Extracting prog: 3m29.52305318s
Minimizing prog: 8m26.571020426s
Simplifying prog options: 3m40.020899881s
Extracting C: 2m1.309372056s
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: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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_generic-syz_genetlink_get_family_id$ipvs-sendmsg$IPVS_CMD_GET_DEST-openat$comedi-ioctl$COMEDI_DEVCONFIG
detailed listing:
executing program 0:
r0 = socket$nl_generic(0x10, 0x3, 0x10)
syz_genetlink_get_family_id$ipvs(0x0, 0xffffffffffffffff)
sendmsg$IPVS_CMD_GET_DEST(r0, 0x0, 0x0)
r1 = openat$comedi(0xffffffffffffff9c, &(0x7f0000000040)='/dev/comedi0\x00', 0x800, 0x0)
ioctl$COMEDI_DEVCONFIG(r1, 0x40946400, &(0x7f0000000080)={'das16m1\x00', [0x2003, 0x4000003, 0x0, 0x400, 0x3a0b, 0x388, 0x871, 0x6, 0x7fffffff, 0x4800, 0x80000001, 0x6, 0x9, 0x0, 0x4, 0x0, 0xe, 0x0, 0x2, 0x2, 0x7, 0xffff1a8f, 0xe9, 0x9, 0xb, 0x7fe, 0x8, 0xb73c, 0x5, 0x1, 0x1]})

program did not crash
single: failed to extract reproducer
single: executing 1 programs separately with timeout 1m40s
testing program (duration=1m40s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_generic-syz_genetlink_get_family_id$ipvs-sendmsg$IPVS_CMD_GET_DEST-openat$comedi-ioctl$COMEDI_DEVCONFIG
detailed listing:
executing program 0:
r0 = socket$nl_generic(0x10, 0x3, 0x10)
syz_genetlink_get_family_id$ipvs(0x0, 0xffffffffffffffff)
sendmsg$IPVS_CMD_GET_DEST(r0, 0x0, 0x0)
r1 = openat$comedi(0xffffffffffffff9c, &(0x7f0000000040)='/dev/comedi0\x00', 0x800, 0x0)
ioctl$COMEDI_DEVCONFIG(r1, 0x40946400, &(0x7f0000000080)={'das16m1\x00', [0x2003, 0x4000003, 0x0, 0x400, 0x3a0b, 0x388, 0x871, 0x6, 0x7fffffff, 0x4800, 0x80000001, 0x6, 0x9, 0x0, 0x4, 0x0, 0xe, 0x0, 0x2, 0x2, 0x7, 0xffff1a8f, 0xe9, 0x9, 0xb, 0x7fe, 0x8, 0xb73c, 0x5, 0x1, 0x1]})

program crashed: UBSAN: shift-out-of-bounds in das16m1_attach
single: successfully extracted reproducer
found reproducer with 5 syscalls
minimizing guilty program
testing program (duration=1m40s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_generic-syz_genetlink_get_family_id$ipvs-sendmsg$IPVS_CMD_GET_DEST-openat$comedi
detailed listing:
executing program 0:
r0 = socket$nl_generic(0x10, 0x3, 0x10)
syz_genetlink_get_family_id$ipvs(0x0, 0xffffffffffffffff)
sendmsg$IPVS_CMD_GET_DEST(r0, 0x0, 0x0)
openat$comedi(0xffffffffffffff9c, &(0x7f0000000040)='/dev/comedi0\x00', 0x800, 0x0)

program crashed: WARNING: suspicious RCU usage in proc_sys_compare
testing program (duration=1m40s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_generic-syz_genetlink_get_family_id$ipvs-sendmsg$IPVS_CMD_GET_DEST
detailed listing:
executing program 0:
r0 = socket$nl_generic(0x10, 0x3, 0x10)
syz_genetlink_get_family_id$ipvs(0x0, 0xffffffffffffffff)
sendmsg$IPVS_CMD_GET_DEST(r0, 0x0, 0x0)

program crashed: WARNING: suspicious RCU usage in proc_sys_compare
testing program (duration=1m40s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_generic-syz_genetlink_get_family_id$ipvs
detailed listing:
executing program 0:
socket$nl_generic(0x10, 0x3, 0x10)
syz_genetlink_get_family_id$ipvs(0x0, 0xffffffffffffffff)

program crashed: WARNING: suspicious RCU usage in proc_sys_compare
testing program (duration=1m40s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_generic
detailed listing:
executing program 0:
socket$nl_generic(0x10, 0x3, 0x10)

program did not crash
testing program (duration=1m40s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_genetlink_get_family_id$ipvs
detailed listing:
executing program 0:
syz_genetlink_get_family_id$ipvs(0x0, 0xffffffffffffffff)

program did not crash
extracting C reproducer
testing compiled C program (duration=1m40s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_generic-syz_genetlink_get_family_id$ipvs
program did not crash
simplifying guilty program options
testing program (duration=1m40s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_generic-syz_genetlink_get_family_id$ipvs
detailed listing:
executing program 0:
socket$nl_generic(0x10, 0x3, 0x10)
syz_genetlink_get_family_id$ipvs(0x0, 0xffffffffffffffff)

program did not crash
testing program (duration=1m40s, {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:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_generic-syz_genetlink_get_family_id$ipvs
detailed listing:
executing program 0:
socket$nl_generic(0x10, 0x3, 0x10)
syz_genetlink_get_family_id$ipvs(0x0, 0xffffffffffffffff)

program did not crash
testing program (duration=1m40s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_generic-syz_genetlink_get_family_id$ipvs
detailed listing:
executing program 0:
socket$nl_generic(0x10, 0x3, 0x10)
syz_genetlink_get_family_id$ipvs(0x0, 0xffffffffffffffff)

program did not crash
validation run: crashed=false
testing program (duration=1m40s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_generic-syz_genetlink_get_family_id$ipvs
detailed listing:
executing program 0:
socket$nl_generic(0x10, 0x3, 0x10)
syz_genetlink_get_family_id$ipvs(0x0, 0xffffffffffffffff)

program did not crash
validation run: crashed=false
testing program (duration=1m40s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_generic-syz_genetlink_get_family_id$ipvs
detailed listing:
executing program 0:
socket$nl_generic(0x10, 0x3, 0x10)
syz_genetlink_get_family_id$ipvs(0x0, 0xffffffffffffffff)

program did not crash
validation run: crashed=false
testing program (duration=1m40s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_generic-syz_genetlink_get_family_id$ipvs
detailed listing:
executing program 0:
socket$nl_generic(0x10, 0x3, 0x10)
syz_genetlink_get_family_id$ipvs(0x0, 0xffffffffffffffff)

program did not crash
validation run: crashed=false
testing program (duration=1m40s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_generic-syz_genetlink_get_family_id$ipvs
detailed listing:
executing program 0:
socket$nl_generic(0x10, 0x3, 0x10)
syz_genetlink_get_family_id$ipvs(0x0, 0xffffffffffffffff)

program did not crash
validation run: crashed=false
testing program (duration=1m40s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_generic-syz_genetlink_get_family_id$ipvs
detailed listing:
executing program 0:
socket$nl_generic(0x10, 0x3, 0x10)
syz_genetlink_get_family_id$ipvs(0x0, 0xffffffffffffffff)

program did not crash
validation run: crashed=false
testing program (duration=1m40s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_generic-syz_genetlink_get_family_id$ipvs
detailed listing:
executing program 0:
socket$nl_generic(0x10, 0x3, 0x10)
syz_genetlink_get_family_id$ipvs(0x0, 0xffffffffffffffff)

program did not crash
validation run: crashed=false
testing program (duration=1m40s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_generic-syz_genetlink_get_family_id$ipvs
detailed listing:
executing program 0:
socket$nl_generic(0x10, 0x3, 0x10)
syz_genetlink_get_family_id$ipvs(0x0, 0xffffffffffffffff)

program crashed: WARNING: suspicious RCU usage in proc_sys_compare
validation run: crashed=true
testing program (duration=1m40s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_generic-syz_genetlink_get_family_id$ipvs
detailed listing:
executing program 0:
socket$nl_generic(0x10, 0x3, 0x10)
syz_genetlink_get_family_id$ipvs(0x0, 0xffffffffffffffff)

program crashed: WARNING: suspicious RCU usage in proc_sys_compare
validation run: crashed=true
testing program (duration=1m40s, {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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$nl_generic-syz_genetlink_get_family_id$ipvs
detailed listing:
executing program 0:
socket$nl_generic(0x10, 0x3, 0x10)
syz_genetlink_get_family_id$ipvs(0x0, 0xffffffffffffffff)

program did not crash
validation run: crashed=false
reproducing took 35m12.486625815s
repro crashed as (corrupted=false):
=============================
WARNING: suspicious RCU usage
6.16.0-rc4-next-20250704-syzkaller #0 Not tainted
-----------------------------
fs/proc/proc_sysctl.c:934 suspicious rcu_dereference_check() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
2 locks held by syz-executor/5956:
 #0: ffff88802fd2b160 (&sb->s_type->i_mutex_key#10){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:884 [inline]
 #0: ffff88802fd2b160 (&sb->s_type->i_mutex_key#10){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1824
 #1: ffff888073f996d8 (&lockref->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline]
 #1: ffff888073f996d8 (&lockref->lock){+.+.}-{3:3}, at: d_wait_lookup fs/dcache.c:2537 [inline]
 #1: ffff888073f996d8 (&lockref->lock){+.+.}-{3:3}, at: d_alloc_parallel+0xbe4/0x15e0 fs/dcache.c:2624

stack backtrace:
CPU: 0 UID: 0 PID: 5956 Comm: syz-executor Not tainted 6.16.0-rc4-next-20250704-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 lockdep_rcu_suspicious+0x140/0x1d0 kernel/locking/lockdep.c:6871
 proc_sys_compare+0x27d/0x2c0 fs/proc/proc_sysctl.c:934
 d_same_name fs/dcache.c:2179 [inline]
 d_alloc_parallel+0x1060/0x15e0 fs/dcache.c:2637
 __lookup_slow+0x116/0x3d0 fs/namei.c:1793
 lookup_slow+0x53/0x70 fs/namei.c:1825
 walk_component fs/namei.c:2129 [inline]
 link_path_walk+0x935/0xea0 fs/namei.c:2497
 path_openat+0x28c/0x3830 fs/namei.c:4042
 do_filp_open+0x1fa/0x410 fs/namei.c:4073
 do_sys_openat2+0x121/0x1c0 fs/open.c:1434
 do_sys_open fs/open.c:1449 [inline]
 __do_sys_openat fs/open.c:1465 [inline]
 __se_sys_openat fs/open.c:1460 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1460
 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: 0033:0x7fe775b8d290
Code: 48 89 44 24 20 75 93 44 89 54 24 0c e8 49 94 02 00 44 8b 54 24 0c 89 da 48 89 ee 41 89 c0 bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 38 44 89 c7 89 44 24 0c e8 9c 94 02 00 8b 44
RSP: 002b:00007fffca8ae700 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000080001 RCX: 00007fe775b8d290
RDX: 0000000000080001 RSI: 00007fffca8aecd0 RDI: 00000000ffffff9c
RBP: 00007fffca8aecd0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001
R13: 00007fffca8ae7a0 R14: 0000000000000009 R15: 0000000000000000
 </TASK>
chnl_net:caif_netlink_parms(): no params data found
bridge0: port 1(bridge_slave_0) entered blocking state
bridge0: port 1(bridge_slave_0) entered disabled state
bridge_slave_0: entered allmulticast mode
bridge_slave_0: entered promiscuous mode
bridge0: port 2(bridge_slave_1) entered blocking state
bridge0: port 2(bridge_slave_1) entered disabled state
bridge_slave_1: entered allmulticast mode
bridge_slave_1: entered promiscuous mode
bond0: (slave bond_slave_0): Enslaving as an active interface with an up link
bond0: (slave bond_slave_1): Enslaving as an active interface with an up link
team0: Port device team_slave_0 added
team0: Port device team_slave_1 added
batman_adv: batadv0: Adding interface: batadv_slave_0
batman_adv: batadv0: The MTU of interface batadv_slave_0 is too small (1500) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would solve the problem.
batman_adv: batadv0: Not using interface batadv_slave_0 (retrying later): interface not active
batman_adv: batadv0: Adding interface: batadv_slave_1
batman_adv: batadv0: The MTU of interface batadv_slave_1 is too small (1500) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would solve the problem.
batman_adv: batadv0: Not using interface batadv_slave_1 (retrying later): interface not active
hsr_slave_0: entered promiscuous mode
hsr_slave_1: entered promiscuous mode
debugfs: 'hsr0' already exists in 'hsr'
Cannot create hsr debugfs directory
netdevsim netdevsim1 netdevsim0: renamed from eth0
netdevsim netdevsim1 netdevsim1: renamed from eth1
netdevsim netdevsim1 netdevsim2: renamed from eth2
netdevsim netdevsim1 netdevsim3: renamed from eth3
8021q: adding VLAN 0 to HW filter on device bond0
8021q: adding VLAN 0 to HW filter on device team0
8021q: adding VLAN 0 to HW filter on device batadv0
veth0_vlan: entered promiscuous mode
veth1_vlan: entered promiscuous mode
veth0_macvtap: entered promiscuous mode
veth1_macvtap: entered promiscuous mode
batman_adv: batadv0: Interface activated: batadv_slave_0
batman_adv: batadv0: Interface activated: batadv_slave_1

final repro crashed as (corrupted=false):
=============================
WARNING: suspicious RCU usage
6.16.0-rc4-next-20250704-syzkaller #0 Not tainted
-----------------------------
fs/proc/proc_sysctl.c:934 suspicious rcu_dereference_check() usage!

other info that might help us debug this:


rcu_scheduler_active = 2, debug_locks = 1
2 locks held by syz-executor/5956:
 #0: ffff88802fd2b160 (&sb->s_type->i_mutex_key#10){++++}-{4:4}, at: inode_lock_shared include/linux/fs.h:884 [inline]
 #0: ffff88802fd2b160 (&sb->s_type->i_mutex_key#10){++++}-{4:4}, at: lookup_slow+0x46/0x70 fs/namei.c:1824
 #1: ffff888073f996d8 (&lockref->lock){+.+.}-{3:3}, at: spin_lock include/linux/spinlock.h:351 [inline]
 #1: ffff888073f996d8 (&lockref->lock){+.+.}-{3:3}, at: d_wait_lookup fs/dcache.c:2537 [inline]
 #1: ffff888073f996d8 (&lockref->lock){+.+.}-{3:3}, at: d_alloc_parallel+0xbe4/0x15e0 fs/dcache.c:2624

stack backtrace:
CPU: 0 UID: 0 PID: 5956 Comm: syz-executor Not tainted 6.16.0-rc4-next-20250704-syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 lockdep_rcu_suspicious+0x140/0x1d0 kernel/locking/lockdep.c:6871
 proc_sys_compare+0x27d/0x2c0 fs/proc/proc_sysctl.c:934
 d_same_name fs/dcache.c:2179 [inline]
 d_alloc_parallel+0x1060/0x15e0 fs/dcache.c:2637
 __lookup_slow+0x116/0x3d0 fs/namei.c:1793
 lookup_slow+0x53/0x70 fs/namei.c:1825
 walk_component fs/namei.c:2129 [inline]
 link_path_walk+0x935/0xea0 fs/namei.c:2497
 path_openat+0x28c/0x3830 fs/namei.c:4042
 do_filp_open+0x1fa/0x410 fs/namei.c:4073
 do_sys_openat2+0x121/0x1c0 fs/open.c:1434
 do_sys_open fs/open.c:1449 [inline]
 __do_sys_openat fs/open.c:1465 [inline]
 __se_sys_openat fs/open.c:1460 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1460
 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: 0033:0x7fe775b8d290
Code: 48 89 44 24 20 75 93 44 89 54 24 0c e8 49 94 02 00 44 8b 54 24 0c 89 da 48 89 ee 41 89 c0 bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 38 44 89 c7 89 44 24 0c e8 9c 94 02 00 8b 44
RSP: 002b:00007fffca8ae700 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000080001 RCX: 00007fe775b8d290
RDX: 0000000000080001 RSI: 00007fffca8aecd0 RDI: 00000000ffffff9c
RBP: 00007fffca8aecd0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000001
R13: 00007fffca8ae7a0 R14: 0000000000000009 R15: 0000000000000000
 </TASK>
chnl_net:caif_netlink_parms(): no params data found
bridge0: port 1(bridge_slave_0) entered blocking state
bridge0: port 1(bridge_slave_0) entered disabled state
bridge_slave_0: entered allmulticast mode
bridge_slave_0: entered promiscuous mode
bridge0: port 2(bridge_slave_1) entered blocking state
bridge0: port 2(bridge_slave_1) entered disabled state
bridge_slave_1: entered allmulticast mode
bridge_slave_1: entered promiscuous mode
bond0: (slave bond_slave_0): Enslaving as an active interface with an up link
bond0: (slave bond_slave_1): Enslaving as an active interface with an up link
team0: Port device team_slave_0 added
team0: Port device team_slave_1 added
batman_adv: batadv0: Adding interface: batadv_slave_0
batman_adv: batadv0: The MTU of interface batadv_slave_0 is too small (1500) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would solve the problem.
batman_adv: batadv0: Not using interface batadv_slave_0 (retrying later): interface not active
batman_adv: batadv0: Adding interface: batadv_slave_1
batman_adv: batadv0: The MTU of interface batadv_slave_1 is too small (1500) to handle the transport of batman-adv packets. Packets going over this interface will be fragmented on layer2 which could impact the performance. Setting the MTU to 1560 would solve the problem.
batman_adv: batadv0: Not using interface batadv_slave_1 (retrying later): interface not active
hsr_slave_0: entered promiscuous mode
hsr_slave_1: entered promiscuous mode
debugfs: 'hsr0' already exists in 'hsr'
Cannot create hsr debugfs directory
netdevsim netdevsim1 netdevsim0: renamed from eth0
netdevsim netdevsim1 netdevsim1: renamed from eth1
netdevsim netdevsim1 netdevsim2: renamed from eth2
netdevsim netdevsim1 netdevsim3: renamed from eth3
8021q: adding VLAN 0 to HW filter on device bond0
8021q: adding VLAN 0 to HW filter on device team0
8021q: adding VLAN 0 to HW filter on device batadv0
veth0_vlan: entered promiscuous mode
veth1_vlan: entered promiscuous mode
veth0_macvtap: entered promiscuous mode
veth1_macvtap: entered promiscuous mode
batman_adv: batadv0: Interface activated: batadv_slave_0
batman_adv: batadv0: Interface activated: batadv_slave_1