Extracting prog: 2m46.535639235s
Minimizing prog: 1h34m31.628606938s
Simplifying prog options: 13m50.369105324s
Extracting C: 5m20.319906888s
Simplifying C: 0s


extracting reproducer from 68 programs
testing a last program of every proc
single: executing 18 programs separately with timeout 6m0s
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-openat$kvm-ioctl$KVM_CREATE_VM-ioctl$KVM_CREATE_VCPU-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-socket$kcm-getpid-connect$unix-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
r1 = openat$kvm(0xffffffffffffff9c, &(0x7f0000000000), 0x40, 0x0)
r2 = ioctl$KVM_CREATE_VM(r1, 0xae01, 0x0)
ioctl$KVM_CREATE_VCPU(r2, 0xae41, 0x2)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
r3 = openat$tun(0xffffffffffffff9c, &(0x7f0000000000), 0x40a01, 0x0)
ioctl$TUNSETIFF(r3, 0x400454ca, &(0x7f0000000200)={'syzkaller1\x00', 0xc201})
socket$kcm(0x2, 0xa, 0x2)
getpid()
connect$unix(0xffffffffffffffff, &(0x7f000057eff8)=@abs, 0x6e)
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(&(0x7f0000000040)=ANY=[@ANYBLOB="040ed5000410"], 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program crashed: WARNING: suspicious RCU usage in proc_sys_compare
single: successfully extracted reproducer
found reproducer with 14 syscalls
minimizing guilty program
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-openat$kvm-ioctl$KVM_CREATE_VM-ioctl$KVM_CREATE_VCPU-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-socket$kcm-getpid-connect$unix-socket$nl_netfilter-preadv-syz_emit_vhci
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
r1 = openat$kvm(0xffffffffffffff9c, &(0x7f0000000000), 0x40, 0x0)
r2 = ioctl$KVM_CREATE_VM(r1, 0xae01, 0x0)
ioctl$KVM_CREATE_VCPU(r2, 0xae41, 0x2)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
r3 = openat$tun(0xffffffffffffff9c, &(0x7f0000000000), 0x40a01, 0x0)
ioctl$TUNSETIFF(r3, 0x400454ca, &(0x7f0000000200)={'syzkaller1\x00', 0xc201})
socket$kcm(0x2, 0xa, 0x2)
getpid()
connect$unix(0xffffffffffffffff, &(0x7f000057eff8)=@abs, 0x6e)
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(&(0x7f0000000040)=ANY=[@ANYBLOB="040ed5000410"], 0x11)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-openat$kvm-ioctl$KVM_CREATE_VM-ioctl$KVM_CREATE_VCPU-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-socket$kcm-getpid-connect$unix-socket$nl_netfilter-preadv-sendmsg$nl_generic
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
r1 = openat$kvm(0xffffffffffffff9c, &(0x7f0000000000), 0x40, 0x0)
r2 = ioctl$KVM_CREATE_VM(r1, 0xae01, 0x0)
ioctl$KVM_CREATE_VCPU(r2, 0xae41, 0x2)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
r3 = openat$tun(0xffffffffffffff9c, &(0x7f0000000000), 0x40a01, 0x0)
ioctl$TUNSETIFF(r3, 0x400454ca, &(0x7f0000000200)={'syzkaller1\x00', 0xc201})
socket$kcm(0x2, 0xa, 0x2)
getpid()
connect$unix(0xffffffffffffffff, &(0x7f000057eff8)=@abs, 0x6e)
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-openat$kvm-ioctl$KVM_CREATE_VM-ioctl$KVM_CREATE_VCPU-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-socket$kcm-getpid-connect$unix-socket$nl_netfilter-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
r1 = openat$kvm(0xffffffffffffff9c, &(0x7f0000000000), 0x40, 0x0)
r2 = ioctl$KVM_CREATE_VM(r1, 0xae01, 0x0)
ioctl$KVM_CREATE_VCPU(r2, 0xae41, 0x2)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
r3 = openat$tun(0xffffffffffffff9c, &(0x7f0000000000), 0x40a01, 0x0)
ioctl$TUNSETIFF(r3, 0x400454ca, &(0x7f0000000200)={'syzkaller1\x00', 0xc201})
socket$kcm(0x2, 0xa, 0x2)
getpid()
connect$unix(0xffffffffffffffff, &(0x7f000057eff8)=@abs, 0x6e)
socket$nl_netfilter(0x10, 0x3, 0xc)
syz_emit_vhci(&(0x7f0000000040)=ANY=[@ANYBLOB="040ed5000410"], 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-openat$kvm-ioctl$KVM_CREATE_VM-ioctl$KVM_CREATE_VCPU-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-socket$kcm-getpid-connect$unix-preadv-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
r1 = openat$kvm(0xffffffffffffff9c, &(0x7f0000000000), 0x40, 0x0)
r2 = ioctl$KVM_CREATE_VM(r1, 0xae01, 0x0)
ioctl$KVM_CREATE_VCPU(r2, 0xae41, 0x2)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
r3 = openat$tun(0xffffffffffffff9c, &(0x7f0000000000), 0x40a01, 0x0)
ioctl$TUNSETIFF(r3, 0x400454ca, &(0x7f0000000200)={'syzkaller1\x00', 0xc201})
socket$kcm(0x2, 0xa, 0x2)
getpid()
connect$unix(0xffffffffffffffff, &(0x7f000057eff8)=@abs, 0x6e)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(&(0x7f0000000040)=ANY=[@ANYBLOB="040ed5000410"], 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-openat$kvm-ioctl$KVM_CREATE_VM-ioctl$KVM_CREATE_VCPU-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-socket$kcm-getpid-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
r1 = openat$kvm(0xffffffffffffff9c, &(0x7f0000000000), 0x40, 0x0)
r2 = ioctl$KVM_CREATE_VM(r1, 0xae01, 0x0)
ioctl$KVM_CREATE_VCPU(r2, 0xae41, 0x2)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
r3 = openat$tun(0xffffffffffffff9c, &(0x7f0000000000), 0x40a01, 0x0)
ioctl$TUNSETIFF(r3, 0x400454ca, &(0x7f0000000200)={'syzkaller1\x00', 0xc201})
socket$kcm(0x2, 0xa, 0x2)
getpid()
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(&(0x7f0000000040)=ANY=[@ANYBLOB="040ed5000410"], 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program crashed: KASAN: slab-use-after-free Write in flush_tlb_func
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-openat$kvm-ioctl$KVM_CREATE_VM-ioctl$KVM_CREATE_VCPU-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-socket$kcm-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
r1 = openat$kvm(0xffffffffffffff9c, &(0x7f0000000000), 0x40, 0x0)
r2 = ioctl$KVM_CREATE_VM(r1, 0xae01, 0x0)
ioctl$KVM_CREATE_VCPU(r2, 0xae41, 0x2)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
r3 = openat$tun(0xffffffffffffff9c, &(0x7f0000000000), 0x40a01, 0x0)
ioctl$TUNSETIFF(r3, 0x400454ca, &(0x7f0000000200)={'syzkaller1\x00', 0xc201})
socket$kcm(0x2, 0xa, 0x2)
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(&(0x7f0000000040)=ANY=[@ANYBLOB="040ed5000410"], 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-openat$kvm-ioctl$KVM_CREATE_VM-ioctl$KVM_CREATE_VCPU-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-getpid-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
r1 = openat$kvm(0xffffffffffffff9c, &(0x7f0000000000), 0x40, 0x0)
r2 = ioctl$KVM_CREATE_VM(r1, 0xae01, 0x0)
ioctl$KVM_CREATE_VCPU(r2, 0xae41, 0x2)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
r3 = openat$tun(0xffffffffffffff9c, &(0x7f0000000000), 0x40a01, 0x0)
ioctl$TUNSETIFF(r3, 0x400454ca, &(0x7f0000000200)={'syzkaller1\x00', 0xc201})
getpid()
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(&(0x7f0000000040)=ANY=[@ANYBLOB="040ed5000410"], 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program crashed: WARNING: suspicious RCU usage in proc_sys_compare
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-openat$kvm-ioctl$KVM_CREATE_VM-ioctl$KVM_CREATE_VCPU-setsockopt$packet_int-openat$tun-getpid-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
r1 = openat$kvm(0xffffffffffffff9c, &(0x7f0000000000), 0x40, 0x0)
r2 = ioctl$KVM_CREATE_VM(r1, 0xae01, 0x0)
ioctl$KVM_CREATE_VCPU(r2, 0xae41, 0x2)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
openat$tun(0xffffffffffffff9c, &(0x7f0000000000), 0x40a01, 0x0)
getpid()
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(&(0x7f0000000040)=ANY=[@ANYBLOB="040ed5000410"], 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-openat$kvm-ioctl$KVM_CREATE_VM-ioctl$KVM_CREATE_VCPU-setsockopt$packet_int-ioctl$TUNSETIFF-getpid-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
r1 = openat$kvm(0xffffffffffffff9c, &(0x7f0000000000), 0x40, 0x0)
r2 = ioctl$KVM_CREATE_VM(r1, 0xae01, 0x0)
ioctl$KVM_CREATE_VCPU(r2, 0xae41, 0x2)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
ioctl$TUNSETIFF(0xffffffffffffffff, 0x400454ca, &(0x7f0000000200)={'syzkaller1\x00', 0xc201})
getpid()
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(&(0x7f0000000040)=ANY=[@ANYBLOB="040ed5000410"], 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program crashed: lost connection to test machine
suppressed program crash: lost connection to test machine
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-openat$kvm-ioctl$KVM_CREATE_VM-ioctl$KVM_CREATE_VCPU-openat$tun-ioctl$TUNSETIFF-getpid-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
socket(0x11, 0x3, 0x0)
r0 = openat$kvm(0xffffffffffffff9c, &(0x7f0000000000), 0x40, 0x0)
r1 = ioctl$KVM_CREATE_VM(r0, 0xae01, 0x0)
ioctl$KVM_CREATE_VCPU(r1, 0xae41, 0x2)
r2 = openat$tun(0xffffffffffffff9c, &(0x7f0000000000), 0x40a01, 0x0)
ioctl$TUNSETIFF(r2, 0x400454ca, &(0x7f0000000200)={'syzkaller1\x00', 0xc201})
getpid()
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(&(0x7f0000000040)=ANY=[@ANYBLOB="040ed5000410"], 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-openat$kvm-ioctl$KVM_CREATE_VM-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-getpid-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
r1 = openat$kvm(0xffffffffffffff9c, &(0x7f0000000000), 0x40, 0x0)
ioctl$KVM_CREATE_VM(r1, 0xae01, 0x0)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
r2 = openat$tun(0xffffffffffffff9c, &(0x7f0000000000), 0x40a01, 0x0)
ioctl$TUNSETIFF(r2, 0x400454ca, &(0x7f0000000200)={'syzkaller1\x00', 0xc201})
getpid()
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(&(0x7f0000000040)=ANY=[@ANYBLOB="040ed5000410"], 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program crashed: WARNING: suspicious RCU usage in proc_sys_compare
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-openat$kvm-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-getpid-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
openat$kvm(0xffffffffffffff9c, &(0x7f0000000000), 0x40, 0x0)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
r1 = openat$tun(0xffffffffffffff9c, &(0x7f0000000000), 0x40a01, 0x0)
ioctl$TUNSETIFF(r1, 0x400454ca, &(0x7f0000000200)={'syzkaller1\x00', 0xc201})
getpid()
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(&(0x7f0000000040)=ANY=[@ANYBLOB="040ed5000410"], 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-ioctl$KVM_CREATE_VM-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-getpid-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
ioctl$KVM_CREATE_VM(0xffffffffffffffff, 0xae01, 0x0)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
r1 = openat$tun(0xffffffffffffff9c, &(0x7f0000000000), 0x40a01, 0x0)
ioctl$TUNSETIFF(r1, 0x400454ca, &(0x7f0000000200)={'syzkaller1\x00', 0xc201})
getpid()
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(&(0x7f0000000040)=ANY=[@ANYBLOB="040ed5000410"], 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program crashed: KASAN: slab-use-after-free Write in flush_tlb_func
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): ioctl$KVM_CREATE_VM-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-getpid-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
ioctl$KVM_CREATE_VM(0xffffffffffffffff, 0xae01, 0x0)
setsockopt$packet_int(0xffffffffffffffff, 0x107, 0x7, 0x0, 0x0)
r0 = openat$tun(0xffffffffffffff9c, &(0x7f0000000000), 0x40a01, 0x0)
ioctl$TUNSETIFF(r0, 0x400454ca, &(0x7f0000000200)={'syzkaller1\x00', 0xc201})
getpid()
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(&(0x7f0000000040)=ANY=[@ANYBLOB="040ed5000410"], 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-ioctl$KVM_CREATE_VM-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-getpid-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
ioctl$KVM_CREATE_VM(0xffffffffffffffff, 0xae01, 0x0)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
r1 = openat$tun(0xffffffffffffff9c, 0x0, 0x40a01, 0x0)
ioctl$TUNSETIFF(r1, 0x400454ca, &(0x7f0000000200)={'syzkaller1\x00', 0xc201})
getpid()
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(&(0x7f0000000040)=ANY=[@ANYBLOB="040ed5000410"], 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program crashed: WARNING: suspicious RCU usage in proc_sys_compare
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-ioctl$KVM_CREATE_VM-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-getpid-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
ioctl$KVM_CREATE_VM(0xffffffffffffffff, 0xae01, 0x0)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
r1 = openat$tun(0xffffffffffffff9c, 0x0, 0x40a01, 0x0)
ioctl$TUNSETIFF(r1, 0x400454ca, 0x0)
getpid()
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(&(0x7f0000000040)=ANY=[@ANYBLOB="040ed5000410"], 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program crashed: KASAN: slab-use-after-free Write in flush_tlb_func
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-ioctl$KVM_CREATE_VM-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-getpid-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
ioctl$KVM_CREATE_VM(0xffffffffffffffff, 0xae01, 0x0)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
r1 = openat$tun(0xffffffffffffff9c, 0x0, 0x40a01, 0x0)
ioctl$TUNSETIFF(r1, 0x400454ca, 0x0)
getpid()
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(0x0, 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program crashed: KASAN: slab-use-after-free Write in flush_tlb_func
extracting C reproducer
testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-ioctl$KVM_CREATE_VM-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-getpid-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
program crashed: no output from test machine
a never seen crash title: no output from test machine, ignore
simplifying guilty program options
testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-ioctl$KVM_CREATE_VM-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-getpid-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
ioctl$KVM_CREATE_VM(0xffffffffffffffff, 0xae01, 0x0)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
r1 = openat$tun(0xffffffffffffff9c, 0x0, 0x40a01, 0x0)
ioctl$TUNSETIFF(r1, 0x400454ca, 0x0)
getpid()
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(0x0, 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program crashed: WARNING: suspicious RCU usage in proc_sys_compare
extracting C reproducer
testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-ioctl$KVM_CREATE_VM-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-getpid-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
program crashed: no output from test machine
a never seen crash title: no output from test machine, ignore
testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-ioctl$KVM_CREATE_VM-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-getpid-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
ioctl$KVM_CREATE_VM(0xffffffffffffffff, 0xae01, 0x0)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
r1 = openat$tun(0xffffffffffffff9c, 0x0, 0x40a01, 0x0)
ioctl$TUNSETIFF(r1, 0x400454ca, 0x0)
getpid()
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(0x0, 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program did not crash
testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-ioctl$KVM_CREATE_VM-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-getpid-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
ioctl$KVM_CREATE_VM(0xffffffffffffffff, 0xae01, 0x0)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
r1 = openat$tun(0xffffffffffffff9c, 0x0, 0x40a01, 0x0)
ioctl$TUNSETIFF(r1, 0x400454ca, 0x0)
getpid()
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(0x0, 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program crashed: KASAN: slab-use-after-free Write in flush_tlb_func
validation run: crashed=true
testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-ioctl$KVM_CREATE_VM-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-getpid-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
ioctl$KVM_CREATE_VM(0xffffffffffffffff, 0xae01, 0x0)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
r1 = openat$tun(0xffffffffffffff9c, 0x0, 0x40a01, 0x0)
ioctl$TUNSETIFF(r1, 0x400454ca, 0x0)
getpid()
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(0x0, 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program crashed: KASAN: slab-use-after-free Write in flush_tlb_func
validation run: crashed=true
testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-ioctl$KVM_CREATE_VM-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-getpid-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
ioctl$KVM_CREATE_VM(0xffffffffffffffff, 0xae01, 0x0)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
r1 = openat$tun(0xffffffffffffff9c, 0x0, 0x40a01, 0x0)
ioctl$TUNSETIFF(r1, 0x400454ca, 0x0)
getpid()
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(0x0, 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program did not crash
validation run: crashed=false
testing program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket-ioctl$KVM_CREATE_VM-setsockopt$packet_int-openat$tun-ioctl$TUNSETIFF-getpid-socket$nl_netfilter-preadv-syz_emit_vhci-sendmsg$nl_generic
detailed listing:
executing program 0:
r0 = socket(0x11, 0x3, 0x0)
ioctl$KVM_CREATE_VM(0xffffffffffffffff, 0xae01, 0x0)
setsockopt$packet_int(r0, 0x107, 0x7, 0x0, 0x0)
r1 = openat$tun(0xffffffffffffff9c, 0x0, 0x40a01, 0x0)
ioctl$TUNSETIFF(r1, 0x400454ca, 0x0)
getpid()
socket$nl_netfilter(0x10, 0x3, 0xc)
preadv(0xffffffffffffffff, 0x0, 0x0, 0x0, 0x0)
syz_emit_vhci(0x0, 0x11)
sendmsg$nl_generic(0xffffffffffffffff, 0x0, 0x20000000)

program crashed: WARNING: suspicious RCU usage in proc_sys_compare
validation run: crashed=true
reproducing took 2h14m5.801870176s
repro crashed as (corrupted=false):
=============================
WARNING: suspicious RCU usage
6.16.0-rc4-next-20250702-syzkaller #0 Not tainted
-----------------------------
fs/proc/proc_sysctl.c:934 suspicious rcu_dereference_check() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
3 locks held by syz-executor/5886:
 #0: ffff888034b02428 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
 #1: ffff8880330ef160 (&sb->s_type->i_mutex_key#10){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:884 [inline]
 #1: ffff8880330ef160 (&sb->s_type->i_mutex_key#10){++++}-{4:4}, at: open_last_lookups fs/namei.c:3806 [inline]
 #1: ffff8880330ef160 (&sb->s_type->i_mutex_key#10){++++}-{4:4}, at: path_openat+0x8cb/0x3830 fs/namei.c:4043
 #2: ffff888061050b18 (&lockref->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline]
 #2: ffff888061050b18 (&lockref->lock){+.+.}-{3:3}, at: d_wait_lookup fs/dcache.c:2537 [inline]
 #2: ffff888061050b18 (&lockref->lock){+.+.}-{3:3}, at: d_alloc_parallel+0xbe4/0x15e0 fs/dcache.c:2624

stack backtrace:
CPU: 0 UID: 0 PID: 5886 Comm: syz-executor Not tainted 6.16.0-rc4-next-20250702-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 lockdep_rcu_suspicious+0x140/0x1d0 kernel/locking/lockdep.c:6871
 proc_sys_compare+0x27d/0x2c0 fs/proc/proc_sysctl.c:934
 d_same_name fs/dcache.c:2179 [inline]
 d_alloc_parallel+0x1060/0x15e0 fs/dcache.c:2637
 lookup_open fs/namei.c:3630 [inline]
 open_last_lookups fs/namei.c:3807 [inline]
 path_openat+0xa3b/0x3830 fs/namei.c:4043
 do_filp_open+0x1fa/0x410 fs/namei.c:4073
 do_sys_openat2+0x121/0x1c0 fs/open.c:1434
 do_sys_open fs/open.c:1449 [inline]
 __do_sys_openat fs/open.c:1465 [inline]
 __se_sys_openat fs/open.c:1460 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1460
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f98b918d211
Code: 75 57 89 f0 25 00 00 41 00 3d 00 00 41 00 74 49 80 3d 3a 83 1f 00 00 74 6d 89 da 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 93 00 00 00 48 8b 54 24 28 64 48 2b 14 25
RSP: 002b:00007ffd6d228b00 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000080001 RCX: 00007f98b918d211
RDX: 0000000000080001 RSI: 00007f98b922aeb2 RDI: 00000000ffffff9c
RBP: 00007f98b922aeb2 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000015
R13: 00007ffd6d228ba0 R14: 0000000000000009 R15: 0000000000000000
 </TASK>

final repro crashed as (corrupted=false):
=============================
WARNING: suspicious RCU usage
6.16.0-rc4-next-20250702-syzkaller #0 Not tainted
-----------------------------
fs/proc/proc_sysctl.c:934 suspicious rcu_dereference_check() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
3 locks held by syz-executor/5886:
 #0: ffff888034b02428 (sb_writers#3){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:557
 #1: ffff8880330ef160 (&sb->s_type->i_mutex_key#10){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:884 [inline]
 #1: ffff8880330ef160 (&sb->s_type->i_mutex_key#10){++++}-{4:4}, at: open_last_lookups fs/namei.c:3806 [inline]
 #1: ffff8880330ef160 (&sb->s_type->i_mutex_key#10){++++}-{4:4}, at: path_openat+0x8cb/0x3830 fs/namei.c:4043
 #2: ffff888061050b18 (&lockref->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline]
 #2: ffff888061050b18 (&lockref->lock){+.+.}-{3:3}, at: d_wait_lookup fs/dcache.c:2537 [inline]
 #2: ffff888061050b18 (&lockref->lock){+.+.}-{3:3}, at: d_alloc_parallel+0xbe4/0x15e0 fs/dcache.c:2624

stack backtrace:
CPU: 0 UID: 0 PID: 5886 Comm: syz-executor Not tainted 6.16.0-rc4-next-20250702-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 lockdep_rcu_suspicious+0x140/0x1d0 kernel/locking/lockdep.c:6871
 proc_sys_compare+0x27d/0x2c0 fs/proc/proc_sysctl.c:934
 d_same_name fs/dcache.c:2179 [inline]
 d_alloc_parallel+0x1060/0x15e0 fs/dcache.c:2637
 lookup_open fs/namei.c:3630 [inline]
 open_last_lookups fs/namei.c:3807 [inline]
 path_openat+0xa3b/0x3830 fs/namei.c:4043
 do_filp_open+0x1fa/0x410 fs/namei.c:4073
 do_sys_openat2+0x121/0x1c0 fs/open.c:1434
 do_sys_open fs/open.c:1449 [inline]
 __do_sys_openat fs/open.c:1465 [inline]
 __se_sys_openat fs/open.c:1460 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1460
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f98b918d211
Code: 75 57 89 f0 25 00 00 41 00 3d 00 00 41 00 74 49 80 3d 3a 83 1f 00 00 74 6d 89 da 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 93 00 00 00 48 8b 54 24 28 64 48 2b 14 25
RSP: 002b:00007ffd6d228b00 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000080001 RCX: 00007f98b918d211
RDX: 0000000000080001 RSI: 00007f98b922aeb2 RDI: 00000000ffffff9c
RBP: 00007f98b922aeb2 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000015
R13: 00007ffd6d228ba0 R14: 0000000000000009 R15: 0000000000000000
 </TASK>