==================================================================
BUG: KASAN: null-ptr-deref in drop_buffers+0x65/0x4f0
Read of size 4 at addr 0000000000000060 by task kworker/0:6/5907

CPU: 0 UID: 0 PID: 5907 Comm: kworker/0:6 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: events_freezable_pwr_efficient disk_events_workfn
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250
 kasan_report+0x118/0x150
 kasan_check_range+0x2b0/0x2c0
 drop_buffers+0x65/0x4f0
 try_to_free_buffers+0x1e1/0x2d0
 shrink_folio_list+0x20ac/0x4cd0
 evict_folios+0x47f2/0x58b0
 try_to_shrink_lruvec+0x8a3/0xb50
 shrink_one+0x21b/0x7c0
 shrink_node+0x314e/0x3760
 do_try_to_free_pages+0x668/0x1960
 try_to_free_pages+0x8a2/0xdd0
 __alloc_pages_direct_reclaim+0x144/0x300
 __alloc_pages_slowpath+0x5ff/0xce0
 __alloc_frozen_pages_noprof+0x319/0x370
 alloc_pages_mpol+0x232/0x4a0
 alloc_pages_noprof+0xa9/0x190
 blk_rq_map_kern+0x339/0x650
 scsi_execute_cmd+0x2fb/0x1130
 sr_check_events+0x1b1/0xb30
 cdrom_check_events+0x64/0xe0
 disk_check_events+0x117/0x5b0
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
==================================================================
