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BUG: KASAN: slab-use-after-free in rose_timer_expiry+0x471/0x4b0
Read of size 2 at addr ffff8881285e742a by task syz-executor/5851

CPU: 1 UID: 0 PID: 5851 Comm: syz-executor 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
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:copy_page_from_iter+0x0/0x170
Code: ff 4c 89 f7 e8 61 ff 5c fd 4c 8b ac 24 90 00 00 00 e9 f5 e8 ff ff 0f 1f 40 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 55 41 57 41 56 41 55 41 54 53 48 83 ec 10 48 89 4c 24
RSP: 0018:ffffc9000387fad8 EFLAGS: 00000246
RAX: 1ffff110052bfdac RBX: ffff8880295fed60 RCX: ffffc9000387fd70
RDX: 0000000000001000 RSI: 0000000000000000 RDI: ffffea0004674500
RBP: ffffc9000387fc90 R08: ffffffff8fa38437 R09: 1ffffffff1f47086
R10: dffffc0000000000 R11: fffffbfff1f47087 R12: dffffc0000000000
R13: ffffea0004674500 R14: ffff8880295fed68 R15: 0000000000000dd9
 anon_pipe_write+0x99a/0x1360
 vfs_write+0x5c9/0xb30
 ksys_write+0x145/0x250
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f132478d69f
Code: 89 54 24 18 48 89 74 24 10 89 7c 24 08 e8 f9 92 02 00 48 8b 54 24 18 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 31 44 89 c7 48 89 44 24 08 e8 4c 93 02 00 48
RSP: 002b:00007ffdd7372620 EFLAGS: 00000293 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000002937 RCX: 00007f132478d69f
RDX: 0000000000000004 RSI: 00007ffdd73726e0 RDI: 00000000000000f8
RBP: 00007ffdd737268c R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000dd8
R13: 00000000000927c0 R14: 000000000009d520 R15: 00007ffdd73726e0
 </TASK>

Allocated by task 26954:
 kasan_save_track+0x3e/0x80
 __kasan_kmalloc+0x93/0xb0
 __kmalloc_cache_noprof+0x230/0x3d0
 rose_add_node+0x23a/0xde0
 rose_rt_ioctl+0xa48/0xfb0
 rose_ioctl+0x3ce/0x8b0
 sock_do_ioctl+0xdc/0x300
 sock_ioctl+0x576/0x790
 __se_sys_ioctl+0xfc/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 10263:
 kasan_save_track+0x3e/0x80
 kasan_save_free_info+0x46/0x50
 __kasan_slab_free+0x5b/0x80
 kfree+0x18e/0x440
 rose_rt_device_down+0x473/0x4c0
 rose_device_event+0x603/0x6a0
 notifier_call_chain+0x1b6/0x3e0
 __dev_notify_flags+0x18d/0x2e0
 netif_change_flags+0xe8/0x1a0
 dev_change_flags+0x130/0x260
 dev_ioctl+0x7b4/0x1150
 sock_do_ioctl+0x22c/0x300
 sock_ioctl+0x576/0x790
 __se_sys_ioctl+0xfc/0x170
 do_syscall_64+0xfa/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff8881285e7400
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 42 bytes inside of
 freed 512-byte region [ffff8881285e7400, ffff8881285e7600)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff8881285e6c00 pfn:0x1285e4
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x57ff00000000240(workingset|head|node=1|zone=2|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 057ff00000000240 ffff88801a441c80 ffffea0004694010 ffffea00043bd810
raw: ffff8881285e6c00 0000000000100005 00000000f5000000 0000000000000000
head: 057ff00000000240 ffff88801a441c80 ffffea0004694010 ffffea00043bd810
head: ffff8881285e6c00 0000000000100005 00000000f5000000 0000000000000000
head: 057ff00000000002 ffffea0004a17901 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 26938, tgid 26935 (syz.3.6124), ts 404657859043, free_ts 368734015291
 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_cache_noprof+0x296/0x3d0
 device_add+0xbe/0xb50
 netdev_register_kobject+0x178/0x310
 register_netdevice+0x126c/0x1ae0
 register_netdev+0x40/0x60
 loopback_net_init+0x75/0x150
 ops_init+0x35c/0x5c0
 setup_net+0x10c/0x320
 copy_net_ns+0x31b/0x4d0
 create_new_namespaces+0x3f3/0x720
page last free pid 24746 tgid 24745 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
 __kernfs_new_node+0xd7/0x7e0
 kernfs_new_node+0x102/0x210
 __kernfs_create_file+0x4b/0x2e0
 sysfs_add_file_mode_ns+0x238/0x300
 sysfs_merge_group+0x177/0x310
 dpm_sysfs_add+0xd2/0x270
 device_add+0x4d8/0xb50
 netdev_register_kobject+0x178/0x310

Memory state around the buggy address:
 ffff8881285e7300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8881285e7380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8881285e7400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff8881285e7480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881285e7500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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