syzbot


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

Status: upstream: reported C repro on 2024/09/18 16:26
Subsystems: mm
[Documentation on labels]
Reported-by: syzbot+6926ab9f6f7d7b50002e@syzkaller.appspotmail.com
First crash: 82d, last: 56d
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [mm?] KASAN: slab-use-after-free Read in shrinker_free 2 (3) 2024/09/18 22:55
Last patch testing requests (6)
Created Duration User Patch Repo Result
2024/10/24 12:13 19m retest repro upstream OK log
2024/10/24 10:21 22m retest repro upstream report log
2024/10/24 10:21 22m retest repro upstream OK log
2024/10/24 10:21 22m retest repro upstream OK log
2024/10/24 10:21 22m retest repro upstream OK log
2024/10/24 10:21 19m retest repro upstream OK log

Sample crash report:
svc: failed to register nfsdv3 RPC service (errno 512).
svc: failed to register nfsaclv3 RPC service (errno 512).
==================================================================
BUG: KASAN: slab-use-after-free in shrinker_free+0x3b7/0x430 mm/shrinker.c:775
Read of size 4 at addr ffff888022ab1e1c by task syz-executor209/5378

CPU: 1 UID: 0 PID: 5378 Comm: syz-executor209 Not tainted 6.11.0-rc7-syzkaller-00145-g57719771a244 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:93 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:119
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0xc3/0x620 mm/kasan/report.c:488
 kasan_report+0xd9/0x110 mm/kasan/report.c:601
 shrinker_free+0x3b7/0x430 mm/shrinker.c:775
 nfsd_file_cache_shutdown+0xbc/0x480 fs/nfsd/filecache.c:891
 nfsd_shutdown_generic fs/nfsd/nfssvc.c:329 [inline]
 nfsd_shutdown_generic fs/nfsd/nfssvc.c:323 [inline]
 nfsd_startup_net fs/nfsd/nfssvc.c:444 [inline]
 nfsd_svc+0x6d4/0x970 fs/nfsd/nfssvc.c:817
 nfsd_nl_threads_set_doit+0x52c/0xbc0 fs/nfsd/nfsctl.c:1714
 genl_family_rcv_msg_doit+0x202/0x2f0 net/netlink/genetlink.c:1115
 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
 genl_rcv_msg+0x565/0x800 net/netlink/genetlink.c:1210
 netlink_rcv_skb+0x165/0x410 net/netlink/af_netlink.c:2550
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline]
 netlink_unicast+0x53c/0x7f0 net/netlink/af_netlink.c:1357
 netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1901
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x9b4/0xb50 net/socket.c:2597
 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2651
 __sys_sendmsg+0x117/0x1f0 net/socket.c:2680
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f8e7a41daf9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 11 1d 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f8e7a36c158 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f8e7a4a0438 RCX: 00007f8e7a41daf9
RDX: 0000000000000004 RSI: 0000000020000280 RDI: 0000000000000003
RBP: 00007f8e7a4a0430 R08: 0000000000000008 R09: 0000000000000000
R10: 0000000000000003 R11: 0000000000000246 R12: 00007f8e7a4a043c
R13: 000000000000006e R14: 00007fffcd164cf0 R15: 00007fffcd164dd8
 </TASK>

Allocated by task 5370:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:370 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:387
 kmalloc_noprof include/linux/slab.h:681 [inline]
 kzalloc_noprof include/linux/slab.h:807 [inline]
 shrinker_alloc+0xf8/0xb00 mm/shrinker.c:683
 nfsd_file_cache_init+0x152/0x450 fs/nfsd/filecache.c:743
 nfsd_startup_generic fs/nfsd/nfssvc.c:307 [inline]
 nfsd_startup_net fs/nfsd/nfssvc.c:402 [inline]
 nfsd_svc+0x542/0x970 fs/nfsd/nfssvc.c:817
 nfsd_nl_threads_set_doit+0x52c/0xbc0 fs/nfsd/nfsctl.c:1714
 genl_family_rcv_msg_doit+0x202/0x2f0 net/netlink/genetlink.c:1115
 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
 genl_rcv_msg+0x565/0x800 net/netlink/genetlink.c:1210
 netlink_rcv_skb+0x165/0x410 net/netlink/af_netlink.c:2550
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline]
 netlink_unicast+0x53c/0x7f0 net/netlink/af_netlink.c:1357
 netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1901
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x9b4/0xb50 net/socket.c:2597
 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2651
 __sys_sendmsg+0x117/0x1f0 net/socket.c:2680
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 0:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:579
 poison_slab_object+0xf7/0x160 mm/kasan/common.c:240
 __kasan_slab_free+0x32/0x50 mm/kasan/common.c:256
 kasan_slab_free include/linux/kasan.h:184 [inline]
 slab_free_hook mm/slub.c:2256 [inline]
 slab_free mm/slub.c:4477 [inline]
 kfree+0x12a/0x3b0 mm/slub.c:4598
 rcu_do_batch kernel/rcu/tree.c:2569 [inline]
 rcu_core+0x828/0x16b0 kernel/rcu/tree.c:2843
 handle_softirqs+0x216/0x8f0 kernel/softirq.c:554
 __do_softirq kernel/softirq.c:588 [inline]
 invoke_softirq kernel/softirq.c:428 [inline]
 __irq_exit_rcu kernel/softirq.c:637 [inline]
 irq_exit_rcu+0xbb/0x120 kernel/softirq.c:649
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1043 [inline]
 sysvec_apic_timer_interrupt+0x95/0xb0 arch/x86/kernel/apic/apic.c:1043
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702

Last potentially related work creation:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 __kasan_record_aux_stack+0xba/0xd0 mm/kasan/generic.c:541
 __call_rcu_common.constprop.0+0x9a/0x790 kernel/rcu/tree.c:3106
 shrinker_free+0xfe/0x430 mm/shrinker.c:807
 nfsd_file_cache_shutdown+0xbc/0x480 fs/nfsd/filecache.c:891
 nfsd_shutdown_generic fs/nfsd/nfssvc.c:329 [inline]
 nfsd_shutdown_generic fs/nfsd/nfssvc.c:323 [inline]
 nfsd_startup_net fs/nfsd/nfssvc.c:444 [inline]
 nfsd_svc+0x6d4/0x970 fs/nfsd/nfssvc.c:817
 nfsd_nl_threads_set_doit+0x52c/0xbc0 fs/nfsd/nfsctl.c:1714
 genl_family_rcv_msg_doit+0x202/0x2f0 net/netlink/genetlink.c:1115
 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
 genl_rcv_msg+0x565/0x800 net/netlink/genetlink.c:1210
 netlink_rcv_skb+0x165/0x410 net/netlink/af_netlink.c:2550
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 netlink_unicast_kernel net/netlink/af_netlink.c:1331 [inline]
 netlink_unicast+0x53c/0x7f0 net/netlink/af_netlink.c:1357
 netlink_sendmsg+0x8b8/0xd70 net/netlink/af_netlink.c:1901
 sock_sendmsg_nosec net/socket.c:730 [inline]
 __sock_sendmsg net/socket.c:745 [inline]
 ____sys_sendmsg+0x9b4/0xb50 net/socket.c:2597
 ___sys_sendmsg+0x135/0x1e0 net/socket.c:2651
 __sys_sendmsg+0x117/0x1f0 net/socket.c:2680
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888022ab1e00
 which belongs to the cache kmalloc-192 of size 192
The buggy address is located 28 bytes inside of
 freed 192-byte region [ffff888022ab1e00, ffff888022ab1ec0)

The buggy address belongs to the physical page:
page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x22ab1
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xfdffffff(slab)
raw: 00fff00000000000 ffff88801ac413c0 ffffea000076d740 dead000000000004
raw: 0000000000000000 0000000000100010 00000001fdffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 1, tgid 1 (swapper/0), ts 4363825191, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x2d1/0x350 mm/page_alloc.c:1500
 prep_new_page mm/page_alloc.c:1508 [inline]
 get_page_from_freelist+0x1351/0x2e50 mm/page_alloc.c:3446
 __alloc_pages_noprof+0x22b/0x2460 mm/page_alloc.c:4702
 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline]
 alloc_pages_node_noprof include/linux/gfp.h:296 [inline]
 alloc_slab_page+0x4e/0xf0 mm/slub.c:2325
 allocate_slab mm/slub.c:2488 [inline]
 new_slab+0x84/0x260 mm/slub.c:2541
 ___slab_alloc+0xdac/0x1870 mm/slub.c:3727
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3817
 __slab_alloc_node mm/slub.c:3870 [inline]
 slab_alloc_node mm/slub.c:4029 [inline]
 __kmalloc_cache_noprof+0x2c5/0x310 mm/slub.c:4188
 kmalloc_noprof include/linux/slab.h:681 [inline]
 kzalloc_noprof include/linux/slab.h:807 [inline]
 call_usermodehelper_setup+0x9a/0x340 kernel/umh.c:363
 kobject_uevent_env+0xde3/0x1670 lib/kobject_uevent.c:628
 device_add+0x10e0/0x1a70 drivers/base/core.c:3663
 wakeup_source_device_create+0x214/0x2a0 drivers/base/power/wakeup_stats.c:161
 wakeup_source_sysfs_add+0x1c/0x90 drivers/base/power/wakeup_stats.c:181
 wakeup_source_register+0xaa/0x140 drivers/base/power/wakeup.c:223
 acpi_add_pm_notifier+0x12e/0x270 drivers/acpi/device_pm.c:589
 acpi_pci_root_add+0x45f/0xa90 drivers/acpi/pci_root.c:741
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888022ab1d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888022ab1d80: 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888022ab1e00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff888022ab1e80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff888022ab1f00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (17):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/09/14 19:24 upstream 57719771a244 08d8a733 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto KASAN: slab-use-after-free Read in shrinker_free
2024/10/10 10:20 upstream d3d1556696c1 a156c552 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto KASAN: slab-use-after-free Read in shrinker_free
2024/10/08 01:41 upstream 87d6aab2389e 402f1df0 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto KASAN: slab-use-after-free Read in shrinker_free
2024/10/06 23:17 upstream 2a130b7e1fcd d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto KASAN: slab-use-after-free Read in shrinker_free
2024/10/04 18:25 upstream 0c559323bbaa d7906eff .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto KASAN: slab-use-after-free Read in shrinker_free
2024/10/04 12:50 upstream 3840cbe24cf0 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto KASAN: slab-use-after-free Read in shrinker_free
2024/10/04 05:17 upstream 3840cbe24cf0 d7906eff .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto KASAN: slab-use-after-free Read in shrinker_free
2024/09/29 05:26 upstream 3efc57369a0c ba29ff75 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto KASAN: slab-use-after-free Read in shrinker_free
2024/09/28 09:01 upstream e477dba5442c 440b26ec .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto KASAN: slab-use-after-free Read in shrinker_free
2024/09/28 06:32 upstream e477dba5442c 440b26ec .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto KASAN: slab-use-after-free Read in shrinker_free
2024/09/20 23:01 upstream 176000734ee2 6f888b75 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto KASAN: slab-use-after-free Read in shrinker_free
2024/09/18 07:00 upstream a430d95c5efa c673ca06 .config console log report syz / log [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto KASAN: slab-use-after-free Read in shrinker_free
2024/09/17 22:35 upstream a430d95c5efa c673ca06 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto KASAN: slab-use-after-free Read in shrinker_free
2024/09/16 08:06 upstream a4ebad655b98 08d8a733 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto KASAN: slab-use-after-free Read in shrinker_free
2024/09/15 00:24 upstream 57719771a244 08d8a733 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto KASAN: slab-use-after-free Read in shrinker_free
2024/09/14 22:35 upstream 57719771a244 08d8a733 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto KASAN: slab-use-after-free Read in shrinker_free
2024/09/14 16:15 upstream 57719771a244 08d8a733 .config console log report info [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto KASAN: slab-use-after-free Read in shrinker_free
* Struck through repros no longer work on HEAD.