================================================================== BUG: KASAN: out-of-bounds in instrument_atomic_read_write include/linux/instrumented.h:96 [inline] BUG: KASAN: out-of-bounds in atomic_dec include/linux/atomic/atomic-instrumented.h:592 [inline] BUG: KASAN: out-of-bounds in put_bh include/linux/buffer_head.h:301 [inline] BUG: KASAN: out-of-bounds in end_buffer_read_sync+0xc1/0xd0 fs/buffer.c:161 Write of size 4 at addr ffffc9000481f660 by task ksoftirqd/1/23 CPU: 1 UID: 0 PID: 23 Comm: ksoftirqd/1 Not tainted 6.15.0-rc1-next-20250411-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0x16e/0x5b0 mm/kasan/report.c:521 kasan_report+0x143/0x180 mm/kasan/report.c:634 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x28f/0x2a0 mm/kasan/generic.c:189 instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_dec include/linux/atomic/atomic-instrumented.h:592 [inline] put_bh include/linux/buffer_head.h:301 [inline] end_buffer_read_sync+0xc1/0xd0 fs/buffer.c:161 end_bio_bh_io_sync+0xbf/0x120 fs/buffer.c:2748 blk_update_request+0x5e5/0x1160 block/blk-mq.c:983 blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1145 blk_complete_reqs block/blk-mq.c:1220 [inline] blk_done_softirq+0x100/0x150 block/blk-mq.c:1225 handle_softirqs+0x2d6/0x9b0 kernel/softirq.c:579 run_ksoftirqd+0xcf/0x130 kernel/softirq.c:968 smpboot_thread_fn+0x576/0xaa0 kernel/smpboot.c:164 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 The buggy address belongs to the virtual mapping at [ffffc90004818000, ffffc90004821000) created by: copy_process+0x5dc/0x3d10 kernel/fork.c:2276 The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x24f22 memcg:ffff888146319102 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff ffff888146319102 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x2dc2(GFP_KERNEL|__GFP_HIGHMEM|__GFP_ZERO|__GFP_NOWARN), pid 9331, tgid 9331 (syz.4.831), ts 541168123694, free_ts 540943480262 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1718 prep_new_page mm/page_alloc.c:1726 [inline] get_page_from_freelist+0x360a/0x37a0 mm/page_alloc.c:3700 __alloc_frozen_pages_noprof+0x211/0x5b0 mm/page_alloc.c:4982 alloc_pages_mpol+0x339/0x690 mm/mempolicy.c:2301 alloc_frozen_pages_noprof mm/mempolicy.c:2372 [inline] alloc_pages_noprof+0x121/0x190 mm/mempolicy.c:2392 vm_area_alloc_pages mm/vmalloc.c:3591 [inline] __vmalloc_area_node mm/vmalloc.c:3669 [inline] __vmalloc_node_range_noprof+0x9cb/0x1390 mm/vmalloc.c:3844 __vmalloc_node_noprof+0x80/0xa0 mm/vmalloc.c:3907 alloc_thread_stack_node kernel/fork.c:314 [inline] dup_task_struct+0x3f7/0x870 kernel/fork.c:1136 copy_process+0x5dc/0x3d10 kernel/fork.c:2276 kernel_clone+0x242/0x930 kernel/fork.c:2861 __do_sys_clone3 kernel/fork.c:3165 [inline] __se_sys_clone3+0x348/0x380 kernel/fork.c:3144 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 23 tgid 23 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1262 [inline] __free_frozen_pages+0xde8/0x10a0 mm/page_alloc.c:2725 pagetable_free include/linux/mm.h:3002 [inline] pagetable_dtor_free include/linux/mm.h:3100 [inline] __tlb_remove_table+0x36b/0x460 include/asm-generic/tlb.h:215 __tlb_remove_table_free mm/mmu_gather.c:227 [inline] tlb_remove_table_rcu+0x79/0xf0 mm/mmu_gather.c:290 rcu_do_batch kernel/rcu/tree.c:2546 [inline] rcu_core+0xaac/0x17a0 kernel/rcu/tree.c:2802 handle_softirqs+0x2d6/0x9b0 kernel/softirq.c:579 run_ksoftirqd+0xcf/0x130 kernel/softirq.c:968 smpboot_thread_fn+0x576/0xaa0 kernel/smpboot.c:164 kthread+0x7b7/0x940 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffffc9000481f500: 04 f2 04 f2 04 f2 00 f3 f3 f3 f3 f3 00 00 00 00 ffffc9000481f580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffffc9000481f600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffffc9000481f680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc9000481f700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================