Extracting prog: 25.430165649s
Minimizing prog: 11m51.444858109s
Simplifying prog options: 0s
Extracting C: 46.863662369s
Simplifying C: 2m56.63958124s


extracting reproducer from 103 programs
testing a last program of every proc
single: executing 53 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$inet6_udp-openat$sysfs-write$FUSE_NOTIFY_STORE-socket$pppl2tp-openat$tun-ioctl$TUNSETIFF-ioctl$TUNATTACHFILTER-socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-listen-ioctl$XFS_IOC_FSGROWFSLOG-syz_genetlink_get_family_id$l2tp-socket$nl_generic-getsockopt$inet6_IPV6_FLOWLABEL_MGR-connect$pppl2tp
detailed listing:
executing program 0:
r0 = socket$inet6_udp(0xa, 0x2, 0x0)
r1 = openat$sysfs(0xffffffffffffff9c, &(0x7f0000000140)='/sys/kernel/rcu_normal', 0x80042, 0x12)
write$FUSE_NOTIFY_STORE(r1, &(0x7f00000002c0)=ANY=[@ANYBLOB='-', @ANYRESDEC], 0x28)
r2 = socket$pppl2tp(0x18, 0x1, 0x1)
r3 = openat$tun(0xffffffffffffff9c, &(0x7f0000000040), 0x20000, 0x0)
ioctl$TUNSETIFF(r3, 0x400454ca, &(0x7f0000000200)={'pimreg\x00', 0x112})
ioctl$TUNATTACHFILTER(r3, 0x400454d1, 0x0)
r4 = socket$pppl2tp(0x18, 0x1, 0x1)
r5 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r4, &(0x7f0000000000)=@pppol2tpv3={0x18, 0x1, {0x3, r5, {0x2, 0x0, @multicast2}, 0x2, 0x0, 0x4}}, 0x2e)
listen(r5, 0x78afa8bd)
ioctl$XFS_IOC_FSGROWFSLOG(r4, 0x4008586f, &(0x7f0000000180)={0x6, 0x8})
syz_genetlink_get_family_id$l2tp(&(0x7f0000000080), 0xffffffffffffffff)
socket$nl_generic(0x10, 0x3, 0x10)
getsockopt$inet6_IPV6_FLOWLABEL_MGR(r5, 0x29, 0x20, &(0x7f0000000040)={@rand_addr=' \x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01', 0x7f, 0x0, 0xff, 0xe, 0x6, 0x1000}, &(0x7f00000000c0)=0x20)
connect$pppl2tp(r2, &(0x7f0000000100)=@pppol2tpv3in6={0x18, 0x1, {0x20000000, r0, 0x21, 0x0, 0x3, 0x0, {0xa, 0x0, 0x6, @private0}}}, 0x3a)

program crashed: KASAN: use-after-free Write in pppol2tp_release
single: successfully extracted reproducer
found reproducer with 16 syscalls
minimizing guilty program
testing program (duration=32.773232646s, {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$inet6_udp-openat$sysfs-write$FUSE_NOTIFY_STORE-socket$pppl2tp-openat$tun-ioctl$TUNSETIFF-ioctl$TUNATTACHFILTER-socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-listen-ioctl$XFS_IOC_FSGROWFSLOG-syz_genetlink_get_family_id$l2tp-socket$nl_generic-getsockopt$inet6_IPV6_FLOWLABEL_MGR
detailed listing:
executing program 0:
socket$inet6_udp(0xa, 0x2, 0x0)
r0 = openat$sysfs(0xffffffffffffff9c, &(0x7f0000000140)='/sys/kernel/rcu_normal', 0x80042, 0x12)
write$FUSE_NOTIFY_STORE(r0, &(0x7f00000002c0)=ANY=[@ANYBLOB='-', @ANYRESDEC], 0x28)
socket$pppl2tp(0x18, 0x1, 0x1)
r1 = openat$tun(0xffffffffffffff9c, &(0x7f0000000040), 0x20000, 0x0)
ioctl$TUNSETIFF(r1, 0x400454ca, &(0x7f0000000200)={'pimreg\x00', 0x112})
ioctl$TUNATTACHFILTER(r1, 0x400454d1, 0x0)
r2 = socket$pppl2tp(0x18, 0x1, 0x1)
r3 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r2, &(0x7f0000000000)=@pppol2tpv3={0x18, 0x1, {0x3, r3, {0x2, 0x0, @multicast2}, 0x2, 0x0, 0x4}}, 0x2e)
listen(r3, 0x78afa8bd)
ioctl$XFS_IOC_FSGROWFSLOG(r2, 0x4008586f, &(0x7f0000000180)={0x6, 0x8})
syz_genetlink_get_family_id$l2tp(&(0x7f0000000080), 0xffffffffffffffff)
socket$nl_generic(0x10, 0x3, 0x10)
getsockopt$inet6_IPV6_FLOWLABEL_MGR(r3, 0x29, 0x20, &(0x7f0000000040)={@rand_addr=' \x01\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x01', 0x7f, 0x0, 0xff, 0xe, 0x6, 0x1000}, &(0x7f00000000c0)=0x20)

program crashed: KASAN: use-after-free Write in pppol2tp_release
testing program (duration=32.773232646s, {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$inet6_udp-openat$sysfs-write$FUSE_NOTIFY_STORE-socket$pppl2tp-openat$tun-ioctl$TUNSETIFF-ioctl$TUNATTACHFILTER-socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-listen-ioctl$XFS_IOC_FSGROWFSLOG-syz_genetlink_get_family_id$l2tp-socket$nl_generic
detailed listing:
executing program 0:
socket$inet6_udp(0xa, 0x2, 0x0)
r0 = openat$sysfs(0xffffffffffffff9c, &(0x7f0000000140)='/sys/kernel/rcu_normal', 0x80042, 0x12)
write$FUSE_NOTIFY_STORE(r0, &(0x7f00000002c0)=ANY=[@ANYBLOB='-', @ANYRESDEC], 0x28)
socket$pppl2tp(0x18, 0x1, 0x1)
r1 = openat$tun(0xffffffffffffff9c, &(0x7f0000000040), 0x20000, 0x0)
ioctl$TUNSETIFF(r1, 0x400454ca, &(0x7f0000000200)={'pimreg\x00', 0x112})
ioctl$TUNATTACHFILTER(r1, 0x400454d1, 0x0)
r2 = socket$pppl2tp(0x18, 0x1, 0x1)
r3 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r2, &(0x7f0000000000)=@pppol2tpv3={0x18, 0x1, {0x3, r3, {0x2, 0x0, @multicast2}, 0x2, 0x0, 0x4}}, 0x2e)
listen(r3, 0x78afa8bd)
ioctl$XFS_IOC_FSGROWFSLOG(r2, 0x4008586f, &(0x7f0000000180)={0x6, 0x8})
syz_genetlink_get_family_id$l2tp(&(0x7f0000000080), 0xffffffffffffffff)
socket$nl_generic(0x10, 0x3, 0x10)

program crashed: KASAN: use-after-free Read in pppol2tp_sock_to_session
testing program (duration=32.773232646s, {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$inet6_udp-openat$sysfs-write$FUSE_NOTIFY_STORE-socket$pppl2tp-openat$tun-ioctl$TUNSETIFF-ioctl$TUNATTACHFILTER-socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-listen-ioctl$XFS_IOC_FSGROWFSLOG-syz_genetlink_get_family_id$l2tp
detailed listing:
executing program 0:
socket$inet6_udp(0xa, 0x2, 0x0)
r0 = openat$sysfs(0xffffffffffffff9c, &(0x7f0000000140)='/sys/kernel/rcu_normal', 0x80042, 0x12)
write$FUSE_NOTIFY_STORE(r0, &(0x7f00000002c0)=ANY=[@ANYBLOB='-', @ANYRESDEC], 0x28)
socket$pppl2tp(0x18, 0x1, 0x1)
r1 = openat$tun(0xffffffffffffff9c, &(0x7f0000000040), 0x20000, 0x0)
ioctl$TUNSETIFF(r1, 0x400454ca, &(0x7f0000000200)={'pimreg\x00', 0x112})
ioctl$TUNATTACHFILTER(r1, 0x400454d1, 0x0)
r2 = socket$pppl2tp(0x18, 0x1, 0x1)
r3 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r2, &(0x7f0000000000)=@pppol2tpv3={0x18, 0x1, {0x3, r3, {0x2, 0x0, @multicast2}, 0x2, 0x0, 0x4}}, 0x2e)
listen(r3, 0x78afa8bd)
ioctl$XFS_IOC_FSGROWFSLOG(r2, 0x4008586f, &(0x7f0000000180)={0x6, 0x8})
syz_genetlink_get_family_id$l2tp(&(0x7f0000000080), 0xffffffffffffffff)

program crashed: KASAN: use-after-free Write in rcu_segcblist_enqueue
testing program (duration=32.773232646s, {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$inet6_udp-openat$sysfs-write$FUSE_NOTIFY_STORE-socket$pppl2tp-openat$tun-ioctl$TUNSETIFF-ioctl$TUNATTACHFILTER-socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-listen-ioctl$XFS_IOC_FSGROWFSLOG
detailed listing:
executing program 0:
socket$inet6_udp(0xa, 0x2, 0x0)
r0 = openat$sysfs(0xffffffffffffff9c, &(0x7f0000000140)='/sys/kernel/rcu_normal', 0x80042, 0x12)
write$FUSE_NOTIFY_STORE(r0, &(0x7f00000002c0)=ANY=[@ANYBLOB='-', @ANYRESDEC], 0x28)
socket$pppl2tp(0x18, 0x1, 0x1)
r1 = openat$tun(0xffffffffffffff9c, &(0x7f0000000040), 0x20000, 0x0)
ioctl$TUNSETIFF(r1, 0x400454ca, &(0x7f0000000200)={'pimreg\x00', 0x112})
ioctl$TUNATTACHFILTER(r1, 0x400454d1, 0x0)
r2 = socket$pppl2tp(0x18, 0x1, 0x1)
r3 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r2, &(0x7f0000000000)=@pppol2tpv3={0x18, 0x1, {0x3, r3, {0x2, 0x0, @multicast2}, 0x2, 0x0, 0x4}}, 0x2e)
listen(r3, 0x78afa8bd)
ioctl$XFS_IOC_FSGROWFSLOG(r2, 0x4008586f, &(0x7f0000000180)={0x6, 0x8})

program crashed: KASAN: use-after-free Write in pppol2tp_release
testing program (duration=32.773232646s, {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$inet6_udp-openat$sysfs-write$FUSE_NOTIFY_STORE-socket$pppl2tp-openat$tun-ioctl$TUNSETIFF-ioctl$TUNATTACHFILTER-socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-listen
detailed listing:
executing program 0:
socket$inet6_udp(0xa, 0x2, 0x0)
r0 = openat$sysfs(0xffffffffffffff9c, &(0x7f0000000140)='/sys/kernel/rcu_normal', 0x80042, 0x12)
write$FUSE_NOTIFY_STORE(r0, &(0x7f00000002c0)=ANY=[@ANYBLOB='-', @ANYRESDEC], 0x28)
socket$pppl2tp(0x18, 0x1, 0x1)
r1 = openat$tun(0xffffffffffffff9c, &(0x7f0000000040), 0x20000, 0x0)
ioctl$TUNSETIFF(r1, 0x400454ca, &(0x7f0000000200)={'pimreg\x00', 0x112})
ioctl$TUNATTACHFILTER(r1, 0x400454d1, 0x0)
r2 = socket$pppl2tp(0x18, 0x1, 0x1)
r3 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r2, &(0x7f0000000000)=@pppol2tpv3={0x18, 0x1, {0x3, r3, {0x2, 0x0, @multicast2}, 0x2, 0x0, 0x4}}, 0x2e)
listen(r3, 0x78afa8bd)

program did not crash
testing program (duration=32.773232646s, {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$inet6_udp-openat$sysfs-write$FUSE_NOTIFY_STORE-socket$pppl2tp-openat$tun-ioctl$TUNSETIFF-ioctl$TUNATTACHFILTER-socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
detailed listing:
executing program 0:
socket$inet6_udp(0xa, 0x2, 0x0)
r0 = openat$sysfs(0xffffffffffffff9c, &(0x7f0000000140)='/sys/kernel/rcu_normal', 0x80042, 0x12)
write$FUSE_NOTIFY_STORE(r0, &(0x7f00000002c0)=ANY=[@ANYBLOB='-', @ANYRESDEC], 0x28)
socket$pppl2tp(0x18, 0x1, 0x1)
r1 = openat$tun(0xffffffffffffff9c, &(0x7f0000000040), 0x20000, 0x0)
ioctl$TUNSETIFF(r1, 0x400454ca, &(0x7f0000000200)={'pimreg\x00', 0x112})
ioctl$TUNATTACHFILTER(r1, 0x400454d1, 0x0)
r2 = socket$pppl2tp(0x18, 0x1, 0x1)
r3 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r2, &(0x7f0000000000)=@pppol2tpv3={0x18, 0x1, {0x3, r3, {0x2, 0x0, @multicast2}, 0x2, 0x0, 0x4}}, 0x2e)
ioctl$XFS_IOC_FSGROWFSLOG(r2, 0x4008586f, &(0x7f0000000180)={0x6, 0x8})

program crashed: KASAN: use-after-free Write in pppol2tp_release
testing program (duration=32.773232646s, {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$inet6_udp-openat$sysfs-write$FUSE_NOTIFY_STORE-socket$pppl2tp-openat$tun-ioctl$TUNSETIFF-ioctl$TUNATTACHFILTER-socket$pppl2tp-socket$inet6_udp-ioctl$XFS_IOC_FSGROWFSLOG
detailed listing:
executing program 0:
socket$inet6_udp(0xa, 0x2, 0x0)
r0 = openat$sysfs(0xffffffffffffff9c, &(0x7f0000000140)='/sys/kernel/rcu_normal', 0x80042, 0x12)
write$FUSE_NOTIFY_STORE(r0, &(0x7f00000002c0)=ANY=[@ANYBLOB='-', @ANYRESDEC], 0x28)
socket$pppl2tp(0x18, 0x1, 0x1)
r1 = openat$tun(0xffffffffffffff9c, &(0x7f0000000040), 0x20000, 0x0)
ioctl$TUNSETIFF(r1, 0x400454ca, &(0x7f0000000200)={'pimreg\x00', 0x112})
ioctl$TUNATTACHFILTER(r1, 0x400454d1, 0x0)
r2 = socket$pppl2tp(0x18, 0x1, 0x1)
socket$inet6_udp(0xa, 0x2, 0x0)
ioctl$XFS_IOC_FSGROWFSLOG(r2, 0x4008586f, &(0x7f0000000180)={0x6, 0x8})

program did not crash
testing program (duration=32.773232646s, {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$inet6_udp-openat$sysfs-write$FUSE_NOTIFY_STORE-socket$pppl2tp-openat$tun-ioctl$TUNSETIFF-ioctl$TUNATTACHFILTER-socket$pppl2tp-connect$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
detailed listing:
executing program 0:
socket$inet6_udp(0xa, 0x2, 0x0)
r0 = openat$sysfs(0xffffffffffffff9c, &(0x7f0000000140)='/sys/kernel/rcu_normal', 0x80042, 0x12)
write$FUSE_NOTIFY_STORE(r0, &(0x7f00000002c0)=ANY=[@ANYBLOB='-', @ANYRESDEC], 0x28)
socket$pppl2tp(0x18, 0x1, 0x1)
r1 = openat$tun(0xffffffffffffff9c, &(0x7f0000000040), 0x20000, 0x0)
ioctl$TUNSETIFF(r1, 0x400454ca, &(0x7f0000000200)={'pimreg\x00', 0x112})
ioctl$TUNATTACHFILTER(r1, 0x400454d1, 0x0)
r2 = socket$pppl2tp(0x18, 0x1, 0x1)
connect$pppl2tp(r2, &(0x7f0000000000)=@pppol2tpv3={0x18, 0x1, {0x3, 0xffffffffffffffff, {0x2, 0x0, @multicast2}, 0x2, 0x0, 0x4}}, 0x2e)
ioctl$XFS_IOC_FSGROWFSLOG(r2, 0x4008586f, &(0x7f0000000180)={0x6, 0x8})

program did not crash
testing program (duration=32.773232646s, {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$inet6_udp-openat$sysfs-write$FUSE_NOTIFY_STORE-socket$pppl2tp-openat$tun-ioctl$TUNSETIFF-ioctl$TUNATTACHFILTER-socket$inet6_udp-connect$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
detailed listing:
executing program 0:
socket$inet6_udp(0xa, 0x2, 0x0)
r0 = openat$sysfs(0xffffffffffffff9c, &(0x7f0000000140)='/sys/kernel/rcu_normal', 0x80042, 0x12)
write$FUSE_NOTIFY_STORE(r0, &(0x7f00000002c0)=ANY=[@ANYBLOB='-', @ANYRESDEC], 0x28)
socket$pppl2tp(0x18, 0x1, 0x1)
r1 = openat$tun(0xffffffffffffff9c, &(0x7f0000000040), 0x20000, 0x0)
ioctl$TUNSETIFF(r1, 0x400454ca, &(0x7f0000000200)={'pimreg\x00', 0x112})
ioctl$TUNATTACHFILTER(r1, 0x400454d1, 0x0)
r2 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(0xffffffffffffffff, &(0x7f0000000000)=@pppol2tpv3={0x18, 0x1, {0x3, r2, {0x2, 0x0, @multicast2}, 0x2, 0x0, 0x4}}, 0x2e)
ioctl$XFS_IOC_FSGROWFSLOG(0xffffffffffffffff, 0x4008586f, &(0x7f0000000180)={0x6, 0x8})

program did not crash
testing program (duration=32.773232646s, {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$inet6_udp-openat$sysfs-write$FUSE_NOTIFY_STORE-socket$pppl2tp-openat$tun-ioctl$TUNSETIFF-socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
detailed listing:
executing program 0:
socket$inet6_udp(0xa, 0x2, 0x0)
r0 = openat$sysfs(0xffffffffffffff9c, &(0x7f0000000140)='/sys/kernel/rcu_normal', 0x80042, 0x12)
write$FUSE_NOTIFY_STORE(r0, &(0x7f00000002c0)=ANY=[@ANYBLOB='-', @ANYRESDEC], 0x28)
socket$pppl2tp(0x18, 0x1, 0x1)
r1 = openat$tun(0xffffffffffffff9c, &(0x7f0000000040), 0x20000, 0x0)
ioctl$TUNSETIFF(r1, 0x400454ca, &(0x7f0000000200)={'pimreg\x00', 0x112})
r2 = socket$pppl2tp(0x18, 0x1, 0x1)
r3 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r2, &(0x7f0000000000)=@pppol2tpv3={0x18, 0x1, {0x3, r3, {0x2, 0x0, @multicast2}, 0x2, 0x0, 0x4}}, 0x2e)
ioctl$XFS_IOC_FSGROWFSLOG(r2, 0x4008586f, &(0x7f0000000180)={0x6, 0x8})

program crashed: KASAN: use-after-free Write in rcu_segcblist_enqueue
testing program (duration=32.773232646s, {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$inet6_udp-openat$sysfs-write$FUSE_NOTIFY_STORE-socket$pppl2tp-openat$tun-socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
detailed listing:
executing program 0:
socket$inet6_udp(0xa, 0x2, 0x0)
r0 = openat$sysfs(0xffffffffffffff9c, &(0x7f0000000140)='/sys/kernel/rcu_normal', 0x80042, 0x12)
write$FUSE_NOTIFY_STORE(r0, &(0x7f00000002c0)=ANY=[@ANYBLOB='-', @ANYRESDEC], 0x28)
socket$pppl2tp(0x18, 0x1, 0x1)
openat$tun(0xffffffffffffff9c, &(0x7f0000000040), 0x20000, 0x0)
r1 = socket$pppl2tp(0x18, 0x1, 0x1)
r2 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r1, &(0x7f0000000000)=@pppol2tpv3={0x18, 0x1, {0x3, r2, {0x2, 0x0, @multicast2}, 0x2, 0x0, 0x4}}, 0x2e)
ioctl$XFS_IOC_FSGROWFSLOG(r1, 0x4008586f, &(0x7f0000000180)={0x6, 0x8})

program crashed: KASAN: use-after-free Read in pppol2tp_sock_to_session
testing program (duration=32.773232646s, {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$inet6_udp-openat$sysfs-write$FUSE_NOTIFY_STORE-socket$pppl2tp-socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
detailed listing:
executing program 0:
socket$inet6_udp(0xa, 0x2, 0x0)
r0 = openat$sysfs(0xffffffffffffff9c, &(0x7f0000000140)='/sys/kernel/rcu_normal', 0x80042, 0x12)
write$FUSE_NOTIFY_STORE(r0, &(0x7f00000002c0)=ANY=[@ANYBLOB='-', @ANYRESDEC], 0x28)
socket$pppl2tp(0x18, 0x1, 0x1)
r1 = socket$pppl2tp(0x18, 0x1, 0x1)
r2 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r1, &(0x7f0000000000)=@pppol2tpv3={0x18, 0x1, {0x3, r2, {0x2, 0x0, @multicast2}, 0x2, 0x0, 0x4}}, 0x2e)
ioctl$XFS_IOC_FSGROWFSLOG(r1, 0x4008586f, &(0x7f0000000180)={0x6, 0x8})

program crashed: KASAN: use-after-free Write in pppol2tp_release
testing program (duration=32.773232646s, {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$inet6_udp-openat$sysfs-write$FUSE_NOTIFY_STORE-socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
detailed listing:
executing program 0:
socket$inet6_udp(0xa, 0x2, 0x0)
r0 = openat$sysfs(0xffffffffffffff9c, &(0x7f0000000140)='/sys/kernel/rcu_normal', 0x80042, 0x12)
write$FUSE_NOTIFY_STORE(r0, &(0x7f00000002c0)=ANY=[@ANYBLOB='-', @ANYRESDEC], 0x28)
r1 = socket$pppl2tp(0x18, 0x1, 0x1)
r2 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r1, &(0x7f0000000000)=@pppol2tpv3={0x18, 0x1, {0x3, r2, {0x2, 0x0, @multicast2}, 0x2, 0x0, 0x4}}, 0x2e)
ioctl$XFS_IOC_FSGROWFSLOG(r1, 0x4008586f, &(0x7f0000000180)={0x6, 0x8})

program crashed: KASAN: use-after-free Read in pppol2tp_sock_to_session
testing program (duration=32.773232646s, {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$inet6_udp-openat$sysfs-socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
detailed listing:
executing program 0:
socket$inet6_udp(0xa, 0x2, 0x0)
openat$sysfs(0xffffffffffffff9c, &(0x7f0000000140)='/sys/kernel/rcu_normal', 0x80042, 0x12)
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
r1 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, &(0x7f0000000000)=@pppol2tpv3={0x18, 0x1, {0x3, r1, {0x2, 0x0, @multicast2}, 0x2, 0x0, 0x4}}, 0x2e)
ioctl$XFS_IOC_FSGROWFSLOG(r0, 0x4008586f, &(0x7f0000000180)={0x6, 0x8})

program crashed: KASAN: use-after-free Write in rcu_segcblist_enqueue
testing program (duration=32.773232646s, {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$inet6_udp-socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
detailed listing:
executing program 0:
socket$inet6_udp(0xa, 0x2, 0x0)
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
r1 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, &(0x7f0000000000)=@pppol2tpv3={0x18, 0x1, {0x3, r1, {0x2, 0x0, @multicast2}, 0x2, 0x0, 0x4}}, 0x2e)
ioctl$XFS_IOC_FSGROWFSLOG(r0, 0x4008586f, &(0x7f0000000180)={0x6, 0x8})

program crashed: KASAN: use-after-free Write in pppol2tp_release
testing program (duration=32.773232646s, {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$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
detailed listing:
executing program 0:
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
r1 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, &(0x7f0000000000)=@pppol2tpv3={0x18, 0x1, {0x3, r1, {0x2, 0x0, @multicast2}, 0x2, 0x0, 0x4}}, 0x2e)
ioctl$XFS_IOC_FSGROWFSLOG(r0, 0x4008586f, &(0x7f0000000180)={0x6, 0x8})

program crashed: KASAN: use-after-free Read in pppol2tp_sock_to_session
testing program (duration=32.773232646s, {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$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
detailed listing:
executing program 0:
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, 0x0, 0x0)
ioctl$XFS_IOC_FSGROWFSLOG(r0, 0x4008586f, &(0x7f0000000180)={0x6, 0x8})

program did not crash
testing program (duration=32.773232646s, {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$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
detailed listing:
executing program 0:
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
r1 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, &(0x7f0000000000)=@pppol2tpv3={0x18, 0x1, {0x3, r1, {0x2, 0x0, @multicast2}, 0x2, 0x0, 0x4}}, 0x2e)
ioctl$XFS_IOC_FSGROWFSLOG(r0, 0x4008586f, 0x0)

program crashed: KASAN: use-after-free Read in pppol2tp_sock_to_session
extracting C reproducer
testing compiled C program (duration=32.773232646s, {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$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
program crashed: KASAN: use-after-free Write in pppol2tp_release
simplifying C reproducer
testing compiled C program (duration=32.773232646s, {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$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
program crashed: KASAN: use-after-free Write in pppol2tp_release
testing compiled C program (duration=32.773232646s, {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: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$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
program crashed: KASAN: use-after-free Write in pppol2tp_release
testing compiled C program (duration=32.773232646s, {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:false Sysctl:true Swap:false UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
program crashed: KASAN: use-after-free Read in pppol2tp_sock_to_session
testing compiled C program (duration=32.773232646s, {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:false Sysctl:true Swap:false UseTmpDir:false HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
program crashed: KASAN: use-after-free Read in pppol2tp_sock_to_session
testing compiled C program (duration=32.773232646s, {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:false Sysctl:true Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
program crashed: KASAN: use-after-free Write in pppol2tp_release
testing compiled C program (duration=32.773232646s, {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:false Sysctl:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
program did not crash
testing program (duration=32.773232646s, {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:false Sysctl:true Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
detailed listing:
executing program 0:
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
r1 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, &(0x7f0000000000)=@pppol2tpv3={0x18, 0x1, {0x3, r1, {0x2, 0x0, @multicast2}, 0x2, 0x0, 0x4}}, 0x2e)
ioctl$XFS_IOC_FSGROWFSLOG(r0, 0x4008586f, 0x0)

program crashed: KASAN: use-after-free Read in pppol2tp_sock_to_session
validation run: crashed=true
testing program (duration=32.773232646s, {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:false Sysctl:true Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
detailed listing:
executing program 0:
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
r1 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, &(0x7f0000000000)=@pppol2tpv3={0x18, 0x1, {0x3, r1, {0x2, 0x0, @multicast2}, 0x2, 0x0, 0x4}}, 0x2e)
ioctl$XFS_IOC_FSGROWFSLOG(r0, 0x4008586f, 0x0)

program crashed: KASAN: use-after-free Write in pppol2tp_release
validation run: crashed=true
testing program (duration=32.773232646s, {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:false Sysctl:true Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$pppl2tp-socket$inet6_udp-connect$pppl2tp-ioctl$XFS_IOC_FSGROWFSLOG
detailed listing:
executing program 0:
r0 = socket$pppl2tp(0x18, 0x1, 0x1)
r1 = socket$inet6_udp(0xa, 0x2, 0x0)
connect$pppl2tp(r0, &(0x7f0000000000)=@pppol2tpv3={0x18, 0x1, {0x3, r1, {0x2, 0x0, @multicast2}, 0x2, 0x0, 0x4}}, 0x2e)
ioctl$XFS_IOC_FSGROWFSLOG(r0, 0x4008586f, 0x0)

program crashed: KASAN: use-after-free Write in pppol2tp_release
validation run: crashed=true
reproducing took 17m25.824388414s
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_long_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1667 [inline]
BUG: KASAN: use-after-free in __mutex_trylock_fast kernel/locking/mutex.c:169 [inline]
BUG: KASAN: use-after-free in mutex_lock+0x8e/0x1c0 kernel/locking/mutex.c:288
Write of size 8 at addr ffff888110ac7150 by task syz.2.17/371

CPU: 1 PID: 371 Comm: syz.2.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:88
 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106
 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:427 [inline]
 kasan_report+0x10f/0x150 mm/kasan/report.c:444
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x249/0x2a0 mm/kasan/generic.c:189
 __kasan_check_write+0x14/0x20 mm/kasan/shadow.c:37
 instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
 atomic_long_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1667 [inline]
 __mutex_trylock_fast kernel/locking/mutex.c:169 [inline]
 mutex_lock+0x8e/0x1c0 kernel/locking/mutex.c:288
 pppol2tp_release+0x178/0x2b0 net/l2tp/l2tp_ppp.c:442
 __sock_release net/socket.c:649 [inline]
 sock_close+0xb8/0x200 net/socket.c:1335
 __fput+0x22b/0x900 fs/file_table.c:311
 ____fput+0x15/0x20 fs/file_table.c:339
 task_work_run+0x127/0x190 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0xd0/0xe0 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f3911c3ee59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd145de168 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007ffd145de250 RCX: 00007f3911c3ee59
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 0000000000005b5c R08: 0000000000000001 R09: 0000000000000000
R10: 0000001b32e20000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3911eb7fac R14: 00007f3911eb7fa8 R15: 00007f3911eb7fa0
 </TASK>

Allocated by task 371:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:433 [inline]
 ____kasan_kmalloc mm/kasan/common.c:512 [inline]
 __kasan_kmalloc+0xd4/0x100 mm/kasan/common.c:521
 kasan_kmalloc include/linux/kasan.h:227 [inline]
 __kmalloc+0x13d/0x2c0 mm/slub.c:4436
 kmalloc include/linux/slab.h:624 [inline]
 kzalloc include/linux/slab.h:750 [inline]
 l2tp_session_create+0x39/0xb60 net/l2tp/l2tp_core.c:1616
 pppol2tp_connect+0xbf5/0x1640 net/l2tp/l2tp_ppp.c:772
 __sys_connect_file net/socket.c:1922 [inline]
 __sys_connect+0x3cb/0x450 net/socket.c:1939
 __do_sys_connect net/socket.c:1949 [inline]
 __se_sys_connect net/socket.c:1946 [inline]
 __x64_sys_connect+0x7a/0x90 net/socket.c:1946
 x64_sys_call+0x7c/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:43
 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 371:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4a/0x70 mm/kasan/common.c:45
 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370
 ____kasan_slab_free+0x125/0x160 mm/kasan/common.c:365
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:373
 kasan_slab_free include/linux/kasan.h:193 [inline]
 slab_free_hook mm/slub.c:1728 [inline]
 slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1754
 slab_free mm/slub.c:3526 [inline]
 kfree+0xc4/0x270 mm/slub.c:4588
 l2tp_session_free net/l2tp/l2tp_core.c:168 [inline]
 l2tp_session_put+0xaf/0x1a0 net/l2tp/l2tp_core.c:193
 l2tp_session_delete+0x3a9/0x4a0 net/l2tp/l2tp_core.c:1589
 pppol2tp_release+0x169/0x2b0 net/l2tp/l2tp_ppp.c:439
 __sock_release net/socket.c:649 [inline]
 sock_close+0xb8/0x200 net/socket.c:1335
 __fput+0x22b/0x900 fs/file_table.c:311
 ____fput+0x15/0x20 fs/file_table.c:339
 task_work_run+0x127/0x190 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0xd0/0xe0 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

The buggy address belongs to the object at ffff888110ac7000
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 336 bytes inside of
 512-byte region [ffff888110ac7000, ffff888110ac7200)
The buggy address belongs to the page:
page:ffffea000442b100 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x110ac4
head:ffffea000442b100 order:2 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head|zone=1)
raw: 4000000000010200 0000000000000000 0000000100000001 ffff888100042f00
raw: 0000000000000000 0000000080100010 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 104, ts 4105564887, free_ts 0
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2607
 prep_new_page+0x1c/0x110 mm/page_alloc.c:2613
 get_page_from_freelist+0x2c3a/0x2cd0 mm/page_alloc.c:4487
 __alloc_pages+0x1a2/0x460 mm/page_alloc.c:5824
 alloc_slab_page mm/slub.c:-1 [inline]
 allocate_slab mm/slub.c:1937 [inline]
 new_slab+0xa0/0x4d0 mm/slub.c:2000
 ___slab_alloc+0x3ac/0x840 mm/slub.c:3033
 __slab_alloc+0x49/0x90 mm/slub.c:3120
 slab_alloc_node mm/slub.c:3211 [inline]
 slab_alloc mm/slub.c:3255 [inline]
 __kmalloc_track_caller+0x169/0x2c0 mm/slub.c:4954
 kmalloc_reserve net/core/skbuff.c:357 [inline]
 __alloc_skb+0x210/0x730 net/core/skbuff.c:428
 alloc_skb include/linux/skbuff.h:1183 [inline]
 alloc_skb_with_frags+0xa8/0x620 net/core/skbuff.c:6207
 sock_alloc_send_pskb+0x87f/0x9a0 net/core/sock.c:2542
 unix_dgram_sendmsg+0x6f3/0x19b0 net/unix/af_unix.c:1816
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 sock_write_iter+0x2a6/0x3a0 net/socket.c:1079
 call_write_iter include/linux/fs.h:2212 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0x831/0xfd0 fs/read_write.c:594
 ksys_write+0x14a/0x260 fs/read_write.c:647
 __do_sys_write fs/read_write.c:659 [inline]
 __se_sys_write fs/read_write.c:656 [inline]
 __x64_sys_write+0x7b/0x90 fs/read_write.c:656
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888110ac7000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888110ac7080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888110ac7100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                 ^
 ffff888110ac7180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888110ac7200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

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_long_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1667 [inline]
BUG: KASAN: use-after-free in __mutex_trylock_fast kernel/locking/mutex.c:169 [inline]
BUG: KASAN: use-after-free in mutex_lock+0x8e/0x1c0 kernel/locking/mutex.c:288
Write of size 8 at addr ffff888110ac7150 by task syz.2.17/371

CPU: 1 PID: 371 Comm: syz.2.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:88
 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106
 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:427 [inline]
 kasan_report+0x10f/0x150 mm/kasan/report.c:444
 check_region_inline mm/kasan/generic.c:-1 [inline]
 kasan_check_range+0x249/0x2a0 mm/kasan/generic.c:189
 __kasan_check_write+0x14/0x20 mm/kasan/shadow.c:37
 instrument_atomic_read_write include/linux/instrumented.h:101 [inline]
 atomic_long_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1667 [inline]
 __mutex_trylock_fast kernel/locking/mutex.c:169 [inline]
 mutex_lock+0x8e/0x1c0 kernel/locking/mutex.c:288
 pppol2tp_release+0x178/0x2b0 net/l2tp/l2tp_ppp.c:442
 __sock_release net/socket.c:649 [inline]
 sock_close+0xb8/0x200 net/socket.c:1335
 __fput+0x22b/0x900 fs/file_table.c:311
 ____fput+0x15/0x20 fs/file_table.c:339
 task_work_run+0x127/0x190 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0xd0/0xe0 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f3911c3ee59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd145de168 EFLAGS: 00000246 ORIG_RAX: 00000000000001b4
RAX: 0000000000000000 RBX: 00007ffd145de250 RCX: 00007f3911c3ee59
RDX: 0000000000000000 RSI: 000000000000001e RDI: 0000000000000003
RBP: 0000000000005b5c R08: 0000000000000001 R09: 0000000000000000
R10: 0000001b32e20000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f3911eb7fac R14: 00007f3911eb7fa8 R15: 00007f3911eb7fa0
 </TASK>

Allocated by task 371:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:433 [inline]
 ____kasan_kmalloc mm/kasan/common.c:512 [inline]
 __kasan_kmalloc+0xd4/0x100 mm/kasan/common.c:521
 kasan_kmalloc include/linux/kasan.h:227 [inline]
 __kmalloc+0x13d/0x2c0 mm/slub.c:4436
 kmalloc include/linux/slab.h:624 [inline]
 kzalloc include/linux/slab.h:750 [inline]
 l2tp_session_create+0x39/0xb60 net/l2tp/l2tp_core.c:1616
 pppol2tp_connect+0xbf5/0x1640 net/l2tp/l2tp_ppp.c:772
 __sys_connect_file net/socket.c:1922 [inline]
 __sys_connect+0x3cb/0x450 net/socket.c:1939
 __do_sys_connect net/socket.c:1949 [inline]
 __se_sys_connect net/socket.c:1946 [inline]
 __x64_sys_connect+0x7a/0x90 net/socket.c:1946
 x64_sys_call+0x7c/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:43
 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 371:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4a/0x70 mm/kasan/common.c:45
 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370
 ____kasan_slab_free+0x125/0x160 mm/kasan/common.c:365
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:373
 kasan_slab_free include/linux/kasan.h:193 [inline]
 slab_free_hook mm/slub.c:1728 [inline]
 slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1754
 slab_free mm/slub.c:3526 [inline]
 kfree+0xc4/0x270 mm/slub.c:4588
 l2tp_session_free net/l2tp/l2tp_core.c:168 [inline]
 l2tp_session_put+0xaf/0x1a0 net/l2tp/l2tp_core.c:193
 l2tp_session_delete+0x3a9/0x4a0 net/l2tp/l2tp_core.c:1589
 pppol2tp_release+0x169/0x2b0 net/l2tp/l2tp_ppp.c:439
 __sock_release net/socket.c:649 [inline]
 sock_close+0xb8/0x200 net/socket.c:1335
 __fput+0x22b/0x900 fs/file_table.c:311
 ____fput+0x15/0x20 fs/file_table.c:339
 task_work_run+0x127/0x190 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0xd0/0xe0 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

The buggy address belongs to the object at ffff888110ac7000
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 336 bytes inside of
 512-byte region [ffff888110ac7000, ffff888110ac7200)
The buggy address belongs to the page:
page:ffffea000442b100 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x110ac4
head:ffffea000442b100 order:2 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head|zone=1)
raw: 4000000000010200 0000000000000000 0000000100000001 ffff888100042f00
raw: 0000000000000000 0000000080100010 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 104, ts 4105564887, free_ts 0
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2607
 prep_new_page+0x1c/0x110 mm/page_alloc.c:2613
 get_page_from_freelist+0x2c3a/0x2cd0 mm/page_alloc.c:4487
 __alloc_pages+0x1a2/0x460 mm/page_alloc.c:5824
 alloc_slab_page mm/slub.c:-1 [inline]
 allocate_slab mm/slub.c:1937 [inline]
 new_slab+0xa0/0x4d0 mm/slub.c:2000
 ___slab_alloc+0x3ac/0x840 mm/slub.c:3033
 __slab_alloc+0x49/0x90 mm/slub.c:3120
 slab_alloc_node mm/slub.c:3211 [inline]
 slab_alloc mm/slub.c:3255 [inline]
 __kmalloc_track_caller+0x169/0x2c0 mm/slub.c:4954
 kmalloc_reserve net/core/skbuff.c:357 [inline]
 __alloc_skb+0x210/0x730 net/core/skbuff.c:428
 alloc_skb include/linux/skbuff.h:1183 [inline]
 alloc_skb_with_frags+0xa8/0x620 net/core/skbuff.c:6207
 sock_alloc_send_pskb+0x87f/0x9a0 net/core/sock.c:2542
 unix_dgram_sendmsg+0x6f3/0x19b0 net/unix/af_unix.c:1816
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 sock_write_iter+0x2a6/0x3a0 net/socket.c:1079
 call_write_iter include/linux/fs.h:2212 [inline]
 new_sync_write fs/read_write.c:507 [inline]
 vfs_write+0x831/0xfd0 fs/read_write.c:594
 ksys_write+0x14a/0x260 fs/read_write.c:647
 __do_sys_write fs/read_write.c:659 [inline]
 __se_sys_write fs/read_write.c:656 [inline]
 __x64_sys_write+0x7b/0x90 fs/read_write.c:656
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888110ac7000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888110ac7080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888110ac7100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                 ^
 ffff888110ac7180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888110ac7200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================