================================================================== BUG: KASAN: slab-out-of-bounds in __bitmap_clear+0x155/0x180 lib/bitmap.c:395 Read of size 8 at addr ffff88816ced7cd0 by task kworker/0:1/10 CPU: 0 UID: 0 PID: 10 Comm: kworker/0:1 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: xfs-conv/loop0 xfs_end_io Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 __bitmap_clear+0x155/0x180 lib/bitmap.c:395 bitmap_clear include/linux/bitmap.h:496 [inline] ifs_clear_range_atomic fs/iomap/buffered-io.c:241 [inline] iomap_clear_range_atomic+0x25c/0x630 fs/iomap/buffered-io.c:268 iomap_finish_folio_write+0x2f0/0x410 fs/iomap/buffered-io.c:1971 iomap_finish_ioend_buffered+0x223/0x5e0 fs/iomap/ioend.c:58 iomap_finish_ioends+0x116/0x2b0 fs/iomap/ioend.c:295 xfs_end_ioend+0x50b/0x690 fs/xfs/xfs_aops.c:168 xfs_end_io+0x253/0x2d0 fs/xfs/xfs_aops.c:205 process_one_work+0x94a/0x15d0 kernel/workqueue.c:3267 process_scheduled_works kernel/workqueue.c:3350 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3431 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 5952: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:397 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:414 kasan_kmalloc include/linux/kasan.h:262 [inline] __do_kmalloc_node mm/slub.c:5672 [inline] __kmalloc_noprof+0x41d/0x800 mm/slub.c:5684 kmalloc_noprof include/linux/slab.h:961 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] ifs_alloc+0x1e4/0x530 fs/iomap/buffered-io.c:356 iomap_writeback_folio+0x81c/0x26a0 fs/iomap/buffered-io.c:2084 iomap_writepages+0x162/0x2d0 fs/iomap/buffered-io.c:2168 xfs_vm_writepages+0x28a/0x300 fs/xfs/xfs_aops.c:701 do_writepages+0x32e/0x550 mm/page-writeback.c:2598 filemap_writeback mm/filemap.c:387 [inline] filemap_fdatawrite_range mm/filemap.c:412 [inline] file_write_and_wait_range+0x23e/0x340 mm/filemap.c:786 xfs_file_fsync+0x195/0x800 fs/xfs/xfs_file.c:137 generic_write_sync include/linux/fs.h:2639 [inline] xfs_file_buffered_write+0x723/0x8a0 fs/xfs/xfs_file.c:1015 do_iter_readv_writev+0x623/0x8c0 fs/read_write.c:-1 vfs_writev+0x31a/0x960 fs/read_write.c:1057 do_pwritev fs/read_write.c:1153 [inline] __do_sys_pwritev2 fs/read_write.c:1211 [inline] __se_sys_pwritev2+0x179/0x290 fs/read_write.c:1202 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88816ced7c80 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 0 bytes to the right of allocated 80-byte region [ffff88816ced7c80, ffff88816ced7cd0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x16ced7 flags: 0x57ff00000000000(node=1|zone=2|lastcpupid=0x7ff) page_type: f5(slab) raw: 057ff00000000000 ffff888100041280 dead000000000100 dead000000000122 raw: 0000000000000000 0000000080200020 00000000f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x252800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_THISNODE), pid 1, tgid 1 (swapper/0), ts 12041529441, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1851 prep_new_page mm/page_alloc.c:1859 [inline] get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3920 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5209 alloc_slab_page mm/slub.c:3086 [inline] allocate_slab+0x71/0x350 mm/slub.c:3257 new_slab mm/slub.c:3311 [inline] ___slab_alloc+0xf56/0x1990 mm/slub.c:4671 __slab_alloc+0x65/0x100 mm/slub.c:4794 __slab_alloc_node mm/slub.c:4870 [inline] slab_alloc_node mm/slub.c:5266 [inline] __kmalloc_cache_node_noprof+0x4b7/0x6f0 mm/slub.c:5799 kmalloc_node_noprof include/linux/slab.h:983 [inline] alloc_node_nr_active kernel/workqueue.c:4908 [inline] __alloc_workqueue+0x6a9/0x1b80 kernel/workqueue.c:5762 alloc_workqueue_noprof+0xd4/0x210 kernel/workqueue.c:5822 nbd_dev_add+0x4f1/0xae0 drivers/block/nbd.c:1961 nbd_init+0x168/0x1f0 drivers/block/nbd.c:2691 do_one_initcall+0x25a/0x860 init/main.c:1378 do_initcall_level+0x104/0x190 init/main.c:1440 do_initcalls+0x59/0xa0 init/main.c:1456 kernel_init_freeable+0x334/0x4b0 init/main.c:1688 kernel_init+0x1d/0x1d0 init/main.c:1578 page_owner free stack trace missing Memory state around the buggy address: ffff88816ced7b80: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ffff88816ced7c00: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc >ffff88816ced7c80: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ^ ffff88816ced7d00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff88816ced7d80: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ==================================================================