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BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x471/0x4b0
Read of size 2 at addr ffff888032f5d02a by task kworker/u8:2/5712

CPU: 0 UID: 0 PID: 5712 Comm: kworker/u8:2 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:check_preemption_disabled+0x3/0x120
Code: e3 8b 48 c7 c6 60 36 e3 8b eb 1c 66 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 <41> 56 53 48 83 ec 10 65 48 8b 05 be 8e 26 07 48 89 44 24 08 65 8b
RSP: 0018:ffffc90002f9f020 EFLAGS: 00000283
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000002
RDX: 0000000000000000 RSI: ffffffff8be33660 RDI: ffffffff8be33620
RBP: ffffffff8172c195 R08: 0000000000000000 R09: 0000000000000000
R10: ffffc90002f9f218 R11: ffffffff81ac3810 R12: 0000000000000002
R13: ffffffff8e139ee0 R14: 0000000000000000 R15: 0000000000000000
 rcu_is_watching+0x15/0xb0
 lock_acquire+0x5f/0x360
 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
 ib_free_port_attrs+0xc5/0x3b0
 rdma_dev_exit_net+0x1d8/0x340
 ops_undo_list+0x49a/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 26816:
 kasan_save_track+0x3e/0x80
 __kasan_kmalloc+0x93/0xb0
 __kmalloc_cache_noprof+0x230/0x3d0
 rxrpc_alloc_peer+0x7d/0x330
 rxrpc_service_prealloc_one+0x1f4/0xe20
 afs_charge_preallocation+0x394/0x4e0
 afs_open_socket+0x302/0x3a0
 afs_net_init+0x67d/0x880
 ops_init+0x35c/0x5c0
 setup_net+0x10c/0x320
 copy_net_ns+0x31b/0x4d0
 create_new_namespaces+0x3f3/0x720
 unshare_nsproxy_namespaces+0x11c/0x170
 ksys_unshare+0x4c8/0x8c0
 __x64_sys_unshare+0x38/0x50
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5712:
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x5b/0x80
 kfree+0x18e/0x440
 rxrpc_discard_prealloc+0x182/0x890
 rxrpc_listen+0x265/0x370
 afs_close_socket+0xa2/0x3a0
 afs_net_exit+0x60/0x100
 ops_undo_list+0x49a/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

The buggy address belongs to the object at ffff888032f5d000
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 42 bytes inside of
 freed 512-byte region [ffff888032f5d000, ffff888032f5d200)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888032f5ec00 pfn:0x32f5c
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 ffffea0000a41710 ffffea0000d66b10
raw: ffff888032f5ec00 000000000010000c 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88801a441c80 ffffea0000a41710 ffffea0000d66b10
head: ffff888032f5ec00 000000000010000c 00000000f5000000 0000000000000000
head: 00fff00000000002 ffffea0000cbd701 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 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 3589, tgid 3589 (kworker/u9:4), ts 47713757761, free_ts 0
 post_alloc_hook+0x240/0x2a0
 get_page_from_freelist+0x21e4/0x22c0
 __alloc_frozen_pages_noprof+0x181/0x370
 alloc_pages_mpol+0x232/0x4a0
 allocate_slab+0x8a/0x370
 ___slab_alloc+0xbeb/0x1410
 __kmalloc_noprof+0x305/0x4f0
 switchdev_deferred_enqueue+0x2d/0x240
 __set_ageing_time+0xc8/0x150
 br_stp_enable_port+0x13f/0x250
 br_port_carrier_check+0x301/0x3f0
 br_device_event+0x5fa/0x910
 notifier_call_chain+0x1b6/0x3e0
 netif_state_change+0x284/0x3a0
 linkwatch_do_dev+0x117/0x170
 __linkwatch_run_queue+0x56a/0x7e0
page_owner free stack trace missing

Memory state around the buggy address:
 ffff888032f5cf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888032f5cf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888032f5d000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff888032f5d080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888032f5d100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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