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BUG: KASAN: use-after-free in copy_page_from_iter_atomic+0x9c7/0x1540 lib/iov_iter.c:922
Read of size 4096 at addr ffff88808c6fb000 by task kworker/u4:1/10

CPU: 0 PID: 10 Comm: kworker/u4:1 Not tainted 5.15.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: loop4 loop_rootcg_workfn
Call Trace:
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1dc/0x2d8 lib/dump_stack.c:106
 print_address_description+0x66/0x3e0 mm/kasan/report.c:256
 __kasan_report mm/kasan/report.c:442 [inline]
 kasan_report+0x19a/0x1f0 mm/kasan/report.c:459
 kasan_check_range+0x2b5/0x2f0 mm/kasan/generic.c:189
 memcpy+0x25/0x60 mm/kasan/shadow.c:65
 copy_page_from_iter_atomic+0x9c7/0x1540 lib/iov_iter.c:922
 generic_perform_write+0x356/0x600 mm/filemap.c:3778
 __generic_file_write_iter+0x243/0x4f0 mm/filemap.c:3897
 generic_file_write_iter+0xa7/0x1b0 mm/filemap.c:3929
 do_iter_readv_writev+0x54f/0x740
 do_iter_write+0x21e/0x7b0 fs/read_write.c:855
 lo_write_bvec+0x277/0x6f0 drivers/block/loop.c:328
 lo_write_simple drivers/block/loop.c:350 [inline]
 do_req_filebacked drivers/block/loop.c:668 [inline]
 loop_handle_cmd drivers/block/loop.c:2201 [inline]
 loop_process_work+0x2242/0x2d40 drivers/block/loop.c:2241
 process_one_work+0x853/0x1140 kernel/workqueue.c:2297
 worker_thread+0xac1/0x1320 kernel/workqueue.c:2444
 kthread+0x453/0x480 kernel/kthread.c:319
 ret_from_fork+0x1f/0x30

The buggy address belongs to the page:
page:ffffea000231bec0 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x8c6fb
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000000 ffffea0002360888 ffffea0001e3db48 0000000000000000
raw: 0000000000000000 0000000000000000 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 0xdc0(GFP_KERNEL|__GFP_ZERO), pid 24376, ts 1674553208190, free_ts 1674711698112
 prep_new_page mm/page_alloc.c:2424 [inline]
 get_page_from_freelist+0x779/0xa30 mm/page_alloc.c:4153
 __alloc_pages+0x255/0x580 mm/page_alloc.c:5375
 lbmLogInit fs/jfs/jfs_logmgr.c:1824 [inline]
 lmLogInit+0x37c/0x1f50 fs/jfs/jfs_logmgr.c:1278
 open_inline_log fs/jfs/jfs_logmgr.c:1183 [inline]
 lmLogOpen+0x505/0x1190 fs/jfs/jfs_logmgr.c:1077
 jfs_mount_rw+0xe3/0x680 fs/jfs/jfs_mount.c:260
 jfs_fill_super+0x6a9/0xcf0 fs/jfs/super.c:570
 mount_bdev+0x26c/0x3a0 fs/super.c:1368
 legacy_get_tree+0xea/0x180 fs/fs_context.c:610
 vfs_get_tree+0x86/0x270 fs/super.c:1498
 do_new_mount fs/namespace.c:2988 [inline]
 path_mount+0x1986/0x2c30 fs/namespace.c:3318
 do_mount fs/namespace.c:3331 [inline]
 __do_sys_mount fs/namespace.c:3539 [inline]
 __se_sys_mount+0x308/0x3c0 fs/namespace.c:3516
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1338 [inline]
 free_pcp_prepare+0xc29/0xd20 mm/page_alloc.c:1389
 free_unref_page_prepare mm/page_alloc.c:3315 [inline]
 free_unref_page+0x7d/0x580 mm/page_alloc.c:3394
 lbmLogShutdown fs/jfs/jfs_logmgr.c:1872 [inline]
 lmLogShutdown+0x4ed/0x960 fs/jfs/jfs_logmgr.c:1692
 lmLogClose+0x2c2/0x560 fs/jfs/jfs_logmgr.c:1468
 jfs_umount+0x297/0x370 fs/jfs/jfs_umount.c:116
 jfs_put_super+0x86/0x190 fs/jfs/super.c:194
 generic_shutdown_super+0x12e/0x2b0 fs/super.c:465
 kill_block_super+0x79/0xd0 fs/super.c:1395
 deactivate_locked_super+0xa7/0xf0 fs/super.c:335
 cleanup_mnt+0x462/0x510 fs/namespace.c:1137
 task_work_run+0x146/0x1c0 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
 exit_to_user_mode_prepare+0x209/0x220 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x2e/0x70 kernel/entry/common.c:300
 do_syscall_64+0x53/0xd0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Memory state around the buggy address:
 ffff88808c6faf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88808c6faf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88808c6fb000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                   ^
 ffff88808c6fb080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88808c6fb100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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