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KCSAN: data-race in __d_rehash / retain_dentry (4)

Status: auto-obsoleted due to no activity on 2023/09/29 23:13
Subsystems: fs
[Documentation on labels]
First crash: 264d, last: 246d
Similar bugs (4)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __d_rehash / retain_dentry fs 1 1093d 1093d 0/26 auto-closed as invalid on 2021/06/05 04:33
upstream KCSAN: data-race in __d_rehash / retain_dentry (2) fs 1 690d 689d 0/26 auto-closed as invalid on 2022/07/12 06:48
upstream KCSAN: data-race in __d_rehash / retain_dentry (3) fs 1 341d 341d 0/26 auto-obsoleted due to no activity on 2023/06/26 14:48
upstream KCSAN: data-race in __d_rehash / retain_dentry (5) ext4 1 131d 131d 0/26 auto-obsoleted due to no activity on 2024/01/23 04:25

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __d_rehash / retain_dentry

write to 0xffff8881027ae490 of 8 bytes by task 3082 on cpu 1:
 hlist_bl_add_head_rcu include/linux/rculist_bl.h:81 [inline]
 __d_rehash+0xc4/0x220 fs/dcache.c:2579
 __d_add+0x36d/0x4a0 fs/dcache.c:2794
 d_splice_alias+0xd6/0x270 fs/dcache.c:3182
 proc_sys_lookup+0x3a7/0x460 fs/proc/proc_sysctl.c:542
 lookup_open fs/namei.c:3470 [inline]
 open_last_lookups fs/namei.c:3560 [inline]
 path_openat+0xc4f/0x1d10 fs/namei.c:3790
 do_filp_open+0xf6/0x200 fs/namei.c:3820
 do_sys_openat2+0xab/0x110 fs/open.c:1407
 do_sys_open fs/open.c:1422 [inline]
 __do_sys_openat fs/open.c:1438 [inline]
 __se_sys_openat fs/open.c:1433 [inline]
 __x64_sys_openat+0xf3/0x120 fs/open.c:1433
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff8881027ae490 of 8 bytes by task 3081 on cpu 0:
 hlist_bl_unhashed include/linux/list_bl.h:54 [inline]
 d_unhashed include/linux/dcache.h:335 [inline]
 retain_dentry+0x40/0x190 fs/dcache.c:668
 dput+0x108/0x1f0 fs/dcache.c:908
 __fput+0x46f/0x600 fs/file_table.c:392
 ____fput+0x15/0x20 fs/file_table.c:412
 task_work_run+0x135/0x1a0 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xd1/0xe0 kernel/entry/common.c:171
 exit_to_user_mode_prepare+0x6c/0xb0 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x26/0x140 kernel/entry/common.c:297
 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0xffff888237ac4ca8 -> 0xffff888106155908

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 3081 Comm: syz-executor.5 Not tainted 6.5.0-rc7-syzkaller-00164-g382d4cd18475 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/26/2023
==================================================================
chnl_net:caif_netlink_parms(): no params data found
bridge0: port 1(bridge_slave_0) entered blocking state
bridge0: port 1(bridge_slave_0) entered disabled state
bridge_slave_0: entered allmulticast mode
bridge_slave_0: entered promiscuous mode
bridge0: port 2(bridge_slave_1) entered blocking state
bridge0: port 2(bridge_slave_1) entered disabled state
bridge_slave_1: entered allmulticast mode
bridge_slave_1: entered promiscuous mode
bond0: (slave bond_slave_0): Enslaving as an active interface with an up link
bond0: (slave bond_slave_1): Enslaving as an active interface with an up link
team0: Port device team_slave_0 added
team0: Port device team_slave_1 added
batman_adv: batadv0: Adding interface: batadv_slave_0
batman_adv: batadv0: The MTU of interface batadv_slave_0 is too small (1500) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would solve the problem.
batman_adv: batadv0: Not using interface batadv_slave_0 (retrying later): interface not active
batman_adv: batadv0: Adding interface: batadv_slave_1
batman_adv: batadv0: The MTU of interface batadv_slave_1 is too small (1500) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would solve the problem.
batman_adv: batadv0: Not using interface batadv_slave_1 (retrying later): interface not active
hsr_slave_0: entered promiscuous mode
hsr_slave_1: entered promiscuous mode
debugfs: Directory 'hsr0' with parent 'hsr' already present!
Cannot create hsr debugfs directory
netdevsim netdevsim5 netdevsim0: renamed from eth0
netdevsim netdevsim5 netdevsim1: renamed from eth1
netdevsim netdevsim5 netdevsim2: renamed from eth2
netdevsim netdevsim5 netdevsim3: renamed from eth3
8021q: adding VLAN 0 to HW filter on device bond0
8021q: adding VLAN 0 to HW filter on device team0
8021q: adding VLAN 0 to HW filter on device batadv0
veth0_vlan: entered promiscuous mode
veth1_vlan: entered promiscuous mode
veth0_macvtap: entered promiscuous mode
veth1_macvtap: entered promiscuous mode
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_0
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_0
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_0
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_0
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3e) already exists on: batadv_slave_0
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
batman_adv: batadv0: Interface activated: batadv_slave_0
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3f) already exists on: batadv_slave_1
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3f) already exists on: batadv_slave_1
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3f) already exists on: batadv_slave_1
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3f) already exists on: batadv_slave_1
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
batman_adv: The newly added mac address (aa:aa:aa:aa:aa:3f) already exists on: batadv_slave_1
batman_adv: It is strongly recommended to keep mac addresses unique to avoid problems!
batman_adv: batadv0: Interface activated: batadv_slave_1
netdevsim netdevsim5 netdevsim0: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim5 netdevsim1: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim5 netdevsim2: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim5 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2023/08/25 23:04 upstream 382d4cd18475 03d9c195 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __d_rehash / retain_dentry
2023/08/07 18:31 upstream a027b2eca0b7 b1b6ae3d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __d_rehash / retain_dentry
* Struck through repros no longer work on HEAD.