Extracting prog: 1m29.951007697s
Minimizing prog: 16m31.355230888s
Simplifying prog options: 4m20.600477738s
Extracting C: 1m16.523247149s
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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-openat$cgroup_ro-ioctl$LOOP_CONFIGURE-ioctl$LOOP_GET_STATUS64-creat-creat-mkdir-socket$inet6_icmp-socketpair$unix-syz_open_procfs-socket$tipc-openat$cgroup_ro-pipe2
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f00000005c0), 0xffff, 0x109041)
r1 = openat$cgroup_ro(0xffffffffffffff9c, &(0x7f0000000080)='memory.events.local\x00', 0x275a, 0x0)
ioctl$LOOP_CONFIGURE(r0, 0x4c0a, &(0x7f00000002c0)={r1, 0x1000, {0x2a00, 0x80010000, 0x0, 0x55, 0xfffffffffffffffe, 0x0, 0x1, 0x10, 0x15, "fee8a2ab78fc179fd1f8a0e91ddaaca7bd64c6a4b4e00d9683dda1af1ea89de2b7fb0a0100000000000000000300", "2809e8dbe108598948224ad54afac11d09000000000000008dd4992861ac1000", "90be6c09306003d8006000", [0x0, 0x750]}})
ioctl$LOOP_GET_STATUS64(r0, 0x4c05, &(0x7f00000000c0))
creat(0x0, 0x0)
creat(0x0, 0x0)
mkdir(0x0, 0x45)
socket$inet6_icmp(0xa, 0x2, 0x3a)
socketpair$unix(0x1, 0x2, 0x0, 0x0)
syz_open_procfs(0xffffffffffffffff, 0x0)
socket$tipc(0x1e, 0x2, 0x0)
openat$cgroup_ro(0xffffffffffffff9c, 0x0, 0x275a, 0x0)
pipe2(0x0, 0x0)

program crashed: KASAN: use-after-free Read in lo_open
single: successfully extracted reproducer
found reproducer with 13 syscalls
minimizing guilty program
testing program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-openat$cgroup_ro-ioctl$LOOP_CONFIGURE-ioctl$LOOP_GET_STATUS64-creat-creat-mkdir-socket$inet6_icmp-socketpair$unix-syz_open_procfs-socket$tipc-openat$cgroup_ro
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f00000005c0), 0xffff, 0x109041)
r1 = openat$cgroup_ro(0xffffffffffffff9c, &(0x7f0000000080)='memory.events.local\x00', 0x275a, 0x0)
ioctl$LOOP_CONFIGURE(r0, 0x4c0a, &(0x7f00000002c0)={r1, 0x1000, {0x2a00, 0x80010000, 0x0, 0x55, 0xfffffffffffffffe, 0x0, 0x1, 0x10, 0x15, "fee8a2ab78fc179fd1f8a0e91ddaaca7bd64c6a4b4e00d9683dda1af1ea89de2b7fb0a0100000000000000000300", "2809e8dbe108598948224ad54afac11d09000000000000008dd4992861ac1000", "90be6c09306003d8006000", [0x0, 0x750]}})
ioctl$LOOP_GET_STATUS64(r0, 0x4c05, &(0x7f00000000c0))
creat(0x0, 0x0)
creat(0x0, 0x0)
mkdir(0x0, 0x45)
socket$inet6_icmp(0xa, 0x2, 0x3a)
socketpair$unix(0x1, 0x2, 0x0, 0x0)
syz_open_procfs(0xffffffffffffffff, 0x0)
socket$tipc(0x1e, 0x2, 0x0)
openat$cgroup_ro(0xffffffffffffff9c, 0x0, 0x275a, 0x0)

program crashed: KASAN: use-after-free Read in lo_open
testing program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-openat$cgroup_ro-ioctl$LOOP_CONFIGURE-ioctl$LOOP_GET_STATUS64-creat-creat-mkdir-socket$inet6_icmp-socketpair$unix-syz_open_procfs-socket$tipc
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f00000005c0), 0xffff, 0x109041)
r1 = openat$cgroup_ro(0xffffffffffffff9c, &(0x7f0000000080)='memory.events.local\x00', 0x275a, 0x0)
ioctl$LOOP_CONFIGURE(r0, 0x4c0a, &(0x7f00000002c0)={r1, 0x1000, {0x2a00, 0x80010000, 0x0, 0x55, 0xfffffffffffffffe, 0x0, 0x1, 0x10, 0x15, "fee8a2ab78fc179fd1f8a0e91ddaaca7bd64c6a4b4e00d9683dda1af1ea89de2b7fb0a0100000000000000000300", "2809e8dbe108598948224ad54afac11d09000000000000008dd4992861ac1000", "90be6c09306003d8006000", [0x0, 0x750]}})
ioctl$LOOP_GET_STATUS64(r0, 0x4c05, &(0x7f00000000c0))
creat(0x0, 0x0)
creat(0x0, 0x0)
mkdir(0x0, 0x45)
socket$inet6_icmp(0xa, 0x2, 0x3a)
socketpair$unix(0x1, 0x2, 0x0, 0x0)
syz_open_procfs(0xffffffffffffffff, 0x0)
socket$tipc(0x1e, 0x2, 0x0)

program crashed: KASAN: use-after-free Read in lo_open
testing program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-openat$cgroup_ro-ioctl$LOOP_CONFIGURE-ioctl$LOOP_GET_STATUS64-creat-creat-mkdir-socket$inet6_icmp-socketpair$unix-syz_open_procfs
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f00000005c0), 0xffff, 0x109041)
r1 = openat$cgroup_ro(0xffffffffffffff9c, &(0x7f0000000080)='memory.events.local\x00', 0x275a, 0x0)
ioctl$LOOP_CONFIGURE(r0, 0x4c0a, &(0x7f00000002c0)={r1, 0x1000, {0x2a00, 0x80010000, 0x0, 0x55, 0xfffffffffffffffe, 0x0, 0x1, 0x10, 0x15, "fee8a2ab78fc179fd1f8a0e91ddaaca7bd64c6a4b4e00d9683dda1af1ea89de2b7fb0a0100000000000000000300", "2809e8dbe108598948224ad54afac11d09000000000000008dd4992861ac1000", "90be6c09306003d8006000", [0x0, 0x750]}})
ioctl$LOOP_GET_STATUS64(r0, 0x4c05, &(0x7f00000000c0))
creat(0x0, 0x0)
creat(0x0, 0x0)
mkdir(0x0, 0x45)
socket$inet6_icmp(0xa, 0x2, 0x3a)
socketpair$unix(0x1, 0x2, 0x0, 0x0)
syz_open_procfs(0xffffffffffffffff, 0x0)

program crashed: KASAN: use-after-free Read in lo_open
testing program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-openat$cgroup_ro-ioctl$LOOP_CONFIGURE-ioctl$LOOP_GET_STATUS64-creat-creat-mkdir-socket$inet6_icmp-socketpair$unix
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f00000005c0), 0xffff, 0x109041)
r1 = openat$cgroup_ro(0xffffffffffffff9c, &(0x7f0000000080)='memory.events.local\x00', 0x275a, 0x0)
ioctl$LOOP_CONFIGURE(r0, 0x4c0a, &(0x7f00000002c0)={r1, 0x1000, {0x2a00, 0x80010000, 0x0, 0x55, 0xfffffffffffffffe, 0x0, 0x1, 0x10, 0x15, "fee8a2ab78fc179fd1f8a0e91ddaaca7bd64c6a4b4e00d9683dda1af1ea89de2b7fb0a0100000000000000000300", "2809e8dbe108598948224ad54afac11d09000000000000008dd4992861ac1000", "90be6c09306003d8006000", [0x0, 0x750]}})
ioctl$LOOP_GET_STATUS64(r0, 0x4c05, &(0x7f00000000c0))
creat(0x0, 0x0)
creat(0x0, 0x0)
mkdir(0x0, 0x45)
socket$inet6_icmp(0xa, 0x2, 0x3a)
socketpair$unix(0x1, 0x2, 0x0, 0x0)

program crashed: KASAN: use-after-free Read in lo_open
testing program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-openat$cgroup_ro-ioctl$LOOP_CONFIGURE-ioctl$LOOP_GET_STATUS64-creat-creat-mkdir-socket$inet6_icmp
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f00000005c0), 0xffff, 0x109041)
r1 = openat$cgroup_ro(0xffffffffffffff9c, &(0x7f0000000080)='memory.events.local\x00', 0x275a, 0x0)
ioctl$LOOP_CONFIGURE(r0, 0x4c0a, &(0x7f00000002c0)={r1, 0x1000, {0x2a00, 0x80010000, 0x0, 0x55, 0xfffffffffffffffe, 0x0, 0x1, 0x10, 0x15, "fee8a2ab78fc179fd1f8a0e91ddaaca7bd64c6a4b4e00d9683dda1af1ea89de2b7fb0a0100000000000000000300", "2809e8dbe108598948224ad54afac11d09000000000000008dd4992861ac1000", "90be6c09306003d8006000", [0x0, 0x750]}})
ioctl$LOOP_GET_STATUS64(r0, 0x4c05, &(0x7f00000000c0))
creat(0x0, 0x0)
creat(0x0, 0x0)
mkdir(0x0, 0x45)
socket$inet6_icmp(0xa, 0x2, 0x3a)

program crashed: KASAN: use-after-free Read in lo_open
testing program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-openat$cgroup_ro-ioctl$LOOP_CONFIGURE-ioctl$LOOP_GET_STATUS64-creat-creat-mkdir
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f00000005c0), 0xffff, 0x109041)
r1 = openat$cgroup_ro(0xffffffffffffff9c, &(0x7f0000000080)='memory.events.local\x00', 0x275a, 0x0)
ioctl$LOOP_CONFIGURE(r0, 0x4c0a, &(0x7f00000002c0)={r1, 0x1000, {0x2a00, 0x80010000, 0x0, 0x55, 0xfffffffffffffffe, 0x0, 0x1, 0x10, 0x15, "fee8a2ab78fc179fd1f8a0e91ddaaca7bd64c6a4b4e00d9683dda1af1ea89de2b7fb0a0100000000000000000300", "2809e8dbe108598948224ad54afac11d09000000000000008dd4992861ac1000", "90be6c09306003d8006000", [0x0, 0x750]}})
ioctl$LOOP_GET_STATUS64(r0, 0x4c05, &(0x7f00000000c0))
creat(0x0, 0x0)
creat(0x0, 0x0)
mkdir(0x0, 0x45)

program crashed: KASAN: use-after-free Read in lo_open
testing program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-openat$cgroup_ro-ioctl$LOOP_CONFIGURE-ioctl$LOOP_GET_STATUS64-creat-creat
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f00000005c0), 0xffff, 0x109041)
r1 = openat$cgroup_ro(0xffffffffffffff9c, &(0x7f0000000080)='memory.events.local\x00', 0x275a, 0x0)
ioctl$LOOP_CONFIGURE(r0, 0x4c0a, &(0x7f00000002c0)={r1, 0x1000, {0x2a00, 0x80010000, 0x0, 0x55, 0xfffffffffffffffe, 0x0, 0x1, 0x10, 0x15, "fee8a2ab78fc179fd1f8a0e91ddaaca7bd64c6a4b4e00d9683dda1af1ea89de2b7fb0a0100000000000000000300", "2809e8dbe108598948224ad54afac11d09000000000000008dd4992861ac1000", "90be6c09306003d8006000", [0x0, 0x750]}})
ioctl$LOOP_GET_STATUS64(r0, 0x4c05, &(0x7f00000000c0))
creat(0x0, 0x0)
creat(0x0, 0x0)

program crashed: KASAN: use-after-free Read in lo_open
testing program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-openat$cgroup_ro-ioctl$LOOP_CONFIGURE-ioctl$LOOP_GET_STATUS64-creat
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f00000005c0), 0xffff, 0x109041)
r1 = openat$cgroup_ro(0xffffffffffffff9c, &(0x7f0000000080)='memory.events.local\x00', 0x275a, 0x0)
ioctl$LOOP_CONFIGURE(r0, 0x4c0a, &(0x7f00000002c0)={r1, 0x1000, {0x2a00, 0x80010000, 0x0, 0x55, 0xfffffffffffffffe, 0x0, 0x1, 0x10, 0x15, "fee8a2ab78fc179fd1f8a0e91ddaaca7bd64c6a4b4e00d9683dda1af1ea89de2b7fb0a0100000000000000000300", "2809e8dbe108598948224ad54afac11d09000000000000008dd4992861ac1000", "90be6c09306003d8006000", [0x0, 0x750]}})
ioctl$LOOP_GET_STATUS64(r0, 0x4c05, &(0x7f00000000c0))
creat(0x0, 0x0)

program crashed: KASAN: use-after-free Read in lo_open
testing program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-openat$cgroup_ro-ioctl$LOOP_CONFIGURE-ioctl$LOOP_GET_STATUS64
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f00000005c0), 0xffff, 0x109041)
r1 = openat$cgroup_ro(0xffffffffffffff9c, &(0x7f0000000080)='memory.events.local\x00', 0x275a, 0x0)
ioctl$LOOP_CONFIGURE(r0, 0x4c0a, &(0x7f00000002c0)={r1, 0x1000, {0x2a00, 0x80010000, 0x0, 0x55, 0xfffffffffffffffe, 0x0, 0x1, 0x10, 0x15, "fee8a2ab78fc179fd1f8a0e91ddaaca7bd64c6a4b4e00d9683dda1af1ea89de2b7fb0a0100000000000000000300", "2809e8dbe108598948224ad54afac11d09000000000000008dd4992861ac1000", "90be6c09306003d8006000", [0x0, 0x750]}})
ioctl$LOOP_GET_STATUS64(r0, 0x4c05, &(0x7f00000000c0))

program crashed: KASAN: use-after-free Read in lo_open
testing program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-openat$cgroup_ro-ioctl$LOOP_CONFIGURE
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f00000005c0), 0xffff, 0x109041)
r1 = openat$cgroup_ro(0xffffffffffffff9c, &(0x7f0000000080)='memory.events.local\x00', 0x275a, 0x0)
ioctl$LOOP_CONFIGURE(r0, 0x4c0a, &(0x7f00000002c0)={r1, 0x1000, {0x2a00, 0x80010000, 0x0, 0x55, 0xfffffffffffffffe, 0x0, 0x1, 0x10, 0x15, "fee8a2ab78fc179fd1f8a0e91ddaaca7bd64c6a4b4e00d9683dda1af1ea89de2b7fb0a0100000000000000000300", "2809e8dbe108598948224ad54afac11d09000000000000008dd4992861ac1000", "90be6c09306003d8006000", [0x0, 0x750]}})

program did not crash
testing program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-openat$cgroup_ro-ioctl$LOOP_GET_STATUS64
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f00000005c0), 0xffff, 0x109041)
openat$cgroup_ro(0xffffffffffffff9c, &(0x7f0000000080)='memory.events.local\x00', 0x275a, 0x0)
ioctl$LOOP_GET_STATUS64(r0, 0x4c05, &(0x7f00000000c0))

program did not crash
testing program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-ioctl$LOOP_CONFIGURE-ioctl$LOOP_GET_STATUS64
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f00000005c0), 0xffff, 0x109041)
ioctl$LOOP_CONFIGURE(r0, 0x4c0a, &(0x7f00000002c0)={0xffffffffffffffff, 0x1000, {0x2a00, 0x80010000, 0x0, 0x55, 0xfffffffffffffffe, 0x0, 0x1, 0x10, 0x15, "fee8a2ab78fc179fd1f8a0e91ddaaca7bd64c6a4b4e00d9683dda1af1ea89de2b7fb0a0100000000000000000300", "2809e8dbe108598948224ad54afac11d09000000000000008dd4992861ac1000", "90be6c09306003d8006000", [0x0, 0x750]}})
ioctl$LOOP_GET_STATUS64(r0, 0x4c05, &(0x7f00000000c0))

program did not crash
testing program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): openat$cgroup_ro-ioctl$LOOP_CONFIGURE-ioctl$LOOP_GET_STATUS64
detailed listing:
executing program 0:
r0 = openat$cgroup_ro(0xffffffffffffff9c, &(0x7f0000000080)='memory.events.local\x00', 0x275a, 0x0)
ioctl$LOOP_CONFIGURE(0xffffffffffffffff, 0x4c0a, &(0x7f00000002c0)={r0, 0x1000, {0x2a00, 0x80010000, 0x0, 0x55, 0xfffffffffffffffe, 0x0, 0x1, 0x10, 0x15, "fee8a2ab78fc179fd1f8a0e91ddaaca7bd64c6a4b4e00d9683dda1af1ea89de2b7fb0a0100000000000000000300", "2809e8dbe108598948224ad54afac11d09000000000000008dd4992861ac1000", "90be6c09306003d8006000", [0x0, 0x750]}})
ioctl$LOOP_GET_STATUS64(0xffffffffffffffff, 0x4c05, &(0x7f00000000c0))

program did not crash
testing program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-openat$cgroup_ro-ioctl$LOOP_CONFIGURE-ioctl$LOOP_GET_STATUS64
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(0x0, 0xffff, 0x109041)
r1 = openat$cgroup_ro(0xffffffffffffff9c, &(0x7f0000000080)='memory.events.local\x00', 0x275a, 0x0)
ioctl$LOOP_CONFIGURE(r0, 0x4c0a, &(0x7f00000002c0)={r1, 0x1000, {0x2a00, 0x80010000, 0x0, 0x55, 0xfffffffffffffffe, 0x0, 0x1, 0x10, 0x15, "fee8a2ab78fc179fd1f8a0e91ddaaca7bd64c6a4b4e00d9683dda1af1ea89de2b7fb0a0100000000000000000300", "2809e8dbe108598948224ad54afac11d09000000000000008dd4992861ac1000", "90be6c09306003d8006000", [0x0, 0x750]}})
ioctl$LOOP_GET_STATUS64(r0, 0x4c05, &(0x7f00000000c0))

program did not crash
testing program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-openat$cgroup_ro-ioctl$LOOP_CONFIGURE-ioctl$LOOP_GET_STATUS64
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f00000005c0), 0xffff, 0x109041)
r1 = openat$cgroup_ro(0xffffffffffffff9c, 0x0, 0x275a, 0x0)
ioctl$LOOP_CONFIGURE(r0, 0x4c0a, &(0x7f00000002c0)={r1, 0x1000, {0x2a00, 0x80010000, 0x0, 0x55, 0xfffffffffffffffe, 0x0, 0x1, 0x10, 0x15, "fee8a2ab78fc179fd1f8a0e91ddaaca7bd64c6a4b4e00d9683dda1af1ea89de2b7fb0a0100000000000000000300", "2809e8dbe108598948224ad54afac11d09000000000000008dd4992861ac1000", "90be6c09306003d8006000", [0x0, 0x750]}})
ioctl$LOOP_GET_STATUS64(r0, 0x4c05, &(0x7f00000000c0))

program did not crash
testing program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-openat$cgroup_ro-ioctl$LOOP_CONFIGURE-ioctl$LOOP_GET_STATUS64
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f00000005c0), 0xffff, 0x109041)
openat$cgroup_ro(0xffffffffffffff9c, &(0x7f0000000080)='memory.events.local\x00', 0x275a, 0x0)
ioctl$LOOP_CONFIGURE(r0, 0x4c0a, 0x0)
ioctl$LOOP_GET_STATUS64(r0, 0x4c05, &(0x7f00000000c0))

program did not crash
testing program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-openat$cgroup_ro-ioctl$LOOP_CONFIGURE-ioctl$LOOP_GET_STATUS64
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f00000005c0), 0xffff, 0x109041)
r1 = openat$cgroup_ro(0xffffffffffffff9c, &(0x7f0000000080)='memory.events.local\x00', 0x275a, 0x0)
ioctl$LOOP_CONFIGURE(r0, 0x4c0a, &(0x7f00000002c0)={r1, 0x1000, {0x2a00, 0x80010000, 0x0, 0x55, 0xfffffffffffffffe, 0x0, 0x1, 0x10, 0x15, "fee8a2ab78fc179fd1f8a0e91ddaaca7bd64c6a4b4e00d9683dda1af1ea89de2b7fb0a0100000000000000000300", "2809e8dbe108598948224ad54afac11d09000000000000008dd4992861ac1000", "90be6c09306003d8006000", [0x0, 0x750]}})
ioctl$LOOP_GET_STATUS64(r0, 0x4c05, 0x0)

program did not crash
extracting C reproducer
testing compiled C program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-openat$cgroup_ro-ioctl$LOOP_CONFIGURE-ioctl$LOOP_GET_STATUS64
program did not crash
simplifying guilty program options
testing program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-openat$cgroup_ro-ioctl$LOOP_CONFIGURE-ioctl$LOOP_GET_STATUS64
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f00000005c0), 0xffff, 0x109041)
r1 = openat$cgroup_ro(0xffffffffffffff9c, &(0x7f0000000080)='memory.events.local\x00', 0x275a, 0x0)
ioctl$LOOP_CONFIGURE(r0, 0x4c0a, &(0x7f00000002c0)={r1, 0x1000, {0x2a00, 0x80010000, 0x0, 0x55, 0xfffffffffffffffe, 0x0, 0x1, 0x10, 0x15, "fee8a2ab78fc179fd1f8a0e91ddaaca7bd64c6a4b4e00d9683dda1af1ea89de2b7fb0a0100000000000000000300", "2809e8dbe108598948224ad54afac11d09000000000000008dd4992861ac1000", "90be6c09306003d8006000", [0x0, 0x750]}})
ioctl$LOOP_GET_STATUS64(r0, 0x4c05, &(0x7f00000000c0))

program did not crash
testing program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-openat$cgroup_ro-ioctl$LOOP_CONFIGURE-ioctl$LOOP_GET_STATUS64
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f00000005c0), 0xffff, 0x109041)
r1 = openat$cgroup_ro(0xffffffffffffff9c, &(0x7f0000000080)='memory.events.local\x00', 0x275a, 0x0)
ioctl$LOOP_CONFIGURE(r0, 0x4c0a, &(0x7f00000002c0)={r1, 0x1000, {0x2a00, 0x80010000, 0x0, 0x55, 0xfffffffffffffffe, 0x0, 0x1, 0x10, 0x15, "fee8a2ab78fc179fd1f8a0e91ddaaca7bd64c6a4b4e00d9683dda1af1ea89de2b7fb0a0100000000000000000300", "2809e8dbe108598948224ad54afac11d09000000000000008dd4992861ac1000", "90be6c09306003d8006000", [0x0, 0x750]}})
ioctl$LOOP_GET_STATUS64(r0, 0x4c05, &(0x7f00000000c0))

program did not crash
testing program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-openat$cgroup_ro-ioctl$LOOP_CONFIGURE-ioctl$LOOP_GET_STATUS64
detailed listing:
executing program 0:
r0 = syz_open_dev$loop(&(0x7f00000005c0), 0xffff, 0x109041)
r1 = openat$cgroup_ro(0xffffffffffffff9c, &(0x7f0000000080)='memory.events.local\x00', 0x275a, 0x0)
ioctl$LOOP_CONFIGURE(r0, 0x4c0a, &(0x7f00000002c0)={r1, 0x1000, {0x2a00, 0x80010000, 0x0, 0x55, 0xfffffffffffffffe, 0x0, 0x1, 0x10, 0x15, "fee8a2ab78fc179fd1f8a0e91ddaaca7bd64c6a4b4e00d9683dda1af1ea89de2b7fb0a0100000000000000000300", "2809e8dbe108598948224ad54afac11d09000000000000008dd4992861ac1000", "90be6c09306003d8006000", [0x0, 0x750]}})
ioctl$LOOP_GET_STATUS64(r0, 0x4c05, &(0x7f00000000c0))

program crashed: KASAN: use-after-free Read in lo_open
extracting C reproducer
testing compiled C program (duration=45.474864346s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_open_dev$loop-openat$cgroup_ro-ioctl$LOOP_CONFIGURE-ioctl$LOOP_GET_STATUS64
program did not crash
reproducing took 23m10.982392335s
repro crashed as (corrupted=false):
==================================================================
BUG: KASAN: use-after-free in mutex_can_spin_on_owner kernel/locking/mutex.c:617 [inline]
BUG: KASAN: use-after-free in mutex_optimistic_spin kernel/locking/mutex.c:661 [inline]
BUG: KASAN: use-after-free in __mutex_lock_common kernel/locking/mutex.c:973 [inline]
BUG: KASAN: use-after-free in __mutex_lock+0xace/0xe30 kernel/locking/mutex.c:1114
Read of size 4 at addr ffff8881e964af78 by task syz-executor/443

CPU: 0 PID: 443 Comm: syz-executor Not tainted 5.4.292-syzkaller-00021-gcd8e74fa0fa3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 __dump_stack+0x1e/0x20 lib/dump_stack.c:77
 dump_stack+0x15b/0x1b8 lib/dump_stack.c:118
 print_address_description+0x8d/0x4c0 mm/kasan/report.c:384
 __kasan_report+0xef/0x120 mm/kasan/report.c:516
 kasan_report+0x30/0x60 mm/kasan/common.c:653
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131
 mutex_can_spin_on_owner kernel/locking/mutex.c:617 [inline]
 mutex_optimistic_spin kernel/locking/mutex.c:661 [inline]
 __mutex_lock_common kernel/locking/mutex.c:973 [inline]
 __mutex_lock+0xace/0xe30 kernel/locking/mutex.c:1114
 __mutex_lock_killable_slowpath+0xe/0x10 kernel/locking/mutex.c:1381
 mutex_lock_killable+0xd3/0xe0 kernel/locking/mutex.c:1348
 lo_open+0x1d/0xc0 drivers/block/loop.c:1899
 __blkdev_get+0x610/0x1560 fs/block_dev.c:1581
 blkdev_get+0x68/0x380 fs/block_dev.c:1714
 blkdev_open+0x1cb/0x2b0 fs/block_dev.c:1856
 do_dentry_open+0x8b5/0x1030 fs/open.c:806
 vfs_open+0x73/0x80 fs/open.c:920
 do_last fs/namei.c:3565 [inline]
 path_openat+0x2a5e/0x35c0 fs/namei.c:3683
 do_filp_open+0x1ae/0x3f0 fs/namei.c:3713
 do_sys_open+0x2bb/0x5d0 fs/open.c:1123
 __do_sys_openat fs/open.c:1150 [inline]
 __se_sys_openat fs/open.c:1144 [inline]
 __x64_sys_openat+0xa2/0xb0 fs/open.c:1144
 do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7fa40d621251
Code: 75 57 89 f0 25 00 00 41 00 3d 00 00 41 00 74 49 80 3d fa 72 1f 00 00 74 6d 89 da 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 93 00 00 00 48 8b 54 24 28 64 48 2b 14 25
RSP: 002b:00007fff3ee340f0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fa40d621251
RDX: 0000000000000002 RSI: 00007fff3ee34200 RDI: 00000000ffffff9c
RBP: 00007fff3ee34200 R08: 000000000000000a R09: 00007fff3ee33eb7
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007fa40d811260 R14: 0000000000000003 R15: 00007fff3ee34200

Allocated by task 434:
 save_stack mm/kasan/common.c:70 [inline]
 set_track mm/kasan/common.c:78 [inline]
 __kasan_kmalloc+0x162/0x200 mm/kasan/common.c:529
 kasan_slab_alloc+0x12/0x20 mm/kasan/common.c:537
 slab_post_alloc_hook mm/slab.h:584 [inline]
 slab_alloc_node mm/slub.c:2829 [inline]
 slab_alloc mm/slub.c:2837 [inline]
 kmem_cache_alloc+0xe2/0x270 mm/slub.c:2842
 kmem_cache_alloc_node include/linux/slab.h:427 [inline]
 alloc_task_struct_node kernel/fork.c:171 [inline]
 dup_task_struct+0x57/0x640 kernel/fork.c:882
 copy_process+0x503/0x2cf0 kernel/fork.c:1889
 _do_fork+0x190/0x860 kernel/fork.c:2399
 __do_sys_clone3 kernel/fork.c:2688 [inline]
 __se_sys_clone3 kernel/fork.c:2675 [inline]
 __x64_sys_clone3+0x1de/0x1f0 kernel/fork.c:2675
 do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1

Freed by task 17:
 save_stack mm/kasan/common.c:70 [inline]
 set_track mm/kasan/common.c:78 [inline]
 kasan_set_free_info mm/kasan/common.c:345 [inline]
 __kasan_slab_free+0x1c3/0x280 mm/kasan/common.c:487
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:496
 slab_free_hook mm/slub.c:1455 [inline]
 slab_free_freelist_hook+0xb7/0x180 mm/slub.c:1494
 slab_free mm/slub.c:3080 [inline]
 kmem_cache_free+0x10c/0x2c0 mm/slub.c:3096
 free_task_struct kernel/fork.c:176 [inline]
 free_task+0xe9/0x150 kernel/fork.c:480
 __put_task_struct+0x2b7/0x420 kernel/fork.c:755
 put_task_struct include/linux/sched/task.h:147 [inline]
 delayed_put_task_struct+0x71/0x210 kernel/exit.c:229
 __rcu_reclaim kernel/rcu/rcu.h:222 [inline]
 rcu_do_batch+0x446/0x980 kernel/rcu/tree.c:2167
 rcu_core+0x4bd/0xbd0 kernel/rcu/tree.c:2387
 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2396
 __do_softirq+0x236/0x660 kernel/softirq.c:292

The buggy address belongs to the object at ffff8881e964af40
 which belongs to the cache task_struct of size 3904
The buggy address is located 56 bytes inside of
 3904-byte region [ffff8881e964af40, ffff8881e964be80)
The buggy address belongs to the page:
page:ffffea0007a59200 refcount:1 mapcount:0 mapping:ffff8881f5cf4f00 index:0x0 compound_mapcount: 0
flags: 0x8000000000010200(slab|head)
raw: 8000000000010200 dead000000000100 dead000000000122 ffff8881f5cf4f00
raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL)
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook mm/page_alloc.c:2165 [inline]
 prep_new_page+0x35e/0x370 mm/page_alloc.c:2171
 get_page_from_freelist+0x1296/0x1310 mm/page_alloc.c:3794
 __alloc_pages_nodemask+0x202/0x4b0 mm/page_alloc.c:4894
 alloc_slab_page+0x3c/0x3b0 mm/slub.c:343
 allocate_slab mm/slub.c:1683 [inline]
 new_slab+0x93/0x420 mm/slub.c:1749
 new_slab_objects mm/slub.c:2505 [inline]
 ___slab_alloc+0x29e/0x420 mm/slub.c:2667
 __slab_alloc+0x63/0xa0 mm/slub.c:2707
 slab_alloc_node mm/slub.c:2792 [inline]
 slab_alloc mm/slub.c:2837 [inline]
 kmem_cache_alloc+0x12c/0x270 mm/slub.c:2842
 kmem_cache_alloc_node include/linux/slab.h:427 [inline]
 alloc_task_struct_node kernel/fork.c:171 [inline]
 dup_task_struct+0x57/0x640 kernel/fork.c:882
 copy_process+0x503/0x2cf0 kernel/fork.c:1889
 _do_fork+0x190/0x860 kernel/fork.c:2399
 __do_sys_clone3 kernel/fork.c:2688 [inline]
 __se_sys_clone3 kernel/fork.c:2675 [inline]
 __x64_sys_clone3+0x1de/0x1f0 kernel/fork.c:2675
 do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1176 [inline]
 __free_pages_ok+0x7e4/0x910 mm/page_alloc.c:1438
 free_the_page mm/page_alloc.c:4956 [inline]
 __free_pages+0x8c/0x110 mm/page_alloc.c:4962
 __free_slab+0x218/0x2d0 mm/slub.c:1774
 free_slab mm/slub.c:1789 [inline]
 discard_slab+0x29/0x40 mm/slub.c:1795
 __slab_free+0x374/0x380 mm/slub.c:3012
 do_slab_free mm/slub.c:3068 [inline]
 ___cache_free+0xbb/0xd0 mm/slub.c:3087
 qlink_free+0x23/0x30 mm/kasan/quarantine.c:148
 qlist_free_all+0x5f/0xb0 mm/kasan/quarantine.c:167
 quarantine_reduce+0x1a8/0x200 mm/kasan/quarantine.c:260
 __kasan_kmalloc+0x42/0x200 mm/kasan/common.c:507
 kasan_slab_alloc+0x12/0x20 mm/kasan/common.c:537
 slab_post_alloc_hook mm/slab.h:584 [inline]
 slab_alloc_node mm/slub.c:2829 [inline]
 slab_alloc mm/slub.c:2837 [inline]
 __kmalloc+0x106/0x2f0 mm/slub.c:3909
 __kmalloc_node include/linux/slab.h:422 [inline]
 kmalloc_node include/linux/slab.h:599 [inline]
 kzalloc_node include/linux/slab.h:701 [inline]
 qdisc_alloc+0x7f/0x7e0 net/sched/sch_generic.c:864
 qdisc_create_dflt+0x69/0x270 net/sched/sch_generic.c:937
 attach_one_default_qdisc net/sched/sch_generic.c:1089 [inline]
 netdev_for_each_tx_queue include/linux/netdevice.h:2194 [inline]
 attach_default_qdiscs net/sched/sch_generic.c:1108 [inline]
 dev_activate+0x2ec/0xc80 net/sched/sch_generic.c:1154
 __dev_open+0x2d3/0x3f0 net/core/dev.c:1335

Memory state around the buggy address:
 ffff8881e964ae00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881e964ae80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
>ffff8881e964af00: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
                                                                ^
 ffff8881e964af80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881e964b000: 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 mutex_can_spin_on_owner kernel/locking/mutex.c:617 [inline]
BUG: KASAN: use-after-free in mutex_optimistic_spin kernel/locking/mutex.c:661 [inline]
BUG: KASAN: use-after-free in __mutex_lock_common kernel/locking/mutex.c:973 [inline]
BUG: KASAN: use-after-free in __mutex_lock+0xace/0xe30 kernel/locking/mutex.c:1114
Read of size 4 at addr ffff8881e964af78 by task syz-executor/443

CPU: 0 PID: 443 Comm: syz-executor Not tainted 5.4.292-syzkaller-00021-gcd8e74fa0fa3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 __dump_stack+0x1e/0x20 lib/dump_stack.c:77
 dump_stack+0x15b/0x1b8 lib/dump_stack.c:118
 print_address_description+0x8d/0x4c0 mm/kasan/report.c:384
 __kasan_report+0xef/0x120 mm/kasan/report.c:516
 kasan_report+0x30/0x60 mm/kasan/common.c:653
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/generic_report.c:131
 mutex_can_spin_on_owner kernel/locking/mutex.c:617 [inline]
 mutex_optimistic_spin kernel/locking/mutex.c:661 [inline]
 __mutex_lock_common kernel/locking/mutex.c:973 [inline]
 __mutex_lock+0xace/0xe30 kernel/locking/mutex.c:1114
 __mutex_lock_killable_slowpath+0xe/0x10 kernel/locking/mutex.c:1381
 mutex_lock_killable+0xd3/0xe0 kernel/locking/mutex.c:1348
 lo_open+0x1d/0xc0 drivers/block/loop.c:1899
 __blkdev_get+0x610/0x1560 fs/block_dev.c:1581
 blkdev_get+0x68/0x380 fs/block_dev.c:1714
 blkdev_open+0x1cb/0x2b0 fs/block_dev.c:1856
 do_dentry_open+0x8b5/0x1030 fs/open.c:806
 vfs_open+0x73/0x80 fs/open.c:920
 do_last fs/namei.c:3565 [inline]
 path_openat+0x2a5e/0x35c0 fs/namei.c:3683
 do_filp_open+0x1ae/0x3f0 fs/namei.c:3713
 do_sys_open+0x2bb/0x5d0 fs/open.c:1123
 __do_sys_openat fs/open.c:1150 [inline]
 __se_sys_openat fs/open.c:1144 [inline]
 __x64_sys_openat+0xa2/0xb0 fs/open.c:1144
 do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1
RIP: 0033:0x7fa40d621251
Code: 75 57 89 f0 25 00 00 41 00 3d 00 00 41 00 74 49 80 3d fa 72 1f 00 00 74 6d 89 da 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 0f 87 93 00 00 00 48 8b 54 24 28 64 48 2b 14 25
RSP: 002b:00007fff3ee340f0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007fa40d621251
RDX: 0000000000000002 RSI: 00007fff3ee34200 RDI: 00000000ffffff9c
RBP: 00007fff3ee34200 R08: 000000000000000a R09: 00007fff3ee33eb7
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007fa40d811260 R14: 0000000000000003 R15: 00007fff3ee34200

Allocated by task 434:
 save_stack mm/kasan/common.c:70 [inline]
 set_track mm/kasan/common.c:78 [inline]
 __kasan_kmalloc+0x162/0x200 mm/kasan/common.c:529
 kasan_slab_alloc+0x12/0x20 mm/kasan/common.c:537
 slab_post_alloc_hook mm/slab.h:584 [inline]
 slab_alloc_node mm/slub.c:2829 [inline]
 slab_alloc mm/slub.c:2837 [inline]
 kmem_cache_alloc+0xe2/0x270 mm/slub.c:2842
 kmem_cache_alloc_node include/linux/slab.h:427 [inline]
 alloc_task_struct_node kernel/fork.c:171 [inline]
 dup_task_struct+0x57/0x640 kernel/fork.c:882
 copy_process+0x503/0x2cf0 kernel/fork.c:1889
 _do_fork+0x190/0x860 kernel/fork.c:2399
 __do_sys_clone3 kernel/fork.c:2688 [inline]
 __se_sys_clone3 kernel/fork.c:2675 [inline]
 __x64_sys_clone3+0x1de/0x1f0 kernel/fork.c:2675
 do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1

Freed by task 17:
 save_stack mm/kasan/common.c:70 [inline]
 set_track mm/kasan/common.c:78 [inline]
 kasan_set_free_info mm/kasan/common.c:345 [inline]
 __kasan_slab_free+0x1c3/0x280 mm/kasan/common.c:487
 kasan_slab_free+0xe/0x10 mm/kasan/common.c:496
 slab_free_hook mm/slub.c:1455 [inline]
 slab_free_freelist_hook+0xb7/0x180 mm/slub.c:1494
 slab_free mm/slub.c:3080 [inline]
 kmem_cache_free+0x10c/0x2c0 mm/slub.c:3096
 free_task_struct kernel/fork.c:176 [inline]
 free_task+0xe9/0x150 kernel/fork.c:480
 __put_task_struct+0x2b7/0x420 kernel/fork.c:755
 put_task_struct include/linux/sched/task.h:147 [inline]
 delayed_put_task_struct+0x71/0x210 kernel/exit.c:229
 __rcu_reclaim kernel/rcu/rcu.h:222 [inline]
 rcu_do_batch+0x446/0x980 kernel/rcu/tree.c:2167
 rcu_core+0x4bd/0xbd0 kernel/rcu/tree.c:2387
 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2396
 __do_softirq+0x236/0x660 kernel/softirq.c:292

The buggy address belongs to the object at ffff8881e964af40
 which belongs to the cache task_struct of size 3904
The buggy address is located 56 bytes inside of
 3904-byte region [ffff8881e964af40, ffff8881e964be80)
The buggy address belongs to the page:
page:ffffea0007a59200 refcount:1 mapcount:0 mapping:ffff8881f5cf4f00 index:0x0 compound_mapcount: 0
flags: 0x8000000000010200(slab|head)
raw: 8000000000010200 dead000000000100 dead000000000122 ffff8881f5cf4f00
raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL)
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook mm/page_alloc.c:2165 [inline]
 prep_new_page+0x35e/0x370 mm/page_alloc.c:2171
 get_page_from_freelist+0x1296/0x1310 mm/page_alloc.c:3794
 __alloc_pages_nodemask+0x202/0x4b0 mm/page_alloc.c:4894
 alloc_slab_page+0x3c/0x3b0 mm/slub.c:343
 allocate_slab mm/slub.c:1683 [inline]
 new_slab+0x93/0x420 mm/slub.c:1749
 new_slab_objects mm/slub.c:2505 [inline]
 ___slab_alloc+0x29e/0x420 mm/slub.c:2667
 __slab_alloc+0x63/0xa0 mm/slub.c:2707
 slab_alloc_node mm/slub.c:2792 [inline]
 slab_alloc mm/slub.c:2837 [inline]
 kmem_cache_alloc+0x12c/0x270 mm/slub.c:2842
 kmem_cache_alloc_node include/linux/slab.h:427 [inline]
 alloc_task_struct_node kernel/fork.c:171 [inline]
 dup_task_struct+0x57/0x640 kernel/fork.c:882
 copy_process+0x503/0x2cf0 kernel/fork.c:1889
 _do_fork+0x190/0x860 kernel/fork.c:2399
 __do_sys_clone3 kernel/fork.c:2688 [inline]
 __se_sys_clone3 kernel/fork.c:2675 [inline]
 __x64_sys_clone3+0x1de/0x1f0 kernel/fork.c:2675
 do_syscall_64+0xcf/0x170 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x5c/0xc1
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1176 [inline]
 __free_pages_ok+0x7e4/0x910 mm/page_alloc.c:1438
 free_the_page mm/page_alloc.c:4956 [inline]
 __free_pages+0x8c/0x110 mm/page_alloc.c:4962
 __free_slab+0x218/0x2d0 mm/slub.c:1774
 free_slab mm/slub.c:1789 [inline]
 discard_slab+0x29/0x40 mm/slub.c:1795
 __slab_free+0x374/0x380 mm/slub.c:3012
 do_slab_free mm/slub.c:3068 [inline]
 ___cache_free+0xbb/0xd0 mm/slub.c:3087
 qlink_free+0x23/0x30 mm/kasan/quarantine.c:148
 qlist_free_all+0x5f/0xb0 mm/kasan/quarantine.c:167
 quarantine_reduce+0x1a8/0x200 mm/kasan/quarantine.c:260
 __kasan_kmalloc+0x42/0x200 mm/kasan/common.c:507
 kasan_slab_alloc+0x12/0x20 mm/kasan/common.c:537
 slab_post_alloc_hook mm/slab.h:584 [inline]
 slab_alloc_node mm/slub.c:2829 [inline]
 slab_alloc mm/slub.c:2837 [inline]
 __kmalloc+0x106/0x2f0 mm/slub.c:3909
 __kmalloc_node include/linux/slab.h:422 [inline]
 kmalloc_node include/linux/slab.h:599 [inline]
 kzalloc_node include/linux/slab.h:701 [inline]
 qdisc_alloc+0x7f/0x7e0 net/sched/sch_generic.c:864
 qdisc_create_dflt+0x69/0x270 net/sched/sch_generic.c:937
 attach_one_default_qdisc net/sched/sch_generic.c:1089 [inline]
 netdev_for_each_tx_queue include/linux/netdevice.h:2194 [inline]
 attach_default_qdiscs net/sched/sch_generic.c:1108 [inline]
 dev_activate+0x2ec/0xc80 net/sched/sch_generic.c:1154
 __dev_open+0x2d3/0x3f0 net/core/dev.c:1335

Memory state around the buggy address:
 ffff8881e964ae00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881e964ae80: 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc
>ffff8881e964af00: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb
                                                                ^
 ffff8881e964af80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881e964b000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================