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KCSAN: data-race in data_push_tail / ip4_addr_string

Status: auto-obsoleted due to no activity on 2025/02/03 14:58
Subsystems: lvs
[Documentation on labels]
First crash: 264d, last: 264d

Sample crash report:
netdevsim netdevsim3 netdevsim0: renamed from eth0
netdevsim netdevsim3 netdevsim1: renamed from eth1
==================================================================
BUG: KCSAN: data-race in data_push_tail / ip4_addr_string

write to 0xffffffff88bd2b50 of 1 bytes by task 10789 on cpu 1:
 string_nocheck lib/vsprintf.c:650 [inline]
 ip4_addr_string+0xb5/0x140 lib/vsprintf.c:1515
 ip_addr_string+0x1be/0x5d0 lib/vsprintf.c:1628
 pointer+0x647/0xd20 lib/vsprintf.c:2473
 vsnprintf+0x861/0xe30 lib/vsprintf.c:2852
 vscnprintf+0x42/0x90 lib/vsprintf.c:2954
 printk_sprint+0x30/0x2d0 kernel/printk/printk.c:2216
 vprintk_store+0x589/0x870 kernel/printk/printk.c:2336
 vprintk_emit+0x15e/0x680 kernel/printk/printk.c:2408
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2447
 vprintk+0x75/0x80 kernel/printk/printk_safe.c:86
 _printk+0x7a/0xa0 kernel/printk/printk.c:2457
 ip_vs_scheduler_err+0x186/0x190
 ip_vs_wlc_schedule+0xa0/0x1d0 net/netfilter/ipvs/ip_vs_wlc.c:58
 ip_vs_sched_persist net/netfilter/ipvs/ip_vs_core.c:353 [inline]
 ip_vs_schedule+0x931/0xeb0 net/netfilter/ipvs/ip_vs_core.c:508
 udp_conn_schedule+0x248/0x3b0 net/netfilter/ipvs/ip_vs_proto_udp.c:78
 ip_vs_try_to_schedule net/netfilter/ipvs/ip_vs_core.c:1482 [inline]
 ip_vs_in_hook+0x5d2/0x1210 net/netfilter/ipvs/ip_vs_core.c:2054
 nf_hook_entry_hookfn include/linux/netfilter.h:154 [inline]
 nf_hook_slow+0x86/0x1b0 net/netfilter/core.c:626
 nf_hook include/linux/netfilter.h:269 [inline]
 __ip_local_out+0x2d6/0x300 net/ipv4/ip_output.c:119
 ip_local_out net/ipv4/ip_output.c:128 [inline]
 ip_send_skb+0x30/0x140 net/ipv4/ip_output.c:1505
 udp_send_skb+0x6a6/0x9f0 net/ipv4/udp.c:1142
 udp_sendmsg+0x1257/0x12f0 net/ipv4/udp.c:1430
 inet_sendmsg+0xaf/0xd0 net/ipv4/af_inet.c:851
 sock_sendmsg_nosec net/socket.c:711 [inline]
 __sock_sendmsg+0x102/0x180 net/socket.c:726
 ____sys_sendmsg+0x312/0x410 net/socket.c:2583
 ___sys_sendmsg net/socket.c:2637 [inline]
 __sys_sendmmsg+0x227/0x4b0 net/socket.c:2726
 __do_sys_sendmmsg net/socket.c:2753 [inline]
 __se_sys_sendmmsg net/socket.c:2750 [inline]
 __x64_sys_sendmmsg+0x57/0x70 net/socket.c:2750
 x64_sys_call+0x29aa/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:308
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff88bd2b50 of 8 bytes by task 10740 on cpu 0:
 data_make_reusable kernel/printk/printk_ringbuffer.c:594 [inline]
 data_push_tail+0x102/0x430 kernel/printk/printk_ringbuffer.c:679
 data_alloc+0xbe/0x2c0 kernel/printk/printk_ringbuffer.c:1054
 prb_reserve+0x85e/0xb60 kernel/printk/printk_ringbuffer.c:1669
 vprintk_store+0x558/0x870 kernel/printk/printk.c:2326
 vprintk_emit+0x15e/0x680 kernel/printk/printk.c:2408
 dev_vprintk_emit+0x1df/0x210 drivers/base/core.c:4935
 dev_printk_emit+0x82/0xb0 drivers/base/core.c:4946
 __netdev_printk+0x352/0x3e0 net/core/dev.c:11938
 netdev_info+0x99/0xc0 net/core/dev.c:11993
 dev_change_name+0x5a5/0x610 net/core/dev.c:1243
 do_setlink+0x524/0x22c0 net/core/rtnetlink.c:3089
 rtnl_changelink net/core/rtnetlink.c:3723 [inline]
 __rtnl_newlink net/core/rtnetlink.c:3874 [inline]
 rtnl_newlink+0xdbe/0x1220 net/core/rtnetlink.c:4009
 rtnetlink_rcv_msg+0x651/0x710 net/core/rtnetlink.c:6919
 netlink_rcv_skb+0x12c/0x230 net/netlink/af_netlink.c:2542
 rtnetlink_rcv+0x1c/0x30 net/core/rtnetlink.c:6946
 netlink_unicast_kernel net/netlink/af_netlink.c:1321 [inline]
 netlink_unicast+0x599/0x670 net/netlink/af_netlink.c:1347
 netlink_sendmsg+0x5cc/0x6e0 net/netlink/af_netlink.c:1891
 sock_sendmsg_nosec net/socket.c:711 [inline]
 __sock_sendmsg+0x140/0x180 net/socket.c:726
 __sys_sendto+0x1a8/0x230 net/socket.c:2197
 __do_sys_sendto net/socket.c:2204 [inline]
 __se_sys_sendto net/socket.c:2200 [inline]
 __x64_sys_sendto+0x78/0x90 net/socket.c:2200
 x64_sys_call+0x29fa/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00000000ffffed26 -> 0x206f6e202d20303a

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 10740 Comm: syz-executor Not tainted 6.13.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
==================================================================
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
veth0_vlan: entered promiscuous mode
veth1_vlan: entered promiscuous mode
veth0_macvtap: entered promiscuous mode
veth1_macvtap: entered promiscuous mode
batman_adv: batadv0: Interface activated: batadv_slave_0
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
2024/12/09 14:56 upstream fac04efc5c79 9ac0fdc6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in data_push_tail / ip4_addr_string
* Struck through repros no longer work on HEAD.