==================================================================
BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x471/0x4b0
Read of size 2 at addr ffff888039dcf82a by task kworker/u8:1/13

CPU: 1 UID: 0 PID: 13 Comm: kworker/u8:1 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: netns cleanup_net
Call Trace:
 <IRQ>
 dump_stack_lvl+0x189/0x250
 print_report+0xca/0x240
 kasan_report+0x118/0x150
 rose_timer_expiry+0x471/0x4b0
 call_timer_fn+0x17e/0x5f0
 __run_timer_base+0x61a/0x860
 run_timer_softirq+0xb7/0x180
 handle_softirqs+0x286/0x870
 __irq_exit_rcu+0xca/0x1f0
 irq_exit_rcu+0x9/0x30
 sysvec_apic_timer_interrupt+0xa6/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:lock_acquire+0x175/0x360
Code: 00 00 00 00 9c 8f 44 24 30 f7 44 24 30 00 02 00 00 0f 85 cd 00 00 00 f7 44 24 08 00 02 00 00 74 01 fb 65 48 8b 05 4b e3 02 11 <48> 3b 44 24 58 0f 85 f2 00 00 00 48 83 c4 60 5b 41 5c 41 5d 41 5e
RSP: 0018:ffffc90000106e58 EFLAGS: 00000206
RAX: 3d7396f68ac7c900 RBX: 0000000000000000 RCX: 3d7396f68ac7c900
RDX: 0000000000000000 RSI: ffffffff8dba5cdd RDI: ffffffff8be33300
RBP: ffffffff8172c195 R08: 0000000000000000 R09: ffffffff8172c195
R10: ffffc90000107018 R11: ffffffff81ac3910 R12: 0000000000000002
R13: ffffffff8e139ea0 R14: 0000000000000000 R15: 0000000000000246
 unwind_next_frame+0xc2/0x2390
 arch_stack_walk+0x11c/0x150
 stack_trace_save+0x9c/0xe0
 kasan_save_stack+0x3e/0x60
 kasan_record_aux_stack+0xbd/0xd0
 call_rcu+0x157/0x9c0
 kernfs_put+0x19e/0x480
 kernfs_remove_by_name_ns+0xb7/0x130
 sysfs_remove_group+0xfc/0x2c0
 sysfs_remove_groups+0x54/0xb0
 device_remove_attrs+0x208/0x260
 device_del+0x509/0x8e0
 unregister_netdevice_many_notify+0x1a6b/0x1ff0
 ops_undo_list+0x3dc/0x990
 cleanup_net+0x4c5/0x800
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Allocated by task 31226:
 kasan_save_track+0x3e/0x80
 __kasan_kmalloc+0x93/0xb0
 __kmalloc_cache_noprof+0x230/0x3d0
 __genradix_ptr_alloc+0x352/0x4a0
 __genradix_prealloc+0x44/0x90
 sctp_stream_init+0x14b/0x440
 sctp_association_new+0x10dd/0x25f0
 sctp_connect_new_asoc+0x2c5/0x690
 sctp_sendmsg+0x155c/0x2810
 __sock_sendmsg+0x19c/0x270
 __sys_sendto+0x3bd/0x520
 __x64_sys_sendto+0xde/0x100
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 31226:
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x5b/0x80
 kfree+0x18e/0x440
 genradix_free_recurse+0x5d/0xa0
 genradix_free_recurse+0x5d/0xa0
 sctp_stream_free+0xd5/0x110
 sctp_association_free+0x26d/0x7f0
 sctp_do_sm+0x3eba/0x5a20
 sctp_primitive_SHUTDOWN+0x98/0xc0
 sctp_close+0x409/0x900
 inet_release+0x144/0x190
 sock_close+0xc3/0x240
 __fput+0x44c/0xa70
 task_work_run+0x1d4/0x260
 get_signal+0x11ed/0x1340
 arch_do_signal_or_restart+0x9a/0x750
 exit_to_user_mode_loop+0x75/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888039dcf800
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 42 bytes inside of
 freed 512-byte region [ffff888039dcf800, ffff888039dcfa00)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888039dcd400 pfn:0x39dcc
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000240 ffff88801a441c80 ffffea0000c05d10 ffffea00009ff710
raw: ffff888039dcd400 0000000000100004 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88801a441c80 ffffea0000c05d10 ffffea00009ff710
head: ffff888039dcd400 0000000000100004 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea0000e77301 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x252800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_THISNODE), pid 23375, tgid 23375 (syz.0.5072), ts 430566179187, free_ts 416857448778
 post_alloc_hook+0x240/0x2a0
 get_page_from_freelist+0x21e4/0x22c0
 __alloc_frozen_pages_noprof+0x181/0x370
 allocate_slab+0x65/0x370
 ___slab_alloc+0xbeb/0x1410
 __kmalloc_node_noprof+0x2fd/0x4e0
 allocate_slab+0x16a/0x370
 ___slab_alloc+0xbeb/0x1410
 kmem_cache_alloc_noprof+0x283/0x3c0
 __send_signal_locked+0x22a/0xeb0
 force_sig_info_to_task+0x30c/0x590
 force_sig_fault+0xdc/0x130
 __bad_area_nosemaphore+0x3b3/0x780
 exc_page_fault+0x76/0xf0
 asm_exc_page_fault+0x26/0x30
page last free pid 22467 tgid 22467 stack trace:
 __free_frozen_pages+0xbc4/0xd30
 __put_partials+0x156/0x1a0
 put_cpu_partial+0x17c/0x250
 __slab_free+0x2d5/0x3c0
 qlist_free_all+0x97/0x140
 kasan_quarantine_reduce+0x148/0x160
 __kasan_slab_alloc+0x22/0x80
 kmem_cache_alloc_noprof+0x1c1/0x3c0
 vm_area_dup+0x2b/0x680
 __split_vma+0x1a9/0xa00
 vma_modify+0x12c3/0x1970
 vma_modify_flags+0x1e8/0x230
 mprotect_fixup+0x407/0x9c0
 do_mprotect_pkey+0x8cd/0xce0
 __x64_sys_mprotect+0x80/0x90
 do_syscall_64+0xfa/0x3b0

Memory state around the buggy address:
 ffff888039dcf700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888039dcf780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888039dcf800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff888039dcf880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888039dcf900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
