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KCSAN: data-race in __d_lookup / __d_rehash (3)

Status: auto-obsoleted due to no activity on 2022/12/14 23:50
Subsystems: fs
[Documentation on labels]
First crash: 693d, last: 693d
Similar bugs (7)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __d_lookup / __d_rehash (8) ext4 8 49d 166d 0/28 auto-obsoleted due to no activity on 2024/09/19 14:50
upstream KCSAN: data-race in __d_lookup / __d_rehash (6) fs 1 404d 404d 0/28 auto-obsoleted due to no activity on 2023/09/29 22:29
upstream KCSAN: data-race in __d_lookup / __d_rehash (4) ext4 1 522d 522d 0/28 auto-obsoleted due to no activity on 2023/06/04 03:50
upstream KCSAN: data-race in __d_lookup / __d_rehash fs 1 1784d 1784d 0/28 auto-closed as invalid on 2020/01/24 17:56
upstream KCSAN: data-race in __d_lookup / __d_rehash (2) fs 1 887d 887d 0/28 auto-closed as invalid on 2022/06/04 08:25
upstream KCSAN: data-race in __d_lookup / __d_rehash (5) ext4 2 463d 464d 0/28 auto-obsoleted due to no activity on 2023/08/02 16:55
upstream KCSAN: data-race in __d_lookup / __d_rehash (7) ext4 1 358d 358d 0/28 auto-obsoleted due to no activity on 2023/11/15 16:47

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

write to 0xffff88810ac18c10 of 8 bytes by task 1832 on cpu 1:
 hlist_bl_add_head_rcu include/linux/rculist_bl.h:81 [inline]
 __d_rehash+0xb9/0x1f0 fs/dcache.c:2579
 __d_add+0x36d/0x4a0 fs/dcache.c:2794
 d_splice_alias+0xd5/0x310 fs/dcache.c:3182
 proc_sys_lookup+0x3bc/0x470 fs/proc/proc_sysctl.c:548
 lookup_open fs/namei.c:3391 [inline]
 open_last_lookups fs/namei.c:3481 [inline]
 path_openat+0xb1c/0x1b00 fs/namei.c:3710
 do_filp_open+0x105/0x220 fs/namei.c:3740
 do_sys_openat2+0xb5/0x2a0 fs/open.c:1310
 do_sys_open fs/open.c:1326 [inline]
 __do_sys_openat fs/open.c:1342 [inline]
 __se_sys_openat fs/open.c:1337 [inline]
 __x64_sys_openat+0xef/0x110 fs/open.c:1337
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88810ac18c10 of 8 bytes by task 1826 on cpu 0:
 hlist_bl_unhashed include/linux/list_bl.h:54 [inline]
 d_unhashed include/linux/dcache.h:335 [inline]
 __d_lookup+0x14d/0x3d0 fs/dcache.c:2491
 lookup_fast+0x4b/0x270 fs/namei.c:1643
 open_last_lookups fs/namei.c:3450 [inline]
 path_openat+0x457/0x1b00 fs/namei.c:3710
 do_filp_open+0x105/0x220 fs/namei.c:3740
 do_sys_openat2+0xb5/0x2a0 fs/open.c:1310
 do_sys_open fs/open.c:1326 [inline]
 __do_sys_openat fs/open.c:1342 [inline]
 __se_sys_openat fs/open.c:1337 [inline]
 __x64_sys_openat+0xef/0x110 fs/open.c:1337
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0xffff88823752d7e0 -> 0xffff88810ac47008

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 1826 Comm: syz-executor.3 Not tainted 6.1.0-rc4-syzkaller-00020-gf67dd6ce0723-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
==================================================================
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
device bridge_slave_0 entered promiscuous mode
bridge0: port 2(bridge_slave_1) entered blocking state
bridge0: port 2(bridge_slave_1) entered disabled state
device 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
device hsr_slave_0 entered promiscuous mode
device hsr_slave_1 entered promiscuous mode
debugfs: Directory 'hsr0' with parent 'hsr' already present!
Cannot create hsr debugfs directory
netdevsim netdevsim3 netdevsim0: renamed from eth0
netdevsim netdevsim3 netdevsim1: renamed from eth1
netdevsim netdevsim3 netdevsim2: renamed from eth2
netdevsim netdevsim3 netdevsim3: renamed from eth3
8021q: adding VLAN 0 to HW filter on device bond0
8021q: adding VLAN 0 to HW filter on device team0
hsr0: Slave A (hsr_slave_0) is not up; please bring it up to get a fully working HSR network
hsr0: Slave B (hsr_slave_1) is not up; please bring it up to get a fully working HSR network
8021q: adding VLAN 0 to HW filter on device batadv0
device veth0_vlan entered promiscuous mode
device veth1_vlan entered promiscuous mode
device veth0_macvtap entered promiscuous mode
device 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 netdevsim3 netdevsim0: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim3 netdevsim1: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim3 netdevsim2: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim3 netdevsim3: set [1, 0] type 2 family 0 port 6081 - 0

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/11/09 23:46 upstream f67dd6ce0723 bebca8b7 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in __d_lookup / __d_rehash
* Struck through repros no longer work on HEAD.