Extracting prog: 1m56.781804818s
Minimizing prog: 27m32.749092313s
Simplifying prog options: 0s
Extracting C: 46.994441741s
Simplifying C: 25m10.789651913s


extracting reproducer from 15 programs
first checking the prog from the crash report
single: executing 1 programs separately with timeout 30s
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet-bind$inet-listen-dup2-mkdirat-mount-openat-write-openat-write
detailed listing:
executing program 0:
r0 = socket$inet(0x2, 0x1, 0x0)
bind$inet(r0, &(0x7f0000000400)={0x2, 0x801, @empty}, 0x10)
listen(r0, 0x5)
dup2(r0, 0xa)
mkdirat(0xffffffffffffff9c, &(0x7f0000000000)='./nfsd\x00', 0x1ff)
mount(0x0, &(0x7f0000000000)='./nfsd\x00', &(0x7f0000000040)='nfsd\x00', 0x0, 0x0)
r1 = openat(0xffffffffffffff9c, &(0x7f0000000080)='./nfsd/portlist\x00', 0x2, 0x0)
write(r1, &(0x7f00000000c0)='10\n', 0x3)
r2 = openat(0xffffffffffffff9c, &(0x7f0000000100)='./nfsd/threads\x00', 0x2, 0x0)
write(r2, &(0x7f0000000140)='1\n', 0x2)

program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
single: successfully extracted reproducer
found reproducer with 10 syscalls
minimizing guilty program
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet-bind$inet-listen-dup2-mkdirat-mount-openat-write-openat
detailed listing:
executing program 0:
r0 = socket$inet(0x2, 0x1, 0x0)
bind$inet(r0, &(0x7f0000000400)={0x2, 0x801, @empty}, 0x10)
listen(r0, 0x5)
dup2(r0, 0xa)
mkdirat(0xffffffffffffff9c, &(0x7f0000000000)='./nfsd\x00', 0x1ff)
mount(0x0, &(0x7f0000000000)='./nfsd\x00', &(0x7f0000000040)='nfsd\x00', 0x0, 0x0)
r1 = openat(0xffffffffffffff9c, &(0x7f0000000080)='./nfsd/portlist\x00', 0x2, 0x0)
write(r1, &(0x7f00000000c0)='10\n', 0x3)
openat(0xffffffffffffff9c, &(0x7f0000000100)='./nfsd/threads\x00', 0x2, 0x0)

program did not crash
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet-bind$inet-listen-dup2-mkdirat-mount-openat-write-write
detailed listing:
executing program 0:
r0 = socket$inet(0x2, 0x1, 0x0)
bind$inet(r0, &(0x7f0000000400)={0x2, 0x801, @empty}, 0x10)
listen(r0, 0x5)
dup2(r0, 0xa)
mkdirat(0xffffffffffffff9c, &(0x7f0000000000)='./nfsd\x00', 0x1ff)
mount(0x0, &(0x7f0000000000)='./nfsd\x00', &(0x7f0000000040)='nfsd\x00', 0x0, 0x0)
r1 = openat(0xffffffffffffff9c, &(0x7f0000000080)='./nfsd/portlist\x00', 0x2, 0x0)
write(r1, &(0x7f00000000c0)='10\n', 0x3)
write(0xffffffffffffffff, &(0x7f0000000140)='1\n', 0x2)

program did not crash
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet-bind$inet-listen-dup2-mkdirat-mount-openat-openat-write
detailed listing:
executing program 0:
r0 = socket$inet(0x2, 0x1, 0x0)
bind$inet(r0, &(0x7f0000000400)={0x2, 0x801, @empty}, 0x10)
listen(r0, 0x5)
dup2(r0, 0xa)
mkdirat(0xffffffffffffff9c, &(0x7f0000000000)='./nfsd\x00', 0x1ff)
mount(0x0, &(0x7f0000000000)='./nfsd\x00', &(0x7f0000000040)='nfsd\x00', 0x0, 0x0)
openat(0xffffffffffffff9c, &(0x7f0000000080)='./nfsd/portlist\x00', 0x2, 0x0)
r1 = openat(0xffffffffffffff9c, &(0x7f0000000100)='./nfsd/threads\x00', 0x2, 0x0)
write(r1, &(0x7f0000000140)='1\n', 0x2)

program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet-bind$inet-listen-dup2-mkdirat-mount-openat-write
detailed listing:
executing program 0:
r0 = socket$inet(0x2, 0x1, 0x0)
bind$inet(r0, &(0x7f0000000400)={0x2, 0x801, @empty}, 0x10)
listen(r0, 0x5)
dup2(r0, 0xa)
mkdirat(0xffffffffffffff9c, &(0x7f0000000000)='./nfsd\x00', 0x1ff)
mount(0x0, &(0x7f0000000000)='./nfsd\x00', &(0x7f0000000040)='nfsd\x00', 0x0, 0x0)
r1 = openat(0xffffffffffffff9c, &(0x7f0000000100)='./nfsd/threads\x00', 0x2, 0x0)
write(r1, &(0x7f0000000140)='1\n', 0x2)

program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet-bind$inet-listen-dup2-mkdirat-openat-write
detailed listing:
executing program 0:
r0 = socket$inet(0x2, 0x1, 0x0)
bind$inet(r0, &(0x7f0000000400)={0x2, 0x801, @empty}, 0x10)
listen(r0, 0x5)
dup2(r0, 0xa)
mkdirat(0xffffffffffffff9c, &(0x7f0000000000)='./nfsd\x00', 0x1ff)
r1 = openat(0xffffffffffffff9c, &(0x7f0000000100)='./nfsd/threads\x00', 0x2, 0x0)
write(r1, &(0x7f0000000140)='1\n', 0x2)

program did not crash
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet-bind$inet-listen-dup2-mount-openat-write
detailed listing:
executing program 0:
r0 = socket$inet(0x2, 0x1, 0x0)
bind$inet(r0, &(0x7f0000000400)={0x2, 0x801, @empty}, 0x10)
listen(r0, 0x5)
dup2(r0, 0xa)
mount(0x0, &(0x7f0000000000)='./nfsd\x00', &(0x7f0000000040)='nfsd\x00', 0x0, 0x0)
r1 = openat(0xffffffffffffff9c, &(0x7f0000000100)='./nfsd/threads\x00', 0x2, 0x0)
write(r1, &(0x7f0000000140)='1\n', 0x2)

program did not crash
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet-bind$inet-listen-mkdirat-mount-openat-write
detailed listing:
executing program 0:
r0 = socket$inet(0x2, 0x1, 0x0)
bind$inet(r0, &(0x7f0000000400)={0x2, 0x801, @empty}, 0x10)
listen(r0, 0x5)
mkdirat(0xffffffffffffff9c, &(0x7f0000000000)='./nfsd\x00', 0x1ff)
mount(0x0, &(0x7f0000000000)='./nfsd\x00', &(0x7f0000000040)='nfsd\x00', 0x0, 0x0)
r1 = openat(0xffffffffffffff9c, &(0x7f0000000100)='./nfsd/threads\x00', 0x2, 0x0)
write(r1, &(0x7f0000000140)='1\n', 0x2)

program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet-bind$inet-mkdirat-mount-openat-write
detailed listing:
executing program 0:
r0 = socket$inet(0x2, 0x1, 0x0)
bind$inet(r0, &(0x7f0000000400)={0x2, 0x801, @empty}, 0x10)
mkdirat(0xffffffffffffff9c, &(0x7f0000000000)='./nfsd\x00', 0x1ff)
mount(0x0, &(0x7f0000000000)='./nfsd\x00', &(0x7f0000000040)='nfsd\x00', 0x0, 0x0)
r1 = openat(0xffffffffffffff9c, &(0x7f0000000100)='./nfsd/threads\x00', 0x2, 0x0)
write(r1, &(0x7f0000000140)='1\n', 0x2)

program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet-mkdirat-mount-openat-write
detailed listing:
executing program 0:
socket$inet(0x2, 0x1, 0x0)
mkdirat(0xffffffffffffff9c, &(0x7f0000000000)='./nfsd\x00', 0x1ff)
mount(0x0, &(0x7f0000000000)='./nfsd\x00', &(0x7f0000000040)='nfsd\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f0000000100)='./nfsd/threads\x00', 0x2, 0x0)
write(r0, &(0x7f0000000140)='1\n', 0x2)

program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000000)='./nfsd\x00', 0x1ff)
mount(0x0, &(0x7f0000000000)='./nfsd\x00', &(0x7f0000000040)='nfsd\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f0000000100)='./nfsd/threads\x00', 0x2, 0x0)
write(r0, &(0x7f0000000140)='1\n', 0x2)

program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, 0x0, 0x1ff)
mount(0x0, &(0x7f0000000000)='./nfsd\x00', &(0x7f0000000040)='nfsd\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f0000000100)='./nfsd/threads\x00', 0x2, 0x0)
write(r0, &(0x7f0000000140)='1\n', 0x2)

program did not crash
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000000)='./nfsd\x00', 0x1ff)
mount(0x0, 0x0, &(0x7f0000000040)='nfsd\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f0000000100)='./nfsd/threads\x00', 0x2, 0x0)
write(r0, &(0x7f0000000140)='1\n', 0x2)

program did not crash
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000000)='./nfsd\x00', 0x1ff)
mount(0x0, &(0x7f0000000000)='./nfsd\x00', 0x0, 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f0000000100)='./nfsd/threads\x00', 0x2, 0x0)
write(r0, &(0x7f0000000140)='1\n', 0x2)

program did not crash
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000000)='./nfsd\x00', 0x1ff)
mount(0x0, &(0x7f0000000000)='./nfsd\x00', &(0x7f0000000040)='nfsd\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, 0x0, 0x2, 0x0)
write(r0, &(0x7f0000000140)='1\n', 0x2)

program did not crash
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000000)='./nfsd\x00', 0x1ff)
mount(0x0, &(0x7f0000000000)='./nfsd\x00', &(0x7f0000000040)='nfsd\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f0000000100)='./nfsd/threads\x00', 0x2, 0x0)
write(r0, 0x0, 0x0)

program did not crash
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000000)='./nfsd\x00', 0x1ff)
mount(0x0, &(0x7f0000000000)='./nfsd\x00', &(0x7f0000000040)='nfsd\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f0000000100)='./nfsd/threads\x00', 0x2, 0x0)
write(r0, &(0x7f0000000140), 0x0)

program did not crash
extracting C reproducer
testing compiled C program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
simplifying C reproducer
testing compiled C program (duration=30s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
testing compiled C program (duration=30s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:false Cgroups:false 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
testing compiled C program (duration=30s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:true Sysctl:true Swap:false UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
program did not crash
testing compiled C program (duration=30s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:false Cgroups:false 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
testing compiled C program (duration=30s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
testing compiled C program (duration=30s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false 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 CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
testing compiled C program (duration=30s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
testing compiled C program (duration=30s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
testing compiled C program (duration=30s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
testing compiled C program (duration=30s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
testing compiled C program (duration=30s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
testing compiled C program (duration=30s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:false HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
testing compiled C program (duration=30s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
testing compiled C program (duration=30s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:true UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
testing compiled C program (duration=30s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
testing program (duration=30s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000000)='./nfsd\x00', 0x1ff)
mount(0x0, &(0x7f0000000000)='./nfsd\x00', &(0x7f0000000040)='nfsd\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f0000000100)='./nfsd/threads\x00', 0x2, 0x0)
write(r0, &(0x7f0000000140)='1\n', 0x2)

program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
validation run: crashed=true
testing program (duration=30s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000000)='./nfsd\x00', 0x1ff)
mount(0x0, &(0x7f0000000000)='./nfsd\x00', &(0x7f0000000040)='nfsd\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f0000000100)='./nfsd/threads\x00', 0x2, 0x0)
write(r0, &(0x7f0000000140)='1\n', 0x2)

program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
validation run: crashed=true
testing program (duration=30s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000000)='./nfsd\x00', 0x1ff)
mount(0x0, &(0x7f0000000000)='./nfsd\x00', &(0x7f0000000040)='nfsd\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f0000000100)='./nfsd/threads\x00', 0x2, 0x0)
write(r0, &(0x7f0000000140)='1\n', 0x2)

program crashed: KASAN: use-after-free Write in nfsd_shutdown_threads
validation run: crashed=true
reproducing took 1h0m33.533262388s
repro crashed as (corrupted=false):
==================================================================
BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
BUG: KASAN: use-after-free in atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:111 [inline]
BUG: KASAN: use-after-free in __refcount_add include/linux/refcount.h:193 [inline]
BUG: KASAN: use-after-free in __refcount_inc include/linux/refcount.h:250 [inline]
BUG: KASAN: use-after-free in refcount_inc include/linux/refcount.h:267 [inline]
BUG: KASAN: use-after-free in kref_get include/linux/kref.h:45 [inline]
BUG: KASAN: use-after-free in svc_get include/linux/sunrpc/svc.h:108 [inline]
BUG: KASAN: use-after-free in nfsd_shutdown_threads+0x89/0x1a0 fs/nfsd/nfssvc.c:641
Write of size 4 at addr ffff88807a263450 by task syz-executor/4304

CPU: 0 PID: 4304 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 print_address_description+0x60/0x2d0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0xdf/0x130 mm/kasan/report.c:451
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x235/0x290 mm/kasan/generic.c:189
 instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
 atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:111 [inline]
 __refcount_add include/linux/refcount.h:193 [inline]
 __refcount_inc include/linux/refcount.h:250 [inline]
 refcount_inc include/linux/refcount.h:267 [inline]
 kref_get include/linux/kref.h:45 [inline]
 svc_get include/linux/sunrpc/svc.h:108 [inline]
 nfsd_shutdown_threads+0x89/0x1a0 fs/nfsd/nfssvc.c:641
 nfsd_umount+0x3e/0xc0 fs/nfsd/nfsctl.c:1411
 deactivate_locked_super+0x93/0xf0 fs/super.c:335
 cleanup_mnt+0x426/0x4d0 fs/namespace.c:1148
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:184
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:217
 __syscall_exit_to_user_mode_work kernel/entry/common.c:299 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:310
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f131eb46397
Code: a2 c7 05 5c 43 25 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffda5f7c718 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f131ebdb4bb RCX: 00007f131eb46397
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffda5f7c7d0
RBP: 00007ffda5f7c7d0 R08: 00007ffda5f7d7d0 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffda5f7d860
R13: 00007f131ebdb4bb R14: 0000000000013fc9 R15: 00007ffda5f7d8a0
 </TASK>

Allocated by task 4317:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 ____kasan_kmalloc mm/kasan/common.c:513 [inline]
 __kasan_kmalloc+0xaf/0xe0 mm/kasan/common.c:522
 kmalloc include/linux/slab.h:607 [inline]
 kzalloc include/linux/slab.h:738 [inline]
 __svc_create+0x60/0x9d0 net/sunrpc/svc.c:485
 svc_create_pooled+0x62f/0x810 net/sunrpc/svc.c:573
 nfsd_create_serv+0x2f9/0x700 fs/nfsd/nfssvc.c:668
 nfsd_svc+0x132/0x9e0 fs/nfsd/nfssvc.c:798
 write_threads+0x2ea/0x350 fs/nfsd/nfsctl.c:426
 nfsctl_transaction_write+0x105/0x150 fs/nfsd/nfsctl.c:114
 vfs_write+0x304/0xd70 fs/read_write.c:592
 ksys_write+0x153/0x260 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Freed by task 4317:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:46
 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1710 [inline]
 slab_free_freelist_hook+0xec/0x170 mm/slub.c:1736
 slab_free mm/slub.c:3504 [inline]
 kfree+0xef/0x2a0 mm/slub.c:4564
 kref_put include/linux/kref.h:65 [inline]
 svc_put include/linux/sunrpc/svc.h:123 [inline]
 nfsd_svc+0x7cf/0x9e0 fs/nfsd/nfssvc.c:821
 write_threads+0x2ea/0x350 fs/nfsd/nfsctl.c:426
 nfsctl_transaction_write+0x105/0x150 fs/nfsd/nfsctl.c:114
 vfs_write+0x304/0xd70 fs/read_write.c:592
 ksys_write+0x153/0x260 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

The buggy address belongs to the object at ffff88807a263400
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 80 bytes inside of
 512-byte region [ffff88807a263400, ffff88807a263600)
The buggy address belongs to the page:
page:ffffea0001e89800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7a260
head:ffffea0001e89800 order:2 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 0000000d00000001 ffff888016c41c80
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3557, ts 27733172051, free_ts 25026032964
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x24f6/0x2670 mm/page_alloc.c:4192
 __alloc_pages+0x1ee/0x480 mm/page_alloc.c:5501
 alloc_slab_page mm/slub.c:1780 [inline]
 allocate_slab mm/slub.c:1917 [inline]
 new_slab+0xc0/0x4b0 mm/slub.c:1980
 ___slab_alloc+0x807/0xdd0 mm/slub.c:3013
 __slab_alloc mm/slub.c:3100 [inline]
 slab_alloc_node mm/slub.c:3191 [inline]
 slab_alloc mm/slub.c:3233 [inline]
 kmem_cache_alloc_trace+0xf9/0x290 mm/slub.c:3250
 kmalloc include/linux/slab.h:607 [inline]
 kzalloc include/linux/slab.h:738 [inline]
 kernfs_fop_open+0x3c9/0xba0 fs/kernfs/file.c:628
 do_dentry_open+0x7f7/0xf90 fs/open.c:826
 do_open fs/namei.c:3659 [inline]
 path_openat+0x2718/0x2fb0 fs/namei.c:3793
 do_filp_open+0x1df/0x400 fs/namei.c:3820
 do_sys_openat2+0x14b/0x500 fs/open.c:1255
 do_sys_open fs/open.c:1271 [inline]
 __do_sys_openat fs/open.c:1287 [inline]
 __se_sys_openat fs/open.c:1282 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1282
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1340 [inline]
 free_pcp_prepare mm/page_alloc.c:1391 [inline]
 free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317
 free_unref_page+0x8f/0x2a0 mm/page_alloc.c:3396
 free_contig_range+0x96/0xf0 mm/page_alloc.c:9428
 destroy_args+0xef/0xa00 mm/debug_vm_pgtable.c:1018
 debug_vm_pgtable+0x321/0x380 mm/debug_vm_pgtable.c:1336
 do_one_initcall+0x272/0x730 init/main.c:1276
 do_initcall_level+0x13d/0x1f0 init/main.c:1349
 do_initcalls+0x4b/0x90 init/main.c:1365
 kernel_init_freeable+0x3d5/0x560 init/main.c:1589
 kernel_init+0x19/0x1b0 init/main.c:1480
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

Memory state around the buggy address:
 ffff88807a263300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807a263380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88807a263400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                 ^
 ffff88807a263480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807a263500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

final repro crashed as (corrupted=false):
==================================================================
BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
BUG: KASAN: use-after-free in atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:111 [inline]
BUG: KASAN: use-after-free in __refcount_add include/linux/refcount.h:193 [inline]
BUG: KASAN: use-after-free in __refcount_inc include/linux/refcount.h:250 [inline]
BUG: KASAN: use-after-free in refcount_inc include/linux/refcount.h:267 [inline]
BUG: KASAN: use-after-free in kref_get include/linux/kref.h:45 [inline]
BUG: KASAN: use-after-free in svc_get include/linux/sunrpc/svc.h:108 [inline]
BUG: KASAN: use-after-free in nfsd_shutdown_threads+0x89/0x1a0 fs/nfsd/nfssvc.c:641
Write of size 4 at addr ffff88807a263450 by task syz-executor/4304

CPU: 0 PID: 4304 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 print_address_description+0x60/0x2d0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0xdf/0x130 mm/kasan/report.c:451
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x235/0x290 mm/kasan/generic.c:189
 instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
 atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:111 [inline]
 __refcount_add include/linux/refcount.h:193 [inline]
 __refcount_inc include/linux/refcount.h:250 [inline]
 refcount_inc include/linux/refcount.h:267 [inline]
 kref_get include/linux/kref.h:45 [inline]
 svc_get include/linux/sunrpc/svc.h:108 [inline]
 nfsd_shutdown_threads+0x89/0x1a0 fs/nfsd/nfssvc.c:641
 nfsd_umount+0x3e/0xc0 fs/nfsd/nfsctl.c:1411
 deactivate_locked_super+0x93/0xf0 fs/super.c:335
 cleanup_mnt+0x426/0x4d0 fs/namespace.c:1148
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:184
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:217
 __syscall_exit_to_user_mode_work kernel/entry/common.c:299 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:310
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f131eb46397
Code: a2 c7 05 5c 43 25 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffda5f7c718 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f131ebdb4bb RCX: 00007f131eb46397
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffda5f7c7d0
RBP: 00007ffda5f7c7d0 R08: 00007ffda5f7d7d0 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffda5f7d860
R13: 00007f131ebdb4bb R14: 0000000000013fc9 R15: 00007ffda5f7d8a0
 </TASK>

Allocated by task 4317:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 ____kasan_kmalloc mm/kasan/common.c:513 [inline]
 __kasan_kmalloc+0xaf/0xe0 mm/kasan/common.c:522
 kmalloc include/linux/slab.h:607 [inline]
 kzalloc include/linux/slab.h:738 [inline]
 __svc_create+0x60/0x9d0 net/sunrpc/svc.c:485
 svc_create_pooled+0x62f/0x810 net/sunrpc/svc.c:573
 nfsd_create_serv+0x2f9/0x700 fs/nfsd/nfssvc.c:668
 nfsd_svc+0x132/0x9e0 fs/nfsd/nfssvc.c:798
 write_threads+0x2ea/0x350 fs/nfsd/nfsctl.c:426
 nfsctl_transaction_write+0x105/0x150 fs/nfsd/nfsctl.c:114
 vfs_write+0x304/0xd70 fs/read_write.c:592
 ksys_write+0x153/0x260 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Freed by task 4317:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:46
 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1710 [inline]
 slab_free_freelist_hook+0xec/0x170 mm/slub.c:1736
 slab_free mm/slub.c:3504 [inline]
 kfree+0xef/0x2a0 mm/slub.c:4564
 kref_put include/linux/kref.h:65 [inline]
 svc_put include/linux/sunrpc/svc.h:123 [inline]
 nfsd_svc+0x7cf/0x9e0 fs/nfsd/nfssvc.c:821
 write_threads+0x2ea/0x350 fs/nfsd/nfsctl.c:426
 nfsctl_transaction_write+0x105/0x150 fs/nfsd/nfsctl.c:114
 vfs_write+0x304/0xd70 fs/read_write.c:592
 ksys_write+0x153/0x260 fs/read_write.c:647
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

The buggy address belongs to the object at ffff88807a263400
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 80 bytes inside of
 512-byte region [ffff88807a263400, ffff88807a263600)
The buggy address belongs to the page:
page:ffffea0001e89800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7a260
head:ffffea0001e89800 order:2 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 0000000d00000001 ffff888016c41c80
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3557, ts 27733172051, free_ts 25026032964
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x24f6/0x2670 mm/page_alloc.c:4192
 __alloc_pages+0x1ee/0x480 mm/page_alloc.c:5501
 alloc_slab_page mm/slub.c:1780 [inline]
 allocate_slab mm/slub.c:1917 [inline]
 new_slab+0xc0/0x4b0 mm/slub.c:1980
 ___slab_alloc+0x807/0xdd0 mm/slub.c:3013
 __slab_alloc mm/slub.c:3100 [inline]
 slab_alloc_node mm/slub.c:3191 [inline]
 slab_alloc mm/slub.c:3233 [inline]
 kmem_cache_alloc_trace+0xf9/0x290 mm/slub.c:3250
 kmalloc include/linux/slab.h:607 [inline]
 kzalloc include/linux/slab.h:738 [inline]
 kernfs_fop_open+0x3c9/0xba0 fs/kernfs/file.c:628
 do_dentry_open+0x7f7/0xf90 fs/open.c:826
 do_open fs/namei.c:3659 [inline]
 path_openat+0x2718/0x2fb0 fs/namei.c:3793
 do_filp_open+0x1df/0x400 fs/namei.c:3820
 do_sys_openat2+0x14b/0x500 fs/open.c:1255
 do_sys_open fs/open.c:1271 [inline]
 __do_sys_openat fs/open.c:1287 [inline]
 __se_sys_openat fs/open.c:1282 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1282
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1340 [inline]
 free_pcp_prepare mm/page_alloc.c:1391 [inline]
 free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317
 free_unref_page+0x8f/0x2a0 mm/page_alloc.c:3396
 free_contig_range+0x96/0xf0 mm/page_alloc.c:9428
 destroy_args+0xef/0xa00 mm/debug_vm_pgtable.c:1018
 debug_vm_pgtable+0x321/0x380 mm/debug_vm_pgtable.c:1336
 do_one_initcall+0x272/0x730 init/main.c:1276
 do_initcall_level+0x13d/0x1f0 init/main.c:1349
 do_initcalls+0x4b/0x90 init/main.c:1365
 kernel_init_freeable+0x3d5/0x560 init/main.c:1589
 kernel_init+0x19/0x1b0 init/main.c:1480
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

Memory state around the buggy address:
 ffff88807a263300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807a263380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88807a263400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                 ^
 ffff88807a263480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807a263500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================