Extracting prog: 2m10.470465504s
Minimizing prog: 10m1.015817802s
Simplifying prog options: 3m37.849192192s
Extracting C: 37.204738211s
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:namespace 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$inet6-setsockopt$inet6_IPV6_ADDRFORM-socket$inet6-bind$inet6-connect$inet6
detailed listing:
executing program 0:
r0 = socket$inet6(0xa, 0x2, 0x0)
setsockopt$inet6_IPV6_ADDRFORM(r0, 0x29, 0x1, 0x0, 0x0)
r1 = socket$inet6(0xa, 0x1, 0x100)
bind$inet6(r1, &(0x7f0000000000)={0xa, 0x4e21, 0x0, @empty}, 0x1c)
connect$inet6(r1, &(0x7f0000000200)={0xa, 0x4e21, 0xfffffffd, @ipv4={'\x00', '\xff\xff', @dev={0xac, 0x14, 0x14, 0x3d}}}, 0x1c)

program crashed: possible deadlock in do_ipv6_setsockopt
single: successfully extracted reproducer
found reproducer with 5 syscalls
minimizing guilty program
testing program (duration=1m4.411531903s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace 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$inet6-setsockopt$inet6_IPV6_ADDRFORM-socket$inet6-bind$inet6
detailed listing:
executing program 0:
r0 = socket$inet6(0xa, 0x2, 0x0)
setsockopt$inet6_IPV6_ADDRFORM(r0, 0x29, 0x1, 0x0, 0x0)
r1 = socket$inet6(0xa, 0x1, 0x100)
bind$inet6(r1, &(0x7f0000000000)={0xa, 0x4e21, 0x0, @empty}, 0x1c)

program did not crash
testing program (duration=1m4.411531903s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace 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$inet6-setsockopt$inet6_IPV6_ADDRFORM-socket$inet6-connect$inet6
detailed listing:
executing program 0:
r0 = socket$inet6(0xa, 0x2, 0x0)
setsockopt$inet6_IPV6_ADDRFORM(r0, 0x29, 0x1, 0x0, 0x0)
r1 = socket$inet6(0xa, 0x1, 0x100)
connect$inet6(r1, &(0x7f0000000200)={0xa, 0x4e21, 0xfffffffd, @ipv4={'\x00', '\xff\xff', @dev={0xac, 0x14, 0x14, 0x3d}}}, 0x1c)

program did not crash
testing program (duration=1m4.411531903s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace 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$inet6-setsockopt$inet6_IPV6_ADDRFORM-bind$inet6-connect$inet6
detailed listing:
executing program 0:
r0 = socket$inet6(0xa, 0x2, 0x0)
setsockopt$inet6_IPV6_ADDRFORM(r0, 0x29, 0x1, 0x0, 0x0)
bind$inet6(0xffffffffffffffff, &(0x7f0000000000)={0xa, 0x4e21, 0x0, @empty}, 0x1c)
connect$inet6(0xffffffffffffffff, &(0x7f0000000200)={0xa, 0x4e21, 0xfffffffd, @ipv4={'\x00', '\xff\xff', @dev={0xac, 0x14, 0x14, 0x3d}}}, 0x1c)

program did not crash
testing program (duration=1m4.411531903s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace 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$inet6-socket$inet6-bind$inet6-connect$inet6
detailed listing:
executing program 0:
socket$inet6(0xa, 0x2, 0x0)
r0 = socket$inet6(0xa, 0x1, 0x100)
bind$inet6(r0, &(0x7f0000000000)={0xa, 0x4e21, 0x0, @empty}, 0x1c)
connect$inet6(r0, &(0x7f0000000200)={0xa, 0x4e21, 0xfffffffd, @ipv4={'\x00', '\xff\xff', @dev={0xac, 0x14, 0x14, 0x3d}}}, 0x1c)

program did not crash
testing program (duration=1m4.411531903s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace 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}}): setsockopt$inet6_IPV6_ADDRFORM-socket$inet6-bind$inet6-connect$inet6
detailed listing:
executing program 0:
setsockopt$inet6_IPV6_ADDRFORM(0xffffffffffffffff, 0x29, 0x1, 0x0, 0x0)
r0 = socket$inet6(0xa, 0x1, 0x100)
bind$inet6(r0, &(0x7f0000000000)={0xa, 0x4e21, 0x0, @empty}, 0x1c)
connect$inet6(r0, &(0x7f0000000200)={0xa, 0x4e21, 0xfffffffd, @ipv4={'\x00', '\xff\xff', @dev={0xac, 0x14, 0x14, 0x3d}}}, 0x1c)

program did not crash
testing program (duration=1m4.411531903s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace 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$inet6-setsockopt$inet6_IPV6_ADDRFORM-socket$inet6-bind$inet6-connect$inet6
detailed listing:
executing program 0:
r0 = socket$inet6(0xa, 0x2, 0x0)
setsockopt$inet6_IPV6_ADDRFORM(r0, 0x29, 0x1, 0x0, 0x0)
r1 = socket$inet6(0xa, 0x1, 0x100)
bind$inet6(r1, 0x0, 0x0)
connect$inet6(r1, &(0x7f0000000200)={0xa, 0x4e21, 0xfffffffd, @ipv4={'\x00', '\xff\xff', @dev={0xac, 0x14, 0x14, 0x3d}}}, 0x1c)

program did not crash
testing program (duration=1m4.411531903s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace 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$inet6-setsockopt$inet6_IPV6_ADDRFORM-socket$inet6-bind$inet6-connect$inet6
detailed listing:
executing program 0:
r0 = socket$inet6(0xa, 0x2, 0x0)
setsockopt$inet6_IPV6_ADDRFORM(r0, 0x29, 0x1, 0x0, 0x0)
r1 = socket$inet6(0xa, 0x1, 0x100)
bind$inet6(r1, &(0x7f0000000000)={0xa, 0x4e21, 0x0, @empty}, 0x1c)
connect$inet6(r1, 0x0, 0x0)

program did not crash
extracting C reproducer
testing compiled C program (duration=1m4.411531903s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace 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$inet6-setsockopt$inet6_IPV6_ADDRFORM-socket$inet6-bind$inet6-connect$inet6
program crashed: possible deadlock in smc_vlan_by_tcpsk
a never seen crash title: possible deadlock in smc_vlan_by_tcpsk, ignore
simplifying guilty program options
testing program (duration=1m4.411531903s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:namespace SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): socket$inet6-setsockopt$inet6_IPV6_ADDRFORM-socket$inet6-bind$inet6-connect$inet6
detailed listing:
executing program 0:
r0 = socket$inet6(0xa, 0x2, 0x0)
setsockopt$inet6_IPV6_ADDRFORM(r0, 0x29, 0x1, 0x0, 0x0)
r1 = socket$inet6(0xa, 0x1, 0x100)
bind$inet6(r1, &(0x7f0000000000)={0xa, 0x4e21, 0x0, @empty}, 0x1c)
connect$inet6(r1, &(0x7f0000000200)={0xa, 0x4e21, 0xfffffffd, @ipv4={'\x00', '\xff\xff', @dev={0xac, 0x14, 0x14, 0x3d}}}, 0x1c)

program crashed: possible deadlock in smc_vlan_by_tcpsk
a never seen crash title: possible deadlock in smc_vlan_by_tcpsk, ignore
testing program (duration=1m4.411531903s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:namespace 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$inet6-setsockopt$inet6_IPV6_ADDRFORM-socket$inet6-bind$inet6-connect$inet6
detailed listing:
executing program 0:
r0 = socket$inet6(0xa, 0x2, 0x0)
setsockopt$inet6_IPV6_ADDRFORM(r0, 0x29, 0x1, 0x0, 0x0)
r1 = socket$inet6(0xa, 0x1, 0x100)
bind$inet6(r1, &(0x7f0000000000)={0xa, 0x4e21, 0x0, @empty}, 0x1c)
connect$inet6(r1, &(0x7f0000000200)={0xa, 0x4e21, 0xfffffffd, @ipv4={'\x00', '\xff\xff', @dev={0xac, 0x14, 0x14, 0x3d}}}, 0x1c)

program crashed: possible deadlock in smc_vlan_by_tcpsk
a never seen crash title: possible deadlock in smc_vlan_by_tcpsk, ignore
testing program (duration=1m4.411531903s, {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: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$inet6-setsockopt$inet6_IPV6_ADDRFORM-socket$inet6-bind$inet6-connect$inet6
detailed listing:
executing program 0:
r0 = socket$inet6(0xa, 0x2, 0x0)
setsockopt$inet6_IPV6_ADDRFORM(r0, 0x29, 0x1, 0x0, 0x0)
r1 = socket$inet6(0xa, 0x1, 0x100)
bind$inet6(r1, &(0x7f0000000000)={0xa, 0x4e21, 0x0, @empty}, 0x1c)
connect$inet6(r1, &(0x7f0000000200)={0xa, 0x4e21, 0xfffffffd, @ipv4={'\x00', '\xff\xff', @dev={0xac, 0x14, 0x14, 0x3d}}}, 0x1c)

program crashed: possible deadlock in smc_vlan_by_tcpsk
a never seen crash title: possible deadlock in smc_vlan_by_tcpsk, ignore
reproducing took 16m26.540229049s
repro crashed as (corrupted=false):
======================================================
WARNING: possible circular locking dependency detected
6.14.0-rc4-syzkaller-00090-gdd83757f6e68 #0 Not tainted
------------------------------------------------------
syz.3.19/6023 is trying to acquire lock:
ffff888027863558 (sk_lock-AF_INET6){+.+.}-{0:0}, at: do_ipv6_setsockopt+0xbb9/0x35b0 net/ipv6/ipv6_sockglue.c:567

but task is already holding lock:
ffffffff8fed51c8 (rtnl_mutex){+.+.}-{4:4}, at: do_ipv6_setsockopt+0x9a1/0x35b0 net/ipv6/ipv6_sockglue.c:566

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (rtnl_mutex){+.+.}-{4:4}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
       __mutex_lock_common kernel/locking/mutex.c:585 [inline]
       __mutex_lock+0x19c/0x1010 kernel/locking/mutex.c:730
       smc_vlan_by_tcpsk+0x399/0x4e0 net/smc/smc_core.c:1908
       __smc_connect+0x296/0x1910 net/smc/af_smc.c:1520
       smc_connect+0x868/0xde0 net/smc/af_smc.c:1696
       __sys_connect_file net/socket.c:2045 [inline]
       __sys_connect+0x288/0x2d0 net/socket.c:2064
       __do_sys_connect net/socket.c:2070 [inline]
       __se_sys_connect net/socket.c:2067 [inline]
       __x64_sys_connect+0x7a/0x90 net/socket.c:2067
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (sk_lock-AF_INET6){+.+.}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3163 [inline]
       check_prevs_add kernel/locking/lockdep.c:3282 [inline]
       validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3906
       __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
       lock_sock_nested+0x48/0x100 net/core/sock.c:3645
       do_ipv6_setsockopt+0xbb9/0x35b0 net/ipv6/ipv6_sockglue.c:567
       ipv6_setsockopt+0x5d/0x170 net/ipv6/ipv6_sockglue.c:993
       do_sock_setsockopt+0x3af/0x720 net/socket.c:2303
       __sys_setsockopt net/socket.c:2328 [inline]
       __do_sys_setsockopt net/socket.c:2334 [inline]
       __se_sys_setsockopt net/socket.c:2331 [inline]
       __x64_sys_setsockopt+0x1ee/0x280 net/socket.c:2331
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(rtnl_mutex);
                               lock(sk_lock-AF_INET6);
                               lock(rtnl_mutex);
  lock(sk_lock-AF_INET6);

 *** DEADLOCK ***

1 lock held by syz.3.19/6023:
 #0: ffffffff8fed51c8 (rtnl_mutex){+.+.}-{4:4}, at: do_ipv6_setsockopt+0x9a1/0x35b0 net/ipv6/ipv6_sockglue.c:566

stack backtrace:
CPU: 0 UID: 0 PID: 6023 Comm: syz.3.19 Not tainted 6.14.0-rc4-syzkaller-00090-gdd83757f6e68 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2076
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2208
 check_prev_add kernel/locking/lockdep.c:3163 [inline]
 check_prevs_add kernel/locking/lockdep.c:3282 [inline]
 validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3906
 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
 lock_sock_nested+0x48/0x100 net/core/sock.c:3645
 do_ipv6_setsockopt+0xbb9/0x35b0 net/ipv6/ipv6_sockglue.c:567
 ipv6_setsockopt+0x5d/0x170 net/ipv6/ipv6_sockglue.c:993
 do_sock_setsockopt+0x3af/0x720 net/socket.c:2303
 __sys_setsockopt net/socket.c:2328 [inline]
 __do_sys_setsockopt net/socket.c:2334 [inline]
 __se_sys_setsockopt net/socket.c:2331 [inline]
 __x64_sys_setsockopt+0x1ee/0x280 net/socket.c:2331
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb4c8b8d169
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:00007fb4c99e1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007fb4c8da5fa0 RCX: 00007fb4c8b8d169
RDX: 0000000000000001 RSI: 0000000000000029 RDI: 0000000000000003
RBP: 00007fb4c8c0e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fb4c8da5fa0 R15: 00007fb4c8ecfa28
 </TASK>

final repro crashed as (corrupted=false):
======================================================
WARNING: possible circular locking dependency detected
6.14.0-rc4-syzkaller-00090-gdd83757f6e68 #0 Not tainted
------------------------------------------------------
syz.3.19/6023 is trying to acquire lock:
ffff888027863558 (sk_lock-AF_INET6){+.+.}-{0:0}, at: do_ipv6_setsockopt+0xbb9/0x35b0 net/ipv6/ipv6_sockglue.c:567

but task is already holding lock:
ffffffff8fed51c8 (rtnl_mutex){+.+.}-{4:4}, at: do_ipv6_setsockopt+0x9a1/0x35b0 net/ipv6/ipv6_sockglue.c:566

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (rtnl_mutex){+.+.}-{4:4}:
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
       __mutex_lock_common kernel/locking/mutex.c:585 [inline]
       __mutex_lock+0x19c/0x1010 kernel/locking/mutex.c:730
       smc_vlan_by_tcpsk+0x399/0x4e0 net/smc/smc_core.c:1908
       __smc_connect+0x296/0x1910 net/smc/af_smc.c:1520
       smc_connect+0x868/0xde0 net/smc/af_smc.c:1696
       __sys_connect_file net/socket.c:2045 [inline]
       __sys_connect+0x288/0x2d0 net/socket.c:2064
       __do_sys_connect net/socket.c:2070 [inline]
       __se_sys_connect net/socket.c:2067 [inline]
       __x64_sys_connect+0x7a/0x90 net/socket.c:2067
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (sk_lock-AF_INET6){+.+.}-{0:0}:
       check_prev_add kernel/locking/lockdep.c:3163 [inline]
       check_prevs_add kernel/locking/lockdep.c:3282 [inline]
       validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3906
       __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228
       lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
       lock_sock_nested+0x48/0x100 net/core/sock.c:3645
       do_ipv6_setsockopt+0xbb9/0x35b0 net/ipv6/ipv6_sockglue.c:567
       ipv6_setsockopt+0x5d/0x170 net/ipv6/ipv6_sockglue.c:993
       do_sock_setsockopt+0x3af/0x720 net/socket.c:2303
       __sys_setsockopt net/socket.c:2328 [inline]
       __do_sys_setsockopt net/socket.c:2334 [inline]
       __se_sys_setsockopt net/socket.c:2331 [inline]
       __x64_sys_setsockopt+0x1ee/0x280 net/socket.c:2331
       do_syscall_x64 arch/x86/entry/common.c:52 [inline]
       do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(rtnl_mutex);
                               lock(sk_lock-AF_INET6);
                               lock(rtnl_mutex);
  lock(sk_lock-AF_INET6);

 *** DEADLOCK ***

1 lock held by syz.3.19/6023:
 #0: ffffffff8fed51c8 (rtnl_mutex){+.+.}-{4:4}, at: do_ipv6_setsockopt+0x9a1/0x35b0 net/ipv6/ipv6_sockglue.c:566

stack backtrace:
CPU: 0 UID: 0 PID: 6023 Comm: syz.3.19 Not tainted 6.14.0-rc4-syzkaller-00090-gdd83757f6e68 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120
 print_circular_bug+0x13a/0x1b0 kernel/locking/lockdep.c:2076
 check_noncircular+0x36a/0x4a0 kernel/locking/lockdep.c:2208
 check_prev_add kernel/locking/lockdep.c:3163 [inline]
 check_prevs_add kernel/locking/lockdep.c:3282 [inline]
 validate_chain+0x18ef/0x5920 kernel/locking/lockdep.c:3906
 __lock_acquire+0x1397/0x2100 kernel/locking/lockdep.c:5228
 lock_acquire+0x1ed/0x550 kernel/locking/lockdep.c:5851
 lock_sock_nested+0x48/0x100 net/core/sock.c:3645
 do_ipv6_setsockopt+0xbb9/0x35b0 net/ipv6/ipv6_sockglue.c:567
 ipv6_setsockopt+0x5d/0x170 net/ipv6/ipv6_sockglue.c:993
 do_sock_setsockopt+0x3af/0x720 net/socket.c:2303
 __sys_setsockopt net/socket.c:2328 [inline]
 __do_sys_setsockopt net/socket.c:2334 [inline]
 __se_sys_setsockopt net/socket.c:2331 [inline]
 __x64_sys_setsockopt+0x1ee/0x280 net/socket.c:2331
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb4c8b8d169
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:00007fb4c99e1038 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007fb4c8da5fa0 RCX: 00007fb4c8b8d169
RDX: 0000000000000001 RSI: 0000000000000029 RDI: 0000000000000003
RBP: 00007fb4c8c0e2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fb4c8da5fa0 R15: 00007fb4c8ecfa28
 </TASK>