------------[ cut here ]------------
sk->sk_forward_alloc
WARNING: net/ipv4/af_inet.c:162 at inet_sock_destruct+0x62d/0x740 net/ipv4/af_inet.c:162, CPU#0: syz.3.3540/20339
Modules linked in:
CPU: 0 UID: 0 PID: 20339 Comm: syz.3.3540 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
RIP: 0010:inet_sock_destruct+0x62d/0x740 net/ipv4/af_inet.c:162
Code: 0f 0b 90 e9 58 fe ff ff e8 d0 a3 a1 f7 90 0f 0b 90 e9 8b fe ff ff e8 c2 a3 a1 f7 90 0f 0b 90 e9 b1 fe ff ff e8 b4 a3 a1 f7 90 <0f> 0b 90 e9 d7 fe ff ff 89 f9 80 e1 07 80 c1 03 38 c1 0f 8c 95 fc
RSP: 0018:ffffc90000007d20 EFLAGS: 00010246
RAX: ffffffff8a2422ec RBX: dffffc0000000000 RCX: ffff8880785c0000
RDX: 0000000000000100 RSI: 0000000000000090 RDI: 0000000000000000
RBP: 0000000000000090 R08: ffff888030abe8a7 R09: 1ffff11006157d14
R10: dffffc0000000000 R11: ffffed1006157d15 R12: ffff888030abe600
R13: ffff888030abeb08 R14: ffff888030abe88c R15: ffffffff8fea6b00
FS:  0000000000000000(0000) GS:ffff888125298000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa595890d58 CR3: 000000000e74a000 CR4: 00000000003526f0
Call Trace:
 <IRQ>
 __sk_destruct+0x8d/0x9d0 net/core/sock.c:2352
 rcu_do_batch kernel/rcu/tree.c:2617 [inline]
 rcu_core+0x7cd/0x1070 kernel/rcu/tree.c:2869
 handle_softirqs+0x22a/0x840 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xca/0x220 kernel/softirq.c:735
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
 sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1061
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:unwind_next_frame+0x1457/0x2550 arch/x86/kernel/unwind_orc.c:-1
Code: 00 00 48 8b 44 24 08 0f b7 30 c1 ee 04 83 e6 0f 83 fe 08 0f 84 4b 05 00 00 83 fe 04 0f 84 e4 04 00 00 85 f6 0f 85 bf 06 00 00 <48> 8b 44 24 40 80 3c 28 00 74 08 48 89 df e8 66 13 ba 00 48 8b 3b
RSP: 0018:ffffc9000e1eeed8 EFLAGS: 00000246
RAX: ffffffff90d2a2fe RBX: ffffc9000e1eeff8 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff90d2a2fa
RBP: dffffc0000000000 R08: ffffc9000e1ef007 R09: 0000000000000000
R10: ffffc9000e1eeff8 R11: fffff52001c3de01 R12: ffffc9000e1ef328
R13: 1ffff92001c3ddf7 R14: ffffc9000e1eefa8 R15: 1ffffffff21a545f
 arch_stack_walk+0x11b/0x150 arch/x86/kernel/stacktrace.c:25
 stack_trace_save+0xa9/0x100 kernel/stacktrace.c:122
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2689 [inline]
 slab_free mm/slub.c:6250 [inline]
 kfree+0x1c5/0x640 mm/slub.c:6565
 genradix_free_recurse+0x5d/0xa0 lib/generic-radix-tree.c:204
 genradix_free_recurse+0x5d/0xa0 lib/generic-radix-tree.c:204
 sctp_stream_free+0x262/0x2a0 net/sctp/stream.c:191
 sctp_association_free+0x26d/0x7f0 net/sctp/associola.c:351
 sctp_cmd_delete_tcb net/sctp/sm_sideeffect.c:950 [inline]
 sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1336 [inline]
 sctp_side_effects net/sctp/sm_sideeffect.c:1204 [inline]
 sctp_do_sm+0x3f6b/0x5cf0 net/sctp/sm_sideeffect.c:1175
 sctp_primitive_SHUTDOWN+0x98/0xc0 net/sctp/primitive.c:89
 sctp_close+0x407/0x940 net/sctp/socket.c:1529
 inet_release+0x143/0x190 net/ipv4/af_inet.c:442
 __sock_release net/socket.c:722 [inline]
 sock_close+0xc3/0x240 net/socket.c:1514
 __fput+0x44f/0xa60 fs/file_table.c:510
 task_work_run+0x1d9/0x270 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x70f/0x22c0 kernel/exit.c:976
 do_group_exit+0x21b/0x2d0 kernel/exit.c:1119
 get_signal+0x1284/0x1330 kernel/signal.c:3037
 arch_do_signal_or_restart+0xbc/0x840 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop+0xa9/0x680 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x353/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd05a59ce59
Code: Unable to access opcode bytes at 0x7fd05a59ce2f.
RSP: 002b:00007fd05b4af028 EFLAGS: 00000246 ORIG_RAX: 0000000000000037
RAX: fffffffffffffe00 RBX: 00007fd05a816180 RCX: 00007fd05a59ce59
RDX: 000000000000006f RSI: 0000000000000084 RDI: 0000000000000007
RBP: 00007fd05a632d6f R08: 0000200000000640 R09: 0000000000000000
R10: 0000200000000200 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd05a816218 R14: 00007fd05a816180 R15: 00007ffef9b43f58
 </TASK>
----------------
Code disassembly (best guess):
   0:	00 00                	add    %al,(%rax)
   2:	48 8b 44 24 08       	mov    0x8(%rsp),%rax
   7:	0f b7 30             	movzwl (%rax),%esi
   a:	c1 ee 04             	shr    $0x4,%esi
   d:	83 e6 0f             	and    $0xf,%esi
  10:	83 fe 08             	cmp    $0x8,%esi
  13:	0f 84 4b 05 00 00    	je     0x564
  19:	83 fe 04             	cmp    $0x4,%esi
  1c:	0f 84 e4 04 00 00    	je     0x506
  22:	85 f6                	test   %esi,%esi
  24:	0f 85 bf 06 00 00    	jne    0x6e9
* 2a:	48 8b 44 24 40       	mov    0x40(%rsp),%rax <-- trapping instruction
  2f:	80 3c 28 00          	cmpb   $0x0,(%rax,%rbp,1)
  33:	74 08                	je     0x3d
  35:	48 89 df             	mov    %rbx,%rdi
  38:	e8 66 13 ba 00       	call   0xba13a3
  3d:	48 8b 3b             	mov    (%rbx),%rdi