Extracting prog: 2m9.977214677s
Minimizing prog: 7m58.991387539s
Simplifying prog options: 0s
Extracting C: 28.514793354s
Simplifying C: 18m53.837257616s


extracting reproducer from 24 programs
first checking the prog from the crash report
single: executing 1 programs separately with timeout 30s
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs: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:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
detailed listing:
executing program 0:
pipe2$9p(&(0x7f0000000140)={<r0=>0xffffffffffffffff, <r1=>0xffffffffffffffff}, 0x80800)
mount$9p_fd(0x0, &(0x7f0000000080)='./cgroup\x00', &(0x7f0000000100), 0x4, &(0x7f00000001c0)={'trans=fd,', {'rfdno', 0x3d, r0}, 0x2c, {'wfdno', 0x3d, r1}, 0x2c, {[{@directio}]}})

program crashed: UBSAN: shift-out-of-bounds in v9fs_get_tree
single: successfully extracted reproducer
found reproducer with 2 syscalls
minimizing guilty program
testing program (duration=45.771885196s, {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:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p
detailed listing:
executing program 0:
pipe2$9p(&(0x7f0000000140), 0x80800)

program did not crash
testing program (duration=45.771885196s, {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:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mount$9p_fd
detailed listing:
executing program 0:
mount$9p_fd(0x0, &(0x7f0000000080)='./cgroup\x00', &(0x7f0000000100), 0x4, &(0x7f00000001c0)={'trans=fd,', {}, 0x2c, {}, 0x2c, {[{@directio}]}})

program did not crash
testing program (duration=45.771885196s, {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:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
detailed listing:
executing program 0:
pipe2$9p(0x0, 0x80800)
mount$9p_fd(0x0, &(0x7f0000000080)='./cgroup\x00', &(0x7f0000000100), 0x4, &(0x7f00000001c0)={'trans=fd,', {}, 0x2c, {}, 0x2c, {[{@directio}]}})

program did not crash
testing program (duration=45.771885196s, {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:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
detailed listing:
executing program 0:
pipe2$9p(&(0x7f0000000140)={<r0=>0xffffffffffffffff, <r1=>0xffffffffffffffff}, 0x80800)
mount$9p_fd(0x0, 0x0, &(0x7f0000000100), 0x4, &(0x7f00000001c0)={'trans=fd,', {'rfdno', 0x3d, r0}, 0x2c, {'wfdno', 0x3d, r1}, 0x2c, {[{@directio}]}})

program did not crash
testing program (duration=45.771885196s, {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:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
detailed listing:
executing program 0:
pipe2$9p(&(0x7f0000000140)={<r0=>0xffffffffffffffff, <r1=>0xffffffffffffffff}, 0x80800)
mount$9p_fd(0x0, &(0x7f0000000080)='./cgroup\x00', 0x0, 0x4, &(0x7f00000001c0)={'trans=fd,', {'rfdno', 0x3d, r0}, 0x2c, {'wfdno', 0x3d, r1}, 0x2c, {[{@directio}]}})

program did not crash
testing program (duration=45.771885196s, {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:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
detailed listing:
executing program 0:
pipe2$9p(&(0x7f0000000140), 0x80800)
mount$9p_fd(0x0, &(0x7f0000000080)='./cgroup\x00', &(0x7f0000000100), 0x4, 0x0)

program did not crash
extracting C reproducer
testing compiled C program (duration=45.771885196s, {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:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
program crashed: UBSAN: shift-out-of-bounds in v9fs_get_tree
simplifying C reproducer
testing compiled C program (duration=45.771885196s, {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:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
program crashed: UBSAN: shift-out-of-bounds in v9fs_get_tree
testing compiled C program (duration=45.771885196s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
program did not crash
testing compiled C program (duration=45.771885196s, {Threaded:false 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:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
program crashed: UBSAN: shift-out-of-bounds in v9fs_get_tree
testing compiled C program (duration=45.771885196s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:true Sysctl:true Swap:false UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
program did not crash
testing compiled C program (duration=45.771885196s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
program crashed: UBSAN: shift-out-of-bounds in v9fs_get_tree
testing compiled C program (duration=45.771885196s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
program crashed: UBSAN: shift-out-of-bounds in v9fs_get_tree
testing compiled C program (duration=45.771885196s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
program crashed: UBSAN: shift-out-of-bounds in v9fs_get_tree
testing compiled C program (duration=45.771885196s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
program did not crash
testing compiled C program (duration=45.771885196s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:true BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
program crashed: UBSAN: shift-out-of-bounds in v9fs_get_tree
testing compiled C program (duration=45.771885196s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:true BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
program crashed: UBSAN: shift-out-of-bounds in v9fs_get_tree
testing compiled C program (duration=45.771885196s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:true BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
program crashed: UBSAN: shift-out-of-bounds in v9fs_get_tree
testing compiled C program (duration=45.771885196s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:true BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
program crashed: UBSAN: shift-out-of-bounds in v9fs_get_tree
testing compiled C program (duration=45.771885196s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:true BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
program crashed: UBSAN: shift-out-of-bounds in v9fs_get_tree
testing compiled C program (duration=45.771885196s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:true BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
program crashed: UBSAN: shift-out-of-bounds in v9fs_get_tree
testing compiled C program (duration=45.771885196s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:true BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:true UseTmpDir:true HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
program crashed: UBSAN: shift-out-of-bounds in v9fs_get_tree
testing compiled C program (duration=45.771885196s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:true BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:true HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
program crashed: UBSAN: shift-out-of-bounds in v9fs_get_tree
testing program (duration=45.771885196s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:true BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:true HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
detailed listing:
executing program 0:
pipe2$9p(&(0x7f0000000140)={<r0=>0xffffffffffffffff, <r1=>0xffffffffffffffff}, 0x80800)
mount$9p_fd(0x0, &(0x7f0000000080)='./cgroup\x00', &(0x7f0000000100), 0x4, &(0x7f00000001c0)={'trans=fd,', {'rfdno', 0x3d, r0}, 0x2c, {'wfdno', 0x3d, r1}, 0x2c, {[{@directio}]}})

program crashed: UBSAN: shift-out-of-bounds in v9fs_get_tree
validation run: crashed=true
testing program (duration=45.771885196s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:true BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:true HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
detailed listing:
executing program 0:
pipe2$9p(&(0x7f0000000140)={<r0=>0xffffffffffffffff, <r1=>0xffffffffffffffff}, 0x80800)
mount$9p_fd(0x0, &(0x7f0000000080)='./cgroup\x00', &(0x7f0000000100), 0x4, &(0x7f00000001c0)={'trans=fd,', {'rfdno', 0x3d, r0}, 0x2c, {'wfdno', 0x3d, r1}, 0x2c, {[{@directio}]}})

program crashed: UBSAN: shift-out-of-bounds in v9fs_get_tree
validation run: crashed=true
testing program (duration=45.771885196s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:true BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:true HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): pipe2$9p-mount$9p_fd
detailed listing:
executing program 0:
pipe2$9p(&(0x7f0000000140)={<r0=>0xffffffffffffffff, <r1=>0xffffffffffffffff}, 0x80800)
mount$9p_fd(0x0, &(0x7f0000000080)='./cgroup\x00', &(0x7f0000000100), 0x4, &(0x7f00000001c0)={'trans=fd,', {'rfdno', 0x3d, r0}, 0x2c, {'wfdno', 0x3d, r1}, 0x2c, {[{@directio}]}})

program crashed: UBSAN: shift-out-of-bounds in v9fs_get_tree
validation run: crashed=true
reproducing took 33m30.436696251s
repro crashed as (corrupted=false):
------------[ cut here ]------------
UBSAN: shift-out-of-bounds in fs/9p/vfs_super.c:57:22
shift exponent 32 is too large for 32-bit type 'int'
CPU: 1 UID: 0 PID: 6023 Comm: syz.0.17 Not tainted 6.17.0-rc2-next-20250818-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 ubsan_epilogue+0xa/0x40 lib/ubsan.c:233
 __ubsan_handle_shift_out_of_bounds+0x386/0x410 lib/ubsan.c:494
 v9fs_fill_super fs/9p/vfs_super.c:57 [inline]
 v9fs_get_tree+0x957/0xa90 fs/9p/vfs_super.c:125
 vfs_get_tree+0x8f/0x2b0 fs/super.c:1752
 do_new_mount+0x2a2/0xa30 fs/namespace.c:3810
 do_mount fs/namespace.c:4138 [inline]
 __do_sys_mount fs/namespace.c:4349 [inline]
 __se_sys_mount+0x317/0x410 fs/namespace.c:4326
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb874f8ebe9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffdbd92fc18 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fb8751b5fa0 RCX: 00007fb874f8ebe9
RDX: 0000200000000100 RSI: 0000200000000080 RDI: 0000000000000000
RBP: 00007fb875011e19 R08: 00002000000001c0 R09: 0000000000000000
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb8751b5fa0 R14: 00007fb8751b5fa0 R15: 0000000000000005
 </TASK>
---[ end trace ]---

final repro crashed as (corrupted=false):
------------[ cut here ]------------
UBSAN: shift-out-of-bounds in fs/9p/vfs_super.c:57:22
shift exponent 32 is too large for 32-bit type 'int'
CPU: 1 UID: 0 PID: 6023 Comm: syz.0.17 Not tainted 6.17.0-rc2-next-20250818-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 ubsan_epilogue+0xa/0x40 lib/ubsan.c:233
 __ubsan_handle_shift_out_of_bounds+0x386/0x410 lib/ubsan.c:494
 v9fs_fill_super fs/9p/vfs_super.c:57 [inline]
 v9fs_get_tree+0x957/0xa90 fs/9p/vfs_super.c:125
 vfs_get_tree+0x8f/0x2b0 fs/super.c:1752
 do_new_mount+0x2a2/0xa30 fs/namespace.c:3810
 do_mount fs/namespace.c:4138 [inline]
 __do_sys_mount fs/namespace.c:4349 [inline]
 __se_sys_mount+0x317/0x410 fs/namespace.c:4326
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb874f8ebe9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffdbd92fc18 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fb8751b5fa0 RCX: 00007fb874f8ebe9
RDX: 0000200000000100 RSI: 0000200000000080 RDI: 0000000000000000
RBP: 00007fb875011e19 R08: 00002000000001c0 R09: 0000000000000000
R10: 0000000000000004 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb8751b5fa0 R14: 00007fb8751b5fa0 R15: 0000000000000005
 </TASK>
---[ end trace ]---