Extracting prog: 1m8.726941507s
Minimizing prog: 7m21.004287171s
Simplifying prog options: 1m46.666510419s
Extracting C: 35.178877575s
Simplifying C: 0s


extracting reproducer from 1 programs
testing a last program of every proc
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: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}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-sendfile-syz_clone3-ioctl$EXT4_IOC_GETFSUUID
detailed listing:
executing program 0:
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
r1 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, &(0x7f0000000240)=@pppol2tpin6={0x18, 0x1, {0x0, r1, 0x8, 0x0, 0x0, 0x0, {0xa, 0x0, 0x0, @rand_addr=' \x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02'}}}, 0x32)
sendfile(0xffffffffffffffff, 0xffffffffffffffff, &(0x7f0000000040)=0x3, 0xac5)
syz_clone3(&(0x7f0000000900)={0x23800000, &(0x7f0000000040)=<r2=>0xffffffffffffffff, 0x0, 0x0, {0x27}, 0x0, 0x0, 0x0, 0x0}, 0x58)
ioctl$EXT4_IOC_GETFSUUID(r2, 0x80047453, 0x0)

program crashed: KASAN: use-after-free Write in rcu_segcblist_enqueue
single: successfully extracted reproducer
found reproducer with 6 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: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}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-sendfile-syz_clone3
detailed listing:
executing program 0:
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
r1 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, &(0x7f0000000240)=@pppol2tpin6={0x18, 0x1, {0x0, r1, 0x8, 0x0, 0x0, 0x0, {0xa, 0x0, 0x0, @rand_addr=' \x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02'}}}, 0x32)
sendfile(0xffffffffffffffff, 0xffffffffffffffff, &(0x7f0000000040)=0x3, 0xac5)
syz_clone3(&(0x7f0000000900)={0x23800000, &(0x7f0000000040), 0x0, 0x0, {0x27}, 0x0, 0x0, 0x0, 0x0}, 0x58)

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: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}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-sendfile-ioctl$EXT4_IOC_GETFSUUID
detailed listing:
executing program 0:
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
r1 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, &(0x7f0000000240)=@pppol2tpin6={0x18, 0x1, {0x0, r1, 0x8, 0x0, 0x0, 0x0, {0xa, 0x0, 0x0, @rand_addr=' \x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02'}}}, 0x32)
sendfile(0xffffffffffffffff, 0xffffffffffffffff, &(0x7f0000000040)=0x3, 0xac5)
ioctl$EXT4_IOC_GETFSUUID(0xffffffffffffffff, 0x80047453, 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: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}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-syz_clone3-ioctl$EXT4_IOC_GETFSUUID
detailed listing:
executing program 0:
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
r1 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, &(0x7f0000000240)=@pppol2tpin6={0x18, 0x1, {0x0, r1, 0x8, 0x0, 0x0, 0x0, {0xa, 0x0, 0x0, @rand_addr=' \x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02'}}}, 0x32)
syz_clone3(&(0x7f0000000900)={0x23800000, &(0x7f0000000040)=<r2=>0xffffffffffffffff, 0x0, 0x0, {0x27}, 0x0, 0x0, 0x0, 0x0}, 0x58)
ioctl$EXT4_IOC_GETFSUUID(r2, 0x80047453, 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: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}}): socket$pppl2tp-socket$inet6_udp-sendfile-syz_clone3-ioctl$EXT4_IOC_GETFSUUID
detailed listing:
executing program 0:
socket$pppl2tp(0x18, 0x1, 0x1)
socket$inet6_udp(0xa, 0x2, 0x0)
sendfile(0xffffffffffffffff, 0xffffffffffffffff, &(0x7f0000000040)=0x3, 0xac5)
syz_clone3(&(0x7f0000000900)={0x23800000, &(0x7f0000000040)=<r0=>0xffffffffffffffff, 0x0, 0x0, {0x27}, 0x0, 0x0, 0x0, 0x0}, 0x58)
ioctl$EXT4_IOC_GETFSUUID(r0, 0x80047453, 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: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}}): socket$pppl2tp-connect$pppl2tp-sendfile-syz_clone3-ioctl$EXT4_IOC_GETFSUUID
detailed listing:
executing program 0:
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
connect$pppl2tp(r0, &(0x7f0000000240)=@pppol2tpin6={0x18, 0x1, {0x0, 0xffffffffffffffff, 0x8, 0x0, 0x0, 0x0, {0xa, 0x0, 0x0, @rand_addr=' \x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02'}}}, 0x32)
sendfile(0xffffffffffffffff, 0xffffffffffffffff, &(0x7f0000000040)=0x3, 0xac5)
syz_clone3(&(0x7f0000000900)={0x23800000, &(0x7f0000000040)=<r1=>0xffffffffffffffff, 0x0, 0x0, {0x27}, 0x0, 0x0, 0x0, 0x0}, 0x58)
ioctl$EXT4_IOC_GETFSUUID(r1, 0x80047453, 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: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}}): socket$inet6_udp-connect$pppl2tp-sendfile-syz_clone3-ioctl$EXT4_IOC_GETFSUUID
detailed listing:
executing program 0:
r0 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(0xffffffffffffffff, &(0x7f0000000240)=@pppol2tpin6={0x18, 0x1, {0x0, r0, 0x8, 0x0, 0x0, 0x0, {0xa, 0x0, 0x0, @rand_addr=' \x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02'}}}, 0x32)
sendfile(0xffffffffffffffff, 0xffffffffffffffff, &(0x7f0000000040)=0x3, 0xac5)
syz_clone3(&(0x7f0000000900)={0x23800000, &(0x7f0000000040)=<r1=>0xffffffffffffffff, 0x0, 0x0, {0x27}, 0x0, 0x0, 0x0, 0x0}, 0x58)
ioctl$EXT4_IOC_GETFSUUID(r1, 0x80047453, 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: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}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-sendfile-syz_clone3-ioctl$EXT4_IOC_GETFSUUID
detailed listing:
executing program 0:
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, 0x0, 0x0)
sendfile(0xffffffffffffffff, 0xffffffffffffffff, &(0x7f0000000040)=0x3, 0xac5)
syz_clone3(&(0x7f0000000900)={0x23800000, &(0x7f0000000040)=<r1=>0xffffffffffffffff, 0x0, 0x0, {0x27}, 0x0, 0x0, 0x0, 0x0}, 0x58)
ioctl$EXT4_IOC_GETFSUUID(r1, 0x80047453, 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: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}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-sendfile-syz_clone3-ioctl$EXT4_IOC_GETFSUUID
detailed listing:
executing program 0:
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
r1 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, &(0x7f0000000240)=@pppol2tpin6={0x18, 0x1, {0x0, r1, 0x8, 0x0, 0x0, 0x0, {0xa, 0x0, 0x0, @rand_addr=' \x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02'}}}, 0x32)
sendfile(0xffffffffffffffff, 0xffffffffffffffff, 0x0, 0xac5)
syz_clone3(&(0x7f0000000900)={0x23800000, &(0x7f0000000040)=<r2=>0xffffffffffffffff, 0x0, 0x0, {0x27}, 0x0, 0x0, 0x0, 0x0}, 0x58)
ioctl$EXT4_IOC_GETFSUUID(r2, 0x80047453, 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: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}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-sendfile-syz_clone3-ioctl$EXT4_IOC_GETFSUUID
detailed listing:
executing program 0:
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
r1 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, &(0x7f0000000240)=@pppol2tpin6={0x18, 0x1, {0x0, r1, 0x8, 0x0, 0x0, 0x0, {0xa, 0x0, 0x0, @rand_addr=' \x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02'}}}, 0x32)
sendfile(0xffffffffffffffff, 0xffffffffffffffff, &(0x7f0000000040)=0x3, 0xac5)
syz_clone3(0x0, 0x0)
ioctl$EXT4_IOC_GETFSUUID(0xffffffffffffffff, 0x80047453, 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: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}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-sendfile-syz_clone3-ioctl$EXT4_IOC_GETFSUUID
detailed listing:
executing program 0:
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
r1 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, &(0x7f0000000240)=@pppol2tpin6={0x18, 0x1, {0x0, r1, 0x8, 0x0, 0x0, 0x0, {0xa, 0x0, 0x0, @rand_addr=' \x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02'}}}, 0x32)
sendfile(0xffffffffffffffff, 0xffffffffffffffff, &(0x7f0000000040)=0x3, 0xac5)
syz_clone3(&(0x7f0000000900)={0x23800000, 0x0, 0x0, 0x0, {0x27}, 0x0, 0x0, 0x0, 0x0}, 0x58)
ioctl$EXT4_IOC_GETFSUUID(0xffffffffffffffff, 0x80047453, 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: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}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-sendfile-syz_clone3-ioctl$EXT4_IOC_GETFSUUID
program crashed: KASAN: use-after-free Read in pppol2tp_sock_to_session
a never seen crash title: KASAN: use-after-free Read in pppol2tp_sock_to_session, ignore
simplifying guilty program options
testing 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: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}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-sendfile-syz_clone3-ioctl$EXT4_IOC_GETFSUUID
detailed listing:
executing program 0:
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
r1 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, &(0x7f0000000240)=@pppol2tpin6={0x18, 0x1, {0x0, r1, 0x8, 0x0, 0x0, 0x0, {0xa, 0x0, 0x0, @rand_addr=' \x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02'}}}, 0x32)
sendfile(0xffffffffffffffff, 0xffffffffffffffff, &(0x7f0000000040)=0x3, 0xac5)
syz_clone3(&(0x7f0000000900)={0x23800000, &(0x7f0000000040)=<r2=>0xffffffffffffffff, 0x0, 0x0, {0x27}, 0x0, 0x0, 0x0, 0x0}, 0x58)
ioctl$EXT4_IOC_GETFSUUID(r2, 0x80047453, 0x0)

program crashed: KASAN: use-after-free Read in pppol2tp_sock_to_session
a never seen crash title: KASAN: use-after-free Read in pppol2tp_sock_to_session, ignore
testing program (duration=30s, {Threaded:true 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: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}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-sendfile-syz_clone3-ioctl$EXT4_IOC_GETFSUUID
detailed listing:
executing program 0:
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
r1 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, &(0x7f0000000240)=@pppol2tpin6={0x18, 0x1, {0x0, r1, 0x8, 0x0, 0x0, 0x0, {0xa, 0x0, 0x0, @rand_addr=' \x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02'}}}, 0x32)
sendfile(0xffffffffffffffff, 0xffffffffffffffff, &(0x7f0000000040)=0x3, 0xac5)
syz_clone3(&(0x7f0000000900)={0x23800000, &(0x7f0000000040)=<r2=>0xffffffffffffffff, 0x0, 0x0, {0x27}, 0x0, 0x0, 0x0, 0x0}, 0x58)
ioctl$EXT4_IOC_GETFSUUID(r2, 0x80047453, 0x0)

program did not crash
testing program (duration=30s, {Threaded:true 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: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}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-sendfile-syz_clone3-ioctl$EXT4_IOC_GETFSUUID
detailed listing:
executing program 0:
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
r1 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, &(0x7f0000000240)=@pppol2tpin6={0x18, 0x1, {0x0, r1, 0x8, 0x0, 0x0, 0x0, {0xa, 0x0, 0x0, @rand_addr=' \x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02'}}}, 0x32)
sendfile(0xffffffffffffffff, 0xffffffffffffffff, &(0x7f0000000040)=0x3, 0xac5)
syz_clone3(&(0x7f0000000900)={0x23800000, &(0x7f0000000040)=<r2=>0xffffffffffffffff, 0x0, 0x0, {0x27}, 0x0, 0x0, 0x0, 0x0}, 0x58)
ioctl$EXT4_IOC_GETFSUUID(r2, 0x80047453, 0x0)

program crashed: KASAN: use-after-free Read in pppol2tp_sock_to_session
a never seen crash title: KASAN: use-after-free Read in pppol2tp_sock_to_session, ignore
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: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}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-sendfile-syz_clone3-ioctl$EXT4_IOC_GETFSUUID
detailed listing:
executing program 0:
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
r1 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, &(0x7f0000000240)=@pppol2tpin6={0x18, 0x1, {0x0, r1, 0x8, 0x0, 0x0, 0x0, {0xa, 0x0, 0x0, @rand_addr=' \x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02'}}}, 0x32)
sendfile(0xffffffffffffffff, 0xffffffffffffffff, &(0x7f0000000040)=0x3, 0xac5)
syz_clone3(&(0x7f0000000900)={0x23800000, &(0x7f0000000040)=<r2=>0xffffffffffffffff, 0x0, 0x0, {0x27}, 0x0, 0x0, 0x0, 0x0}, 0x58)
ioctl$EXT4_IOC_GETFSUUID(r2, 0x80047453, 0x0)

program crashed: KASAN: use-after-free Read in pppol2tp_sock_to_session
validation run: crashed=true
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: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}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-sendfile-syz_clone3-ioctl$EXT4_IOC_GETFSUUID
detailed listing:
executing program 0:
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
r1 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, &(0x7f0000000240)=@pppol2tpin6={0x18, 0x1, {0x0, r1, 0x8, 0x0, 0x0, 0x0, {0xa, 0x0, 0x0, @rand_addr=' \x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02'}}}, 0x32)
sendfile(0xffffffffffffffff, 0xffffffffffffffff, &(0x7f0000000040)=0x3, 0xac5)
syz_clone3(&(0x7f0000000900)={0x23800000, &(0x7f0000000040)=<r2=>0xffffffffffffffff, 0x0, 0x0, {0x27}, 0x0, 0x0, 0x0, 0x0}, 0x58)
ioctl$EXT4_IOC_GETFSUUID(r2, 0x80047453, 0x0)

program crashed: KASAN: use-after-free Read in pppol2tp_sock_to_session
validation run: crashed=true
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: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}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-sendfile-syz_clone3-ioctl$EXT4_IOC_GETFSUUID
detailed listing:
executing program 0:
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
r1 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, &(0x7f0000000240)=@pppol2tpin6={0x18, 0x1, {0x0, r1, 0x8, 0x0, 0x0, 0x0, {0xa, 0x0, 0x0, @rand_addr=' \x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02'}}}, 0x32)
sendfile(0xffffffffffffffff, 0xffffffffffffffff, &(0x7f0000000040)=0x3, 0xac5)
syz_clone3(&(0x7f0000000900)={0x23800000, &(0x7f0000000040)=<r2=>0xffffffffffffffff, 0x0, 0x0, {0x27}, 0x0, 0x0, 0x0, 0x0}, 0x58)
ioctl$EXT4_IOC_GETFSUUID(r2, 0x80047453, 0x0)

program crashed: KASAN: use-after-free Read in rcu_cblist_dequeue
validation run: crashed=true
reproducing took 12m28.138718584s
repro crashed as (corrupted=false):
==================================================================
BUG: KASAN: use-after-free in rcu_cblist_dequeue+0x6c/0xb0 kernel/rcu/rcu_segcblist.c:75
Read of size 8 at addr ffff88812c964590 by task kworker/0:0/6

CPU: 0 PID: 6 Comm: kworker/0:0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
 <IRQ>
 __dump_stack+0x21/0x24 lib/dump_stack.c:88
 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106
 print_address_description+0x71/0x200 mm/kasan/report.c:316
 print_report+0x4a/0x60 mm/kasan/report.c:420
 kasan_report+0x122/0x150 mm/kasan/report.c:524
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:351
 rcu_cblist_dequeue+0x6c/0xb0 kernel/rcu/rcu_segcblist.c:75
 rcu_do_batch+0x4bc/0xc30 kernel/rcu/tree.c:2285
 rcu_core+0x486/0xf00 kernel/rcu/tree.c:2557
 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2574
 handle_softirqs+0x1d7/0x600 kernel/softirq.c:642
 __do_softirq kernel/softirq.c:680 [inline]
 invoke_softirq kernel/softirq.c:497 [inline]
 __irq_exit_rcu+0x52/0xf0 kernel/softirq.c:729
 irq_exit_rcu+0x9/0x10 kernel/softirq.c:741
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa9/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:find_stack lib/stackdepot.c:303 [inline]
RIP: 0010:__stack_depot_save+0x171/0x490 lib/stackdepot.c:452
Code: c1 c7 04 29 fe 31 f2 c1 c6 0e 29 f2 41 31 d7 c1 c2 18 41 29 d7 4c 8b 15 95 5c 2e 05 44 8b 25 8a 5c 2e 05 45 21 fc 4f 8b 2c e2 <4d> 85 ed 74 62 89 ca eb 09 4d 8b 6d 00 4d 85 ed 74 55 45 39 7d 08
RSP: 0018:ffffc900000674c0 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000000000000d
RDX: 0000000013569e02 RSI: 0000000091795c51 RDI: 000000000c8bc4c2
RBP: ffffc90000067520 R08: 0000000000000a20 R09: 0000000000000001
R10: ffff8881f5a00000 R11: 000000008b98d404 R12: 000000000000205d
R13: ffff88811d7a2f50 R14: ffffc90000067530 R15: 000000006300205d
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_set_track+0x60/0x70 mm/kasan/common.c:53
 kasan_save_alloc_info+0x1f/0x30 mm/kasan/generic.c:505
 __kasan_slab_alloc+0x72/0x80 mm/kasan/common.c:334
 kasan_slab_alloc include/linux/kasan.h:202 [inline]
 slab_post_alloc_hook+0x4f/0x2d0 mm/slab.h:768
 slab_alloc_node mm/slub.c:3382 [inline]
 kmem_cache_alloc_node+0x179/0x330 mm/slub.c:3429
 __alloc_skb+0xe8/0x4a0 net/core/skbuff.c:508
 alloc_skb include/linux/skbuff.h:1322 [inline]
 nlmsg_new include/net/netlink.h:987 [inline]
 inet6_ifa_notify net/ipv6/addrconf.c:5569 [inline]
 __ipv6_ifa_notify+0x200/0xe80 net/ipv6/addrconf.c:6227
 ipv6_ifa_notify net/ipv6/addrconf.c:6279 [inline]
 addrconf_dad_completed+0x192/0xe80 net/ipv6/addrconf.c:4283
 addrconf_dad_work+0xc1b/0x14a0 net/ipv6/addrconf.c:-1
 process_one_work+0x717/0xc30 kernel/workqueue.c:2302
 worker_thread+0xa4d/0x11d0 kernel/workqueue.c:2449
 kthread+0x281/0x320 kernel/kthread.c:386
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Allocated by task 397:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 kasan_save_alloc_info+0x1f/0x30 mm/kasan/generic.c:505
 ____kasan_kmalloc mm/kasan/common.c:380 [inline]
 __kasan_kmalloc+0x95/0xb0 mm/kasan/common.c:389
 kasan_kmalloc include/linux/kasan.h:212 [inline]
 __do_kmalloc_node mm/slab_common.c:938 [inline]
 __kmalloc+0xb4/0x1e0 mm/slab_common.c:951
 kmalloc include/linux/slab.h:568 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 l2tp_session_create+0x38/0xbd0 net/l2tp/l2tp_core.c:1614
 pppol2tp_connect+0xbf5/0x1640 net/l2tp/l2tp_ppp.c:771
 __sys_connect_file net/socket.c:2001 [inline]
 __sys_connect+0x3da/0x460 net/socket.c:2018
 __do_sys_connect net/socket.c:2028 [inline]
 __se_sys_connect net/socket.c:2025 [inline]
 __x64_sys_connect+0x7a/0x90 net/socket.c:2025
 x64_sys_call+0x88d/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:43
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Freed by task 405:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0x132/0x180 mm/kasan/common.c:242
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:250
 kasan_slab_free include/linux/kasan.h:178 [inline]
 slab_free_hook mm/slub.c:1750 [inline]
 slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1776
 slab_free mm/slub.c:3712 [inline]
 __kmem_cache_free+0xb7/0x1b0 mm/slub.c:3728
 kfree+0x6f/0xf0 mm/slab_common.c:990
 l2tp_session_free net/l2tp/l2tp_core.c:168 [inline]
 l2tp_session_put+0xaf/0x1a0 net/l2tp/l2tp_core.c:193
 l2tp_session_delete+0x3df/0x4d0 net/l2tp/l2tp_core.c:1587
 l2tp_tunnel_closeall net/l2tp/l2tp_core.c:1233 [inline]
 l2tp_tunnel_del_work+0x199/0x410 net/l2tp/l2tp_core.c:1271
 process_one_work+0x717/0xc30 kernel/workqueue.c:2302
 worker_thread+0xa4d/0x11d0 kernel/workqueue.c:2449
 kthread+0x281/0x320 kernel/kthread.c:386
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Last potentially related work creation:
 kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46
 __kasan_record_aux_stack+0xb6/0xc0 mm/kasan/generic.c:486
 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:496
 __call_rcu_common kernel/rcu/tree.c:2807 [inline]
 call_rcu+0xcf/0xf50 kernel/rcu/tree.c:2926
 pppol2tp_release+0x1e3/0x2b0 net/l2tp/l2tp_ppp.c:446
 __sock_release net/socket.c:652 [inline]
 sock_close+0xc9/0x220 net/socket.c:1390
 __fput+0x1fd/0x8f0 fs/file_table.c:320
 ____fput+0x15/0x20 fs/file_table.c:348
 task_work_run+0x1e1/0x250 kernel/task_work.c:203
 exit_task_work include/linux/task_work.h:39 [inline]
 do_exit+0xb0d/0x29f0 kernel/exit.c:896
 __do_sys_exit kernel/exit.c:1006 [inline]
 __se_sys_exit kernel/exit.c:1004 [inline]
 __cfi___ia32_sys_exit+0x0/0x10 kernel/exit.c:1004
 x64_sys_call+0x67/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:61
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

The buggy address belongs to the object at ffff88812c964400
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 400 bytes inside of
 512-byte region [ffff88812c964400, ffff88812c964600)

The buggy address belongs to the physical page:
page:ffffea0004b25900 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12c964
head:ffffea0004b25900 order:2 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head|zone=1)
raw: 4000000000010200 0000000000000000 dead000000000122 ffff888100042f00
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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 374, tgid 374 (syz-executor), ts 28861066735, free_ts 27095937487
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2673
 prep_new_page+0x1c/0x110 mm/page_alloc.c:2680
 get_page_from_freelist+0x2ca9/0x2d20 mm/page_alloc.c:4587
 __alloc_pages+0x1fa/0x610 mm/page_alloc.c:5931
 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1
 allocate_slab mm/slub.c:1967 [inline]
 new_slab+0x98/0x3e0 mm/slub.c:2020
 ___slab_alloc+0x70f/0xb70 mm/slub.c:3177
 __slab_alloc+0x5e/0xa0 mm/slub.c:3263
 slab_alloc_node mm/slub.c:3348 [inline]
 __kmem_cache_alloc_node+0x204/0x2d0 mm/slub.c:3423
 __do_kmalloc_node mm/slab_common.c:937 [inline]
 __kmalloc+0xa4/0x1e0 mm/slab_common.c:951
 kmalloc include/linux/slab.h:568 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 fib6_info_alloc+0x34/0xe0 net/ipv6/ip6_fib.c:156
 ip6_route_info_create+0x51b/0x14d0 net/ipv6/route.c:3799
 ip6_route_add+0x27/0x130 net/ipv6/route.c:3895
 addrconf_add_mroute net/ipv6/addrconf.c:2530 [inline]
 addrconf_add_dev+0x388/0x4a0 net/ipv6/addrconf.c:2548
 addrconf_dev_config net/ipv6/addrconf.c:3450 [inline]
 addrconf_init_auto_addrs+0x7b9/0xbc0 net/ipv6/addrconf.c:3538
 addrconf_notify+0x7fe/0xe30 net/ipv6/addrconf.c:3711
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 free_pages_prepare mm/page_alloc.c:1581 [inline]
 free_pcp_prepare mm/page_alloc.c:1655 [inline]
 free_unref_page_prepare+0x81b/0x820 mm/page_alloc.c:3622
 free_unref_page+0x93/0x530 mm/page_alloc.c:3720
 free_the_page mm/page_alloc.c:863 [inline]
 __free_pages+0x67/0x100 mm/page_alloc.c:6021
 __vunmap+0xa3c/0xc00 mm/vmalloc.c:2739
 __vfree mm/vmalloc.c:2788 [inline]
 vfree+0x61/0x90 mm/vmalloc.c:2819
 kcov_put kernel/kcov.c:437 [inline]
 kcov_close+0x2b/0x50 kernel/kcov.c:533
 __fput+0x1fd/0x8f0 fs/file_table.c:320
 ____fput+0x15/0x20 fs/file_table.c:348
 task_work_run+0x1e1/0x250 kernel/task_work.c:203
 exit_task_work include/linux/task_work.h:39 [inline]
 do_exit+0xb0d/0x29f0 kernel/exit.c:896
 do_group_exit+0x21b/0x2e0 kernel/exit.c:1040
 get_signal+0x167c/0x1700 kernel/signal.c:2904
 arch_do_signal_or_restart+0xd1/0x11c0 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x7a/0xb0 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:303

Memory state around the buggy address:
 ffff88812c964480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88812c964500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88812c964580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff88812c964600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88812c964680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
----------------
Code disassembly (best guess):
   0:	c1 c7 04             	rol    $0x4,%edi
   3:	29 fe                	sub    %edi,%esi
   5:	31 f2                	xor    %esi,%edx
   7:	c1 c6 0e             	rol    $0xe,%esi
   a:	29 f2                	sub    %esi,%edx
   c:	41 31 d7             	xor    %edx,%r15d
   f:	c1 c2 18             	rol    $0x18,%edx
  12:	41 29 d7             	sub    %edx,%r15d
  15:	4c 8b 15 95 5c 2e 05 	mov    0x52e5c95(%rip),%r10        # 0x52e5cb1
  1c:	44 8b 25 8a 5c 2e 05 	mov    0x52e5c8a(%rip),%r12d        # 0x52e5cad
  23:	45 21 fc             	and    %r15d,%r12d
  26:	4f 8b 2c e2          	mov    (%r10,%r12,8),%r13
* 2a:	4d 85 ed             	test   %r13,%r13 <-- trapping instruction
  2d:	74 62                	je     0x91
  2f:	89 ca                	mov    %ecx,%edx
  31:	eb 09                	jmp    0x3c
  33:	4d 8b 6d 00          	mov    0x0(%r13),%r13
  37:	4d 85 ed             	test   %r13,%r13
  3a:	74 55                	je     0x91
  3c:	45 39 7d 08          	cmp    %r15d,0x8(%r13)

final repro crashed as (corrupted=false):
==================================================================
BUG: KASAN: use-after-free in rcu_cblist_dequeue+0x6c/0xb0 kernel/rcu/rcu_segcblist.c:75
Read of size 8 at addr ffff88812c964590 by task kworker/0:0/6

CPU: 0 PID: 6 Comm: kworker/0:0 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
 <IRQ>
 __dump_stack+0x21/0x24 lib/dump_stack.c:88
 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106
 print_address_description+0x71/0x200 mm/kasan/report.c:316
 print_report+0x4a/0x60 mm/kasan/report.c:420
 kasan_report+0x122/0x150 mm/kasan/report.c:524
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:351
 rcu_cblist_dequeue+0x6c/0xb0 kernel/rcu/rcu_segcblist.c:75
 rcu_do_batch+0x4bc/0xc30 kernel/rcu/tree.c:2285
 rcu_core+0x486/0xf00 kernel/rcu/tree.c:2557
 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2574
 handle_softirqs+0x1d7/0x600 kernel/softirq.c:642
 __do_softirq kernel/softirq.c:680 [inline]
 invoke_softirq kernel/softirq.c:497 [inline]
 __irq_exit_rcu+0x52/0xf0 kernel/softirq.c:729
 irq_exit_rcu+0x9/0x10 kernel/softirq.c:741
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline]
 sysvec_apic_timer_interrupt+0xa9/0xc0 arch/x86/kernel/apic/apic.c:1118
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1b/0x20 arch/x86/include/asm/idtentry.h:691
RIP: 0010:find_stack lib/stackdepot.c:303 [inline]
RIP: 0010:__stack_depot_save+0x171/0x490 lib/stackdepot.c:452
Code: c1 c7 04 29 fe 31 f2 c1 c6 0e 29 f2 41 31 d7 c1 c2 18 41 29 d7 4c 8b 15 95 5c 2e 05 44 8b 25 8a 5c 2e 05 45 21 fc 4f 8b 2c e2 <4d> 85 ed 74 62 89 ca eb 09 4d 8b 6d 00 4d 85 ed 74 55 45 39 7d 08
RSP: 0018:ffffc900000674c0 EFLAGS: 00000202
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000000000000d
RDX: 0000000013569e02 RSI: 0000000091795c51 RDI: 000000000c8bc4c2
RBP: ffffc90000067520 R08: 0000000000000a20 R09: 0000000000000001
R10: ffff8881f5a00000 R11: 000000008b98d404 R12: 000000000000205d
R13: ffff88811d7a2f50 R14: ffffc90000067530 R15: 000000006300205d
 kasan_save_stack mm/kasan/common.c:47 [inline]
 kasan_set_track+0x60/0x70 mm/kasan/common.c:53
 kasan_save_alloc_info+0x1f/0x30 mm/kasan/generic.c:505
 __kasan_slab_alloc+0x72/0x80 mm/kasan/common.c:334
 kasan_slab_alloc include/linux/kasan.h:202 [inline]
 slab_post_alloc_hook+0x4f/0x2d0 mm/slab.h:768
 slab_alloc_node mm/slub.c:3382 [inline]
 kmem_cache_alloc_node+0x179/0x330 mm/slub.c:3429
 __alloc_skb+0xe8/0x4a0 net/core/skbuff.c:508
 alloc_skb include/linux/skbuff.h:1322 [inline]
 nlmsg_new include/net/netlink.h:987 [inline]
 inet6_ifa_notify net/ipv6/addrconf.c:5569 [inline]
 __ipv6_ifa_notify+0x200/0xe80 net/ipv6/addrconf.c:6227
 ipv6_ifa_notify net/ipv6/addrconf.c:6279 [inline]
 addrconf_dad_completed+0x192/0xe80 net/ipv6/addrconf.c:4283
 addrconf_dad_work+0xc1b/0x14a0 net/ipv6/addrconf.c:-1
 process_one_work+0x717/0xc30 kernel/workqueue.c:2302
 worker_thread+0xa4d/0x11d0 kernel/workqueue.c:2449
 kthread+0x281/0x320 kernel/kthread.c:386
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Allocated by task 397:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 kasan_save_alloc_info+0x1f/0x30 mm/kasan/generic.c:505
 ____kasan_kmalloc mm/kasan/common.c:380 [inline]
 __kasan_kmalloc+0x95/0xb0 mm/kasan/common.c:389
 kasan_kmalloc include/linux/kasan.h:212 [inline]
 __do_kmalloc_node mm/slab_common.c:938 [inline]
 __kmalloc+0xb4/0x1e0 mm/slab_common.c:951
 kmalloc include/linux/slab.h:568 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 l2tp_session_create+0x38/0xbd0 net/l2tp/l2tp_core.c:1614
 pppol2tp_connect+0xbf5/0x1640 net/l2tp/l2tp_ppp.c:771
 __sys_connect_file net/socket.c:2001 [inline]
 __sys_connect+0x3da/0x460 net/socket.c:2018
 __do_sys_connect net/socket.c:2028 [inline]
 __se_sys_connect net/socket.c:2025 [inline]
 __x64_sys_connect+0x7a/0x90 net/socket.c:2025
 x64_sys_call+0x88d/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:43
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Freed by task 405:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0x132/0x180 mm/kasan/common.c:242
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:250
 kasan_slab_free include/linux/kasan.h:178 [inline]
 slab_free_hook mm/slub.c:1750 [inline]
 slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1776
 slab_free mm/slub.c:3712 [inline]
 __kmem_cache_free+0xb7/0x1b0 mm/slub.c:3728
 kfree+0x6f/0xf0 mm/slab_common.c:990
 l2tp_session_free net/l2tp/l2tp_core.c:168 [inline]
 l2tp_session_put+0xaf/0x1a0 net/l2tp/l2tp_core.c:193
 l2tp_session_delete+0x3df/0x4d0 net/l2tp/l2tp_core.c:1587
 l2tp_tunnel_closeall net/l2tp/l2tp_core.c:1233 [inline]
 l2tp_tunnel_del_work+0x199/0x410 net/l2tp/l2tp_core.c:1271
 process_one_work+0x717/0xc30 kernel/workqueue.c:2302
 worker_thread+0xa4d/0x11d0 kernel/workqueue.c:2449
 kthread+0x281/0x320 kernel/kthread.c:386
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Last potentially related work creation:
 kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46
 __kasan_record_aux_stack+0xb6/0xc0 mm/kasan/generic.c:486
 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:496
 __call_rcu_common kernel/rcu/tree.c:2807 [inline]
 call_rcu+0xcf/0xf50 kernel/rcu/tree.c:2926
 pppol2tp_release+0x1e3/0x2b0 net/l2tp/l2tp_ppp.c:446
 __sock_release net/socket.c:652 [inline]
 sock_close+0xc9/0x220 net/socket.c:1390
 __fput+0x1fd/0x8f0 fs/file_table.c:320
 ____fput+0x15/0x20 fs/file_table.c:348
 task_work_run+0x1e1/0x250 kernel/task_work.c:203
 exit_task_work include/linux/task_work.h:39 [inline]
 do_exit+0xb0d/0x29f0 kernel/exit.c:896
 __do_sys_exit kernel/exit.c:1006 [inline]
 __se_sys_exit kernel/exit.c:1004 [inline]
 __cfi___ia32_sys_exit+0x0/0x10 kernel/exit.c:1004
 x64_sys_call+0x67/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:61
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

The buggy address belongs to the object at ffff88812c964400
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 400 bytes inside of
 512-byte region [ffff88812c964400, ffff88812c964600)

The buggy address belongs to the physical page:
page:ffffea0004b25900 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12c964
head:ffffea0004b25900 order:2 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head|zone=1)
raw: 4000000000010200 0000000000000000 dead000000000122 ffff888100042f00
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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 374, tgid 374 (syz-executor), ts 28861066735, free_ts 27095937487
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2673
 prep_new_page+0x1c/0x110 mm/page_alloc.c:2680
 get_page_from_freelist+0x2ca9/0x2d20 mm/page_alloc.c:4587
 __alloc_pages+0x1fa/0x610 mm/page_alloc.c:5931
 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1
 allocate_slab mm/slub.c:1967 [inline]
 new_slab+0x98/0x3e0 mm/slub.c:2020
 ___slab_alloc+0x70f/0xb70 mm/slub.c:3177
 __slab_alloc+0x5e/0xa0 mm/slub.c:3263
 slab_alloc_node mm/slub.c:3348 [inline]
 __kmem_cache_alloc_node+0x204/0x2d0 mm/slub.c:3423
 __do_kmalloc_node mm/slab_common.c:937 [inline]
 __kmalloc+0xa4/0x1e0 mm/slab_common.c:951
 kmalloc include/linux/slab.h:568 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 fib6_info_alloc+0x34/0xe0 net/ipv6/ip6_fib.c:156
 ip6_route_info_create+0x51b/0x14d0 net/ipv6/route.c:3799
 ip6_route_add+0x27/0x130 net/ipv6/route.c:3895
 addrconf_add_mroute net/ipv6/addrconf.c:2530 [inline]
 addrconf_add_dev+0x388/0x4a0 net/ipv6/addrconf.c:2548
 addrconf_dev_config net/ipv6/addrconf.c:3450 [inline]
 addrconf_init_auto_addrs+0x7b9/0xbc0 net/ipv6/addrconf.c:3538
 addrconf_notify+0x7fe/0xe30 net/ipv6/addrconf.c:3711
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 free_pages_prepare mm/page_alloc.c:1581 [inline]
 free_pcp_prepare mm/page_alloc.c:1655 [inline]
 free_unref_page_prepare+0x81b/0x820 mm/page_alloc.c:3622
 free_unref_page+0x93/0x530 mm/page_alloc.c:3720
 free_the_page mm/page_alloc.c:863 [inline]
 __free_pages+0x67/0x100 mm/page_alloc.c:6021
 __vunmap+0xa3c/0xc00 mm/vmalloc.c:2739
 __vfree mm/vmalloc.c:2788 [inline]
 vfree+0x61/0x90 mm/vmalloc.c:2819
 kcov_put kernel/kcov.c:437 [inline]
 kcov_close+0x2b/0x50 kernel/kcov.c:533
 __fput+0x1fd/0x8f0 fs/file_table.c:320
 ____fput+0x15/0x20 fs/file_table.c:348
 task_work_run+0x1e1/0x250 kernel/task_work.c:203
 exit_task_work include/linux/task_work.h:39 [inline]
 do_exit+0xb0d/0x29f0 kernel/exit.c:896
 do_group_exit+0x21b/0x2e0 kernel/exit.c:1040
 get_signal+0x167c/0x1700 kernel/signal.c:2904
 arch_do_signal_or_restart+0xd1/0x11c0 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x7a/0xb0 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:303

Memory state around the buggy address:
 ffff88812c964480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88812c964500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88812c964580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff88812c964600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88812c964680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
----------------
Code disassembly (best guess):
   0:	c1 c7 04             	rol    $0x4,%edi
   3:	29 fe                	sub    %edi,%esi
   5:	31 f2                	xor    %esi,%edx
   7:	c1 c6 0e             	rol    $0xe,%esi
   a:	29 f2                	sub    %esi,%edx
   c:	41 31 d7             	xor    %edx,%r15d
   f:	c1 c2 18             	rol    $0x18,%edx
  12:	41 29 d7             	sub    %edx,%r15d
  15:	4c 8b 15 95 5c 2e 05 	mov    0x52e5c95(%rip),%r10        # 0x52e5cb1
  1c:	44 8b 25 8a 5c 2e 05 	mov    0x52e5c8a(%rip),%r12d        # 0x52e5cad
  23:	45 21 fc             	and    %r15d,%r12d
  26:	4f 8b 2c e2          	mov    (%r10,%r12,8),%r13
* 2a:	4d 85 ed             	test   %r13,%r13 <-- trapping instruction
  2d:	74 62                	je     0x91
  2f:	89 ca                	mov    %ecx,%edx
  31:	eb 09                	jmp    0x3c
  33:	4d 8b 6d 00          	mov    0x0(%r13),%r13
  37:	4d 85 ed             	test   %r13,%r13
  3a:	74 55                	je     0x91
  3c:	45 39 7d 08          	cmp    %r15d,0x8(%r13)