================================================================== 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:308 [inline] BUG: KASAN: out-of-bounds in end_buffer_read_sync+0xc3/0xd0 fs/buffer.c:161 Write of size 4 at addr ffffc90004bdf740 by task ksoftirqd/0/16 CPU: 0 PID: 16 Comm: ksoftirqd/0 Not tainted 6.6.99-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xac/0x200 mm/kasan/report.c:466 kasan_report+0x117/0x150 mm/kasan/report.c:579 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x288/0x290 mm/kasan/generic.c:187 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:308 [inline] end_buffer_read_sync+0xc3/0xd0 fs/buffer.c:161 end_bio_bh_io_sync+0xb7/0x110 fs/buffer.c:2784 req_bio_endio block/blk-mq.c:784 [inline] blk_update_request+0x597/0xe40 block/blk-mq.c:929 blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1056 blk_complete_reqs block/blk-mq.c:1136 [inline] blk_done_softirq+0x10b/0x160 block/blk-mq.c:1141 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xc7/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_call_function_single arch/x86/kernel/smp.c:262 [inline] sysvec_call_function_single+0xa1/0xc0 arch/x86/kernel/smp.c:262 asm_sysvec_call_function_single+0x1a/0x20 arch/x86/include/asm/idtentry.h:694 RIP: 0010:finish_task_switch+0x26a/0x920 kernel/sched/core.c:5255 Code: 0f 84 37 01 00 00 48 85 db 0f 85 56 01 00 00 0f 1f 44 00 00 4c 8b 75 d0 4c 89 e7 e8 60 6b 1a 09 e8 8b a4 2f 00 fb 4c 8b 65 c0 <49> 8d bc 24 f8 15 00 00 48 89 f8 48 c1 e8 03 42 0f b6 04 28 84 c0 RSP: 0018:ffffc90000157b98 EFLAGS: 00000282 RAX: ca97ace8bc9b7900 RBX: 0000000000000000 RCX: ca97ace8bc9b7900 RDX: dffffc0000000000 RSI: ffffffff8aaaba40 RDI: ffffffff8afc6680 RBP: ffffc90000157bf0 R08: ffffffff8e4a7cef R09: 1ffffffff1c94f9d R10: dffffc0000000000 R11: fffffbfff1c94f9e R12: ffff88801b265a00 R13: dffffc0000000000 R14: ffff88801b360000 R15: ffff8880b8e3cf08 context_switch kernel/sched/core.c:5384 [inline] __schedule+0x14ea/0x4580 kernel/sched/core.c:6700 schedule+0xbd/0x170 kernel/sched/core.c:6774 smpboot_thread_fn+0x710/0xa00 kernel/smpboot.c:160 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 The buggy address ffffc90004bdf740 belongs to a vmalloc virtual mapping The buggy address belongs to the physical page: page:ffffea00008c8b80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2322e memcg:ffff8880297e6402 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000000 0000000000000000 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000000000 00000001ffffffff ffff8880297e6402 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x102dc2(GFP_HIGHUSER|__GFP_NOWARN|__GFP_ZERO), pid 2, tgid 2 (kthreadd), ts 300847993017, free_ts 298032926004 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554 prep_new_page mm/page_alloc.c:1561 [inline] get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457 vm_area_alloc_pages mm/vmalloc.c:3089 [inline] __vmalloc_area_node mm/vmalloc.c:3158 [inline] __vmalloc_node_range+0x96b/0x1320 mm/vmalloc.c:3339 alloc_thread_stack_node kernel/fork.c:310 [inline] dup_task_struct+0x3d0/0x7c0 kernel/fork.c:1124 copy_process+0x549/0x3d70 kernel/fork.c:2331 kernel_clone+0x21b/0x840 kernel/fork.c:2914 kernel_thread+0x10d/0x160 kernel/fork.c:2976 create_kthread kernel/kthread.c:411 [inline] kthreadd+0x560/0x730 kernel/kthread.c:766 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1154 [inline] free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336 free_unref_page_list+0xbe/0x860 mm/page_alloc.c:2475 release_pages+0x1fa0/0x2220 mm/swap.c:1022 __folio_batch_release+0x71/0xe0 mm/swap.c:1042 folio_batch_release include/linux/pagevec.h:83 [inline] truncate_inode_pages_range+0x358/0xf00 mm/truncate.c:371 kill_bdev block/bdev.c:76 [inline] blkdev_flush_mapping+0x132/0x290 block/bdev.c:632 blkdev_put_whole block/bdev.c:663 [inline] blkdev_put+0x498/0x760 block/bdev.c:941 blkdev_release+0x84/0x90 block/fops.c:604 __fput+0x234/0x970 fs/file_table.c:384 task_work_run+0x1ce/0x250 kernel/task_work.c:239 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0x90b/0x23c0 kernel/exit.c:883 do_group_exit+0x21b/0x2d0 kernel/exit.c:1024 get_signal+0x12fc/0x1400 kernel/signal.c:2902 arch_do_signal_or_restart+0x96/0x780 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 Memory state around the buggy address: ffffc90004bdf600: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc90004bdf680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffffc90004bdf700: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffffc90004bdf780: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc90004bdf800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== ---------------- Code disassembly (best guess): 0: 0f 84 37 01 00 00 je 0x13d 6: 48 85 db test %rbx,%rbx 9: 0f 85 56 01 00 00 jne 0x165 f: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 14: 4c 8b 75 d0 mov -0x30(%rbp),%r14 18: 4c 89 e7 mov %r12,%rdi 1b: e8 60 6b 1a 09 call 0x91a6b80 20: e8 8b a4 2f 00 call 0x2fa4b0 25: fb sti 26: 4c 8b 65 c0 mov -0x40(%rbp),%r12 * 2a: 49 8d bc 24 f8 15 00 lea 0x15f8(%r12),%rdi <-- trapping instruction 31: 00 32: 48 89 f8 mov %rdi,%rax 35: 48 c1 e8 03 shr $0x3,%rax 39: 42 0f b6 04 28 movzbl (%rax,%r13,1),%eax 3e: 84 c0 test %al,%al