Extracting prog: 2m3.235387249s
Minimizing prog: 9m14.867066354s
Simplifying prog options: 0s
Extracting C: 21.444787812s
Simplifying C: 4m48.095826411s


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:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000240)='./debug\x00', 0xaf)
mount(0x0, &(0x7f0000000200)='./debug\x00', &(0x7f0000000300)='debugfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f0000000400)='./debug/split_huge_pages\x00', 0x1, 0x0)
write(r0, &(0x7f0000000600)='/#0r7', 0x5)

program crashed: general protection fault in vsscanf
program crashed: general protection fault in vsscanf
single: successfully extracted reproducer
found reproducer with 4 syscalls
minimizing guilty program
testing program (duration=33.533108512s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000240)='./debug\x00', 0xaf)
mount(0x0, &(0x7f0000000200)='./debug\x00', &(0x7f0000000300)='debugfs\x00', 0x0, 0x0)
openat(0xffffffffffffff9c, &(0x7f0000000400)='./debug/split_huge_pages\x00', 0x1, 0x0)

program did not crash
testing program (duration=33.533108512s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000240)='./debug\x00', 0xaf)
mount(0x0, &(0x7f0000000200)='./debug\x00', &(0x7f0000000300)='debugfs\x00', 0x0, 0x0)
write(0xffffffffffffffff, &(0x7f0000000600)='/#0r7', 0x5)

program did not crash
testing program (duration=33.533108512s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-openat-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000240)='./debug\x00', 0xaf)
r0 = openat(0xffffffffffffff9c, &(0x7f0000000400)='./debug/split_huge_pages\x00', 0x1, 0x0)
write(r0, &(0x7f0000000600)='/#0r7', 0x5)

program did not crash
testing program (duration=33.533108512s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection: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}}): mount-openat-write
detailed listing:
executing program 0:
mount(0x0, &(0x7f0000000200)='./debug\x00', &(0x7f0000000300)='debugfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f0000000400)='./debug/split_huge_pages\x00', 0x1, 0x0)
write(r0, &(0x7f0000000600)='/#0r7', 0x5)

program did not crash
testing program (duration=33.533108512s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, 0x0, 0xaf)
mount(0x0, &(0x7f0000000200)='./debug\x00', &(0x7f0000000300)='debugfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f0000000400)='./debug/split_huge_pages\x00', 0x1, 0x0)
write(r0, &(0x7f0000000600)='/#0r7', 0x5)

program did not crash
testing program (duration=33.533108512s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000240)='./debug\x00', 0xaf)
mount(0x0, 0x0, &(0x7f0000000300)='debugfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f0000000400)='./debug/split_huge_pages\x00', 0x1, 0x0)
write(r0, &(0x7f0000000600)='/#0r7', 0x5)

program did not crash
testing program (duration=33.533108512s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000240)='./debug\x00', 0xaf)
mount(0x0, &(0x7f0000000200)='./debug\x00', 0x0, 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f0000000400)='./debug/split_huge_pages\x00', 0x1, 0x0)
write(r0, &(0x7f0000000600)='/#0r7', 0x5)

program did not crash
testing program (duration=33.533108512s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000240)='./debug\x00', 0xaf)
mount(0x0, &(0x7f0000000200)='./debug\x00', &(0x7f0000000300)='debugfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, 0x0, 0x1, 0x0)
write(r0, &(0x7f0000000600)='/#0r7', 0x5)

program did not crash
testing program (duration=33.533108512s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000240)='./debug\x00', 0xaf)
mount(0x0, &(0x7f0000000200)='./debug\x00', &(0x7f0000000300)='debugfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f0000000400)='./debug/split_huge_pages\x00', 0x1, 0x0)
write(r0, 0x0, 0x0)

program did not crash
testing program (duration=33.533108512s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000240)='./debug\x00', 0xaf)
mount(0x0, &(0x7f0000000200)='./debug\x00', &(0x7f0000000300)='debugfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f0000000400)='./debug/split_huge_pages\x00', 0x1, 0x0)
write(r0, &(0x7f0000000600), 0x0)

program did not crash
extracting C reproducer
testing compiled C program (duration=33.533108512s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
program crashed: general protection fault in vsscanf
simplifying C reproducer
testing compiled C program (duration=33.533108512s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdirat-mount-openat-write
program crashed: general protection fault in vsscanf
testing compiled C program (duration=33.533108512s, {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}}): mkdirat-mount-openat-write
program crashed: general protection fault in vsscanf
testing compiled C program (duration=33.533108512s, {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}}): mkdirat-mount-openat-write
program crashed: general protection fault in vsscanf
testing compiled C program (duration=33.533108512s, {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}}): mkdirat-mount-openat-write
program crashed: general protection fault in vsscanf
testing compiled C program (duration=33.533108512s, {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}}): mkdirat-mount-openat-write
program crashed: general protection fault in vsscanf
testing compiled C program (duration=33.533108512s, {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}}): mkdirat-mount-openat-write
program crashed: general protection fault in vsscanf
testing program (duration=33.533108512s, {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}}): mkdirat-mount-openat-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000240)='./debug\x00', 0xaf)
mount(0x0, &(0x7f0000000200)='./debug\x00', &(0x7f0000000300)='debugfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f0000000400)='./debug/split_huge_pages\x00', 0x1, 0x0)
write(r0, &(0x7f0000000600)='/#0r7', 0x5)

program crashed: general protection fault in vsscanf
validation run: crashed=true
testing program (duration=33.533108512s, {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}}): mkdirat-mount-openat-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000240)='./debug\x00', 0xaf)
mount(0x0, &(0x7f0000000200)='./debug\x00', &(0x7f0000000300)='debugfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f0000000400)='./debug/split_huge_pages\x00', 0x1, 0x0)
write(r0, &(0x7f0000000600)='/#0r7', 0x5)

program crashed: general protection fault in vsscanf
validation run: crashed=true
testing program (duration=33.533108512s, {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}}): mkdirat-mount-openat-write
detailed listing:
executing program 0:
mkdirat(0xffffffffffffff9c, &(0x7f0000000240)='./debug\x00', 0xaf)
mount(0x0, &(0x7f0000000200)='./debug\x00', &(0x7f0000000300)='debugfs\x00', 0x0, 0x0)
r0 = openat(0xffffffffffffff9c, &(0x7f0000000400)='./debug/split_huge_pages\x00', 0x1, 0x0)
write(r0, &(0x7f0000000600)='/#0r7', 0x5)

program crashed: general protection fault in vsscanf
validation run: crashed=true
reproducing took 19m47.205298799s
repro crashed as (corrupted=false):
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 UID: 0 PID: 383 Comm: syz.2.17 Not tainted syzkaller #0 4c7c6fabea823c7a50d4a31162f440126d0e7a76
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:vsscanf+0x18c/0x24b0 lib/vsprintf.c:3444
Code: 48 c7 c6 30 c0 e3 87 e8 a2 b8 e5 fb 41 83 fe 25 74 4d 45 85 f6 0f 84 a4 21 00 00 48 ff c3 48 89 5c 24 58 4c 89 f8 48 c1 e8 03 <42> 0f b6 04 28 84 c0 0f 85 8e 1b 00 00 41 0f b6 1f 45 0f b6 f6 44
RSP: 0018:ffffc90001aaf5a0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffffff86364c61 RCX: 0000000000000001
RDX: ffffffff85a1c41e RSI: ffffffff87e3c030 RDI: 0000000000000030
RBP: ffffc90001aaf6b0 R08: ffff888128c1a600 R09: 0000000000000002
R10: 0000000000000025 R11: 0000000000000000 R12: ffffffff86364c60
R13: dffffc0000000000 R14: 0000000000000030 R15: 0000000000000000
FS:  00005555740ad500(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f05f2070050 CR3: 000000011766c000 CR4: 00000000003526b0
Call Trace:
 <TASK>
 sscanf+0xe3/0x150 lib/vsprintf.c:3700
 split_huge_pages_write+0x3c7/0x1220 mm/huge_memory.c:4139
 full_proxy_write+0x125/0x1e0 fs/debugfs/file.c:328
 vfs_write+0x3c1/0xfd0 fs/read_write.c:682
 ksys_write+0x145/0x260 fs/read_write.c:737
 __do_sys_write fs/read_write.c:749 [inline]
 __se_sys_write fs/read_write.c:746 [inline]
 __x64_sys_write+0x7f/0x90 fs/read_write.c:746
 x64_sys_call+0x271c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f05f219e159
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:00007ffc69d37248 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f05f2425fa0 RCX: 00007f05f219e159
RDX: 0000000000000005 RSI: 0000200000000600 RDI: 0000000000000003
RBP: 00007f05f2235024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f05f2425fac R14: 00007f05f2425fa0 R15: 00007f05f2425fa0
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:vsscanf+0x18c/0x24b0 lib/vsprintf.c:3444
Code: 48 c7 c6 30 c0 e3 87 e8 a2 b8 e5 fb 41 83 fe 25 74 4d 45 85 f6 0f 84 a4 21 00 00 48 ff c3 48 89 5c 24 58 4c 89 f8 48 c1 e8 03 <42> 0f b6 04 28 84 c0 0f 85 8e 1b 00 00 41 0f b6 1f 45 0f b6 f6 44
RSP: 0018:ffffc90001aaf5a0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffffff86364c61 RCX: 0000000000000001
RDX: ffffffff85a1c41e RSI: ffffffff87e3c030 RDI: 0000000000000030
RBP: ffffc90001aaf6b0 R08: ffff888128c1a600 R09: 0000000000000002
R10: 0000000000000025 R11: 0000000000000000 R12: ffffffff86364c60
R13: dffffc0000000000 R14: 0000000000000030 R15: 0000000000000000
FS:  00005555740ad500(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f05f2070050 CR3: 000000011766c000 CR4: 00000000003526b0
----------------
Code disassembly (best guess):
   0:	48 c7 c6 30 c0 e3 87 	mov    $0xffffffff87e3c030,%rsi
   7:	e8 a2 b8 e5 fb       	call   0xfbe5b8ae
   c:	41 83 fe 25          	cmp    $0x25,%r14d
  10:	74 4d                	je     0x5f
  12:	45 85 f6             	test   %r14d,%r14d
  15:	0f 84 a4 21 00 00    	je     0x21bf
  1b:	48 ff c3             	inc    %rbx
  1e:	48 89 5c 24 58       	mov    %rbx,0x58(%rsp)
  23:	4c 89 f8             	mov    %r15,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 0f b6 04 28       	movzbl (%rax,%r13,1),%eax <-- trapping instruction
  2f:	84 c0                	test   %al,%al
  31:	0f 85 8e 1b 00 00    	jne    0x1bc5
  37:	41 0f b6 1f          	movzbl (%r15),%ebx
  3b:	45 0f b6 f6          	movzbl %r14b,%r14d
  3f:	44                   	rex.R

final repro crashed as (corrupted=false):
Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 0 UID: 0 PID: 383 Comm: syz.2.17 Not tainted syzkaller #0 4c7c6fabea823c7a50d4a31162f440126d0e7a76
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
RIP: 0010:vsscanf+0x18c/0x24b0 lib/vsprintf.c:3444
Code: 48 c7 c6 30 c0 e3 87 e8 a2 b8 e5 fb 41 83 fe 25 74 4d 45 85 f6 0f 84 a4 21 00 00 48 ff c3 48 89 5c 24 58 4c 89 f8 48 c1 e8 03 <42> 0f b6 04 28 84 c0 0f 85 8e 1b 00 00 41 0f b6 1f 45 0f b6 f6 44
RSP: 0018:ffffc90001aaf5a0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffffff86364c61 RCX: 0000000000000001
RDX: ffffffff85a1c41e RSI: ffffffff87e3c030 RDI: 0000000000000030
RBP: ffffc90001aaf6b0 R08: ffff888128c1a600 R09: 0000000000000002
R10: 0000000000000025 R11: 0000000000000000 R12: ffffffff86364c60
R13: dffffc0000000000 R14: 0000000000000030 R15: 0000000000000000
FS:  00005555740ad500(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f05f2070050 CR3: 000000011766c000 CR4: 00000000003526b0
Call Trace:
 <TASK>
 sscanf+0xe3/0x150 lib/vsprintf.c:3700
 split_huge_pages_write+0x3c7/0x1220 mm/huge_memory.c:4139
 full_proxy_write+0x125/0x1e0 fs/debugfs/file.c:328
 vfs_write+0x3c1/0xfd0 fs/read_write.c:682
 ksys_write+0x145/0x260 fs/read_write.c:737
 __do_sys_write fs/read_write.c:749 [inline]
 __se_sys_write fs/read_write.c:746 [inline]
 __x64_sys_write+0x7f/0x90 fs/read_write.c:746
 x64_sys_call+0x271c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:2
 do_syscall_x64 arch/x86/entry/common.c:47 [inline]
 do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
 entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7f05f219e159
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:00007ffc69d37248 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00007f05f2425fa0 RCX: 00007f05f219e159
RDX: 0000000000000005 RSI: 0000200000000600 RDI: 0000000000000003
RBP: 00007f05f2235024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f05f2425fac R14: 00007f05f2425fa0 R15: 00007f05f2425fa0
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:vsscanf+0x18c/0x24b0 lib/vsprintf.c:3444
Code: 48 c7 c6 30 c0 e3 87 e8 a2 b8 e5 fb 41 83 fe 25 74 4d 45 85 f6 0f 84 a4 21 00 00 48 ff c3 48 89 5c 24 58 4c 89 f8 48 c1 e8 03 <42> 0f b6 04 28 84 c0 0f 85 8e 1b 00 00 41 0f b6 1f 45 0f b6 f6 44
RSP: 0018:ffffc90001aaf5a0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffffff86364c61 RCX: 0000000000000001
RDX: ffffffff85a1c41e RSI: ffffffff87e3c030 RDI: 0000000000000030
RBP: ffffc90001aaf6b0 R08: ffff888128c1a600 R09: 0000000000000002
R10: 0000000000000025 R11: 0000000000000000 R12: ffffffff86364c60
R13: dffffc0000000000 R14: 0000000000000030 R15: 0000000000000000
FS:  00005555740ad500(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f05f2070050 CR3: 000000011766c000 CR4: 00000000003526b0
----------------
Code disassembly (best guess):
   0:	48 c7 c6 30 c0 e3 87 	mov    $0xffffffff87e3c030,%rsi
   7:	e8 a2 b8 e5 fb       	call   0xfbe5b8ae
   c:	41 83 fe 25          	cmp    $0x25,%r14d
  10:	74 4d                	je     0x5f
  12:	45 85 f6             	test   %r14d,%r14d
  15:	0f 84 a4 21 00 00    	je     0x21bf
  1b:	48 ff c3             	inc    %rbx
  1e:	48 89 5c 24 58       	mov    %rbx,0x58(%rsp)
  23:	4c 89 f8             	mov    %r15,%rax
  26:	48 c1 e8 03          	shr    $0x3,%rax
* 2a:	42 0f b6 04 28       	movzbl (%rax,%r13,1),%eax <-- trapping instruction
  2f:	84 c0                	test   %al,%al
  31:	0f 85 8e 1b 00 00    	jne    0x1bc5
  37:	41 0f b6 1f          	movzbl (%r15),%ebx
  3b:	45 0f b6 f6          	movzbl %r14b,%r14d
  3f:	44                   	rex.R