==================================================================
BUG: KASAN: use-after-free in rose_timer_expiry+0x471/0x4b0
Read of size 2 at addr ffff888046fddc2a by task syz.0.6134/28355

CPU: 0 UID: 0 PID: 28355 Comm: syz.0.6134 Not tainted 6.16.0-rc5-syzkaller-00212-g9f735b6f8a77-dirty #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+0xd2/0x2b0
 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:rcu_lockdep_current_cpu_online+0x32/0x120
Code: 53 65 8b 0d b0 29 f8 10 b0 01 f7 c1 00 00 f0 00 0f 85 d5 00 00 00 83 3d 73 60 fa 0d 00 0f 84 c8 00 00 00 65 ff 05 8e 29 f8 10 <e8> 29 0b c6 09 89 c3 83 f8 08 0f 83 c7 00 00 00 49 be 00 00 00 00
RSP: 0018:ffffc90002edf2e8 EFLAGS: 00000282
RAX: 0000000000000001 RBX: 0000000000000000 RCX: 0000000080000001
RDX: 0000000000000000 RSI: ffffffff8be28c20 RDI: ffffffff8be28be0
RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff822d5eb7
R10: dffffc0000000000 R11: fffff940001bad11 R12: 00000000000375a2
R13: dffffc0000000000 R14: ffff88805fffa4d0 R15: 0000000000001000
 rcu_read_lock_held+0x1e/0x50
 page_ext_lookup+0xe7/0x180
 page_table_check_clear+0x278/0x700
 unmap_page_range+0x326e/0x41c0
 unmap_vmas+0x399/0x580
 exit_mmap+0x248/0xb50
 __mmput+0x118/0x420
 exit_mm+0x1da/0x2c0
 do_exit+0x648/0x22e0
 do_group_exit+0x21c/0x2d0
 get_signal+0x1286/0x1340
 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
RIP: 0033:0x7fdbc3f8e929
Code: Unable to access opcode bytes at 0x7fdbc3f8e8ff.
RSP: 002b:00007fdbc4db60e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: 0000000000000001 RBX: 00007fdbc41b5fa8 RCX: 00007fdbc3f8e929
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fdbc41b5fac
RBP: 00007fdbc41b5fa0 R08: 7fffffffffffffff R09: 0000000000000000
R10: ffffffffffffffff R11: 0000000000000246 R12: 00007fdbc41b5fac
R13: 0000000000000000 R14: 00007fff59140b50 R15: 00007fff59140c38
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888046fddf00 pfn:0x46fdd
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea00011bf788 ffffea00011bf708 0000000000000000
raw: ffff888046fddf00 0000000000110000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 27924, tgid 27922 (syz.0.6013), ts 503004588413, free_ts 506800991387
 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/0x3b0
 ___slab_alloc+0xbfc/0x1480
 kmem_cache_alloc_noprof+0x283/0x3c0
 __kernfs_new_node+0xd7/0x7e0
 kernfs_new_node+0x102/0x210
 __kernfs_create_file+0x4b/0x2e0
 sysfs_add_file_mode_ns+0x238/0x300
 internal_create_group+0x66d/0x1110
 sysfs_create_groups+0x59/0x120
 ib_setup_port_attrs+0x1407/0x2070
 add_one_compat_dev+0x3d6/0x5c0
 rdma_dev_init_net+0x1dd/0x270
page last free pid 28145 tgid 28143 stack trace:
 __free_frozen_pages+0xc71/0xe70
 __put_partials+0x161/0x1c0
 put_cpu_partial+0x17c/0x250
 __slab_free+0x2f7/0x400
 qlist_free_all+0x97/0x140
 kasan_quarantine_reduce+0x148/0x160
 __kasan_slab_alloc+0x22/0x80
 kmem_cache_alloc_node_noprof+0x1bb/0x3c0
 __alloc_skb+0x112/0x2d0
 alloc_skb_with_frags+0xca/0x890
 sock_alloc_send_pskb+0x857/0x990
 llc_ui_sendmsg+0x477/0xdd0
 __sock_sendmsg+0x21c/0x270
 sock_sendmsg+0x158/0x230
 splice_to_socket+0x8ff/0xf10
 direct_splice_actor+0x101/0x160

Memory state around the buggy address:
 ffff888046fddb00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888046fddb80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
>ffff888046fddc00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                                  ^
 ffff888046fddc80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888046fddd00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
==================================================================
