9c8eb4bb1 e2d91b1d .config console log report info ci-upstream-kasan-gce KASAN: use-after-free Read in post_one_notification
2022/03/18 08:17 upstream 551acdc3c3d2 e2d91b1d .config console log report info ci-upstream-kasan-gce KASAN: use-after-free Read in post_one_notification
2022/03/17 13:18 upstream 56e337f2cf13 dfa9a8ed .config console log report info ci-upstream-kasan-gce-smack-root KASAN: use-after-free Read in post_one_notification
2022/04/10 05:47 upstream e1f700ebd6be e22c3da3 .config console log report info ci-qemu-upstream-386 KASAN: use-after-free Read in post_one_notification
2022/04/25 08:29 linux-next f1244c81da13 c889aef9 .config console log report info ci-upstream-linux-next-kasan-gce-root KASAN: use-after-free Read in post_one_notification
* Struck through repros no longer work on HEAD.