EXT4-fs (loop4): failed to convert unwritten extents to written extents -- potential data loss!  (inode 19, error -117)
==================================================================
BUG: KASAN: use-after-free in ext4_ext_binsearch fs/ext4/extents.c:826 [inline]
BUG: KASAN: use-after-free in ext4_find_extent+0xbeb/0xe20 fs/ext4/extents.c:945
Read of size 4 at addr ffff88812180da58 by task kworker/u4:6/408

CPU: 0 PID: 408 Comm: kworker/u4:6 Not tainted 5.10.237-syzkaller-1007464-g7e2543346ff7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: ext4-rsv-conversion ext4_end_io_rsv_work
Call Trace:
 __dump_stack+0x21/0x24 lib/dump_stack.c:77
 dump_stack_lvl+0x169/0x1d8 lib/dump_stack.c:118
 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:435 [inline]
 kasan_report+0xe2/0x130 mm/kasan/report.c:452
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308
 ext4_ext_binsearch fs/ext4/extents.c:826 [inline]
 ext4_find_extent+0xbeb/0xe20 fs/ext4/extents.c:945
 ext4_ext_map_blocks+0x1de/0x5d40 fs/ext4/extents.c:4159
 ext4_map_blocks+0x978/0x1bc0 fs/ext4/inode.c:674
 ext4_convert_unwritten_extents+0x21c/0x3f0 fs/ext4/extents.c:4860
 ext4_convert_unwritten_io_end_vec+0x103/0x180 fs/ext4/extents.c:4899
 ext4_end_io_end fs/ext4/page-io.c:189 [inline]
 ext4_do_flush_completed_IO fs/ext4/page-io.c:262 [inline]
 ext4_end_io_rsv_work+0x2b9/0x600 fs/ext4/page-io.c:276
 process_one_work+0x6e1/0xba0 kernel/workqueue.c:2301
 worker_thread+0xa6a/0x13b0 kernel/workqueue.c:2447
 kthread+0x346/0x3d0 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298

Allocated by task 368:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:430 [inline]
 __kasan_slab_alloc+0xbd/0xf0 mm/kasan/common.c:463
 kasan_slab_alloc include/linux/kasan.h:244 [inline]
 slab_post_alloc_hook+0x5d/0x2f0 mm/slab.h:583
 slab_alloc_node mm/slub.c:2947 [inline]
 slab_alloc mm/slub.c:2955 [inline]
 kmem_cache_alloc+0x165/0x2e0 mm/slub.c:2960
 proc_alloc_inode+0x1d/0xb0 fs/proc/inode.c:69
 alloc_inode fs/inode.c:233 [inline]
 new_inode_pseudo+0x62/0x210 fs/inode.c:968
 new_inode+0x28/0x1e0 fs/inode.c:997
 proc_pid_make_inode+0x27/0x1d0 fs/proc/base.c:1953
 proc_pident_instantiate+0x69/0x2b0 fs/proc/base.c:2694
 proc_pident_lookup+0x1c0/0x270 fs/proc/base.c:2730
 proc_tgid_base_lookup+0x2b/0x30 fs/proc/base.c:3394
 lookup_open fs/namei.c:3226 [inline]
 open_last_lookups fs/namei.c:3317 [inline]
 path_openat+0x1127/0x3160 fs/namei.c:3506
 do_filp_open+0x1b3/0x3e0 fs/namei.c:3536
 do_sys_openat2+0x14c/0x6d0 fs/open.c:1217
 do_sys_open fs/open.c:1233 [inline]
 __do_sys_openat fs/open.c:1249 [inline]
 __se_sys_openat fs/open.c:1244 [inline]
 __x64_sys_openat+0x136/0x160 fs/open.c:1244
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Freed by task 49:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4a/0x70 mm/kasan/common.c:45
 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370
 ____kasan_slab_free+0x125/0x160 mm/kasan/common.c:362
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:370
 kasan_slab_free include/linux/kasan.h:220 [inline]
 slab_free_hook mm/slub.c:1595 [inline]
 slab_free_freelist_hook+0xc5/0x190 mm/slub.c:1621
 slab_free mm/slub.c:3203 [inline]
 kmem_cache_free+0x100/0x2d0 mm/slub.c:3219
 proc_free_inode+0x20/0x30 fs/proc/inode.c:85
 i_callback+0x4c/0x70 fs/inode.c:222
 rcu_do_batch+0x4df/0xa80 kernel/rcu/tree.c:2494
 rcu_core+0x55f/0xd60 kernel/rcu/tree.c:2735
 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2748
 __do_softirq+0x255/0x563 kernel/softirq.c:309

Last potentially related work creation:
 kasan_save_stack+0x3a/0x60 mm/kasan/common.c:38
 __kasan_record_aux_stack+0xd2/0x100 mm/kasan/generic.c:348
 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358
 __call_rcu kernel/rcu/tree.c:2976 [inline]
 call_rcu+0x105/0x1040 kernel/rcu/tree.c:3050
 destroy_inode fs/inode.c:288 [inline]
 evict+0x857/0x910 fs/inode.c:629
 iput_final fs/inode.c:1736 [inline]
 iput+0x638/0x7c0 fs/inode.c:1762
 dentry_unlink_inode+0x2cf/0x380 fs/dcache.c:378
 __dentry_kill+0x44f/0x650 fs/dcache.c:583
 shrink_dentry_list+0x38e/0x500 fs/dcache.c:1146
 shrink_dcache_parent+0xa3/0x250 fs/dcache.c:-1
 d_invalidate+0x113/0x2d0 fs/dcache.c:1682
 proc_invalidate_siblings_dcache+0x298/0x3c0 fs/proc/inode.c:150
 proc_flush_pid+0x1d/0x20 fs/proc/base.c:3427
 release_task+0x10b9/0x1200 kernel/exit.c:270
 wait_task_zombie kernel/exit.c:1170 [inline]
 wait_consider_task+0x193c/0x28b0 kernel/exit.c:1397
 do_wait_thread kernel/exit.c:1460 [inline]
 do_wait+0x244/0x6c0 kernel/exit.c:1531
 kernel_wait4+0x1a5/0x260 kernel/exit.c:1693
 __do_sys_wait4 kernel/exit.c:1721 [inline]
 __se_sys_wait4 kernel/exit.c:1717 [inline]
 __x64_sys_wait4+0x130/0x1e0 kernel/exit.c:1717
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

The buggy address belongs to the object at ffff88812180d8b8
 which belongs to the cache proc_inode_cache of size 776
The buggy address is located 416 bytes inside of
 776-byte region [ffff88812180d8b8, ffff88812180dbc0)
The buggy address belongs to the page:
page:ffffea0004860300 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12180c
head:ffffea0004860300 order:2 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head)
raw: 4000000000010200 dead000000000100 dead000000000122 ffff88810018b680
raw: 0000000000000000 0000000000120012 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Reclaimable, gfp_mask 0x1d20d0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 332, ts 45743366631, free_ts 0
 set_page_owner include/linux/page_owner.h:35 [inline]
 post_alloc_hook mm/page_alloc.c:2456 [inline]
 prep_new_page+0x179/0x180 mm/page_alloc.c:2462
 get_page_from_freelist+0x2235/0x23d0 mm/page_alloc.c:4254
 __alloc_pages_nodemask+0x268/0x5f0 mm/page_alloc.c:5349
 alloc_slab_page mm/slub.c:-1 [inline]
 allocate_slab mm/slub.c:1808 [inline]
 new_slab+0x84/0x3f0 mm/slub.c:1869
 new_slab_objects mm/slub.c:2627 [inline]
 ___slab_alloc+0x2a6/0x450 mm/slub.c:2791
 __slab_alloc+0x63/0xa0 mm/slub.c:2831
 slab_alloc_node mm/slub.c:2913 [inline]
 slab_alloc mm/slub.c:2955 [inline]
 kmem_cache_alloc+0x1af/0x2e0 mm/slub.c:2960
 proc_alloc_inode+0x1d/0xb0 fs/proc/inode.c:69
 alloc_inode fs/inode.c:233 [inline]
 new_inode_pseudo+0x62/0x210 fs/inode.c:968
 new_inode+0x28/0x1e0 fs/inode.c:997
 proc_sys_make_inode+0x4f/0x570 fs/proc/proc_sysctl.c:440
 proc_sys_lookup+0x4df/0x610 fs/proc/proc_sysctl.c:527
 lookup_open fs/namei.c:3226 [inline]
 open_last_lookups fs/namei.c:3317 [inline]
 path_openat+0x1127/0x3160 fs/namei.c:3506
 do_filp_open+0x1b3/0x3e0 fs/namei.c:3536
 do_sys_openat2+0x14c/0x6d0 fs/open.c:1217
 do_sys_open fs/open.c:1233 [inline]
 __do_sys_openat fs/open.c:1249 [inline]
 __se_sys_openat fs/open.c:1244 [inline]
 __x64_sys_openat+0x136/0x160 fs/open.c:1244
page_owner free stack trace missing

Memory state around the buggy address:
 ffff88812180d900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88812180d980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88812180da00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                    ^
 ffff88812180da80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88812180db00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
EXT4-fs error (device loop4): ext4_map_blocks:740: inode #19: block 2231946762: comm kworker/u4:6: lblock 10 mapped to illegal pblock 2231946762 (length 1)
EXT4-fs warning (device loop4): ext4_convert_unwritten_extents:4867: inode #19: block 10: len 1: ext4_ext_map_blocks returned -117
EXT4-fs error (device loop4): __ext4_get_inode_loc:4438: comm kworker/u4:6: Invalid inode table block 34360905424 in block_group 0
EXT4-fs error (device loop4) in ext4_reserve_inode_write:5932: Corrupt filesystem
EXT4-fs error (device loop4): ext4_convert_unwritten_extents:4868: inode #19: comm kworker/u4:6: mark_inode_dirty error
EXT4-fs (loop4): failed to convert unwritten extents to written extents -- potential data loss!  (inode 19, error -117)
EXT4-fs error (device loop4): __ext4_get_inode_loc:4438: comm kworker/u4:6: Invalid inode table block 34360905424 in block_group 0
EXT4-fs error (device loop5): __ext4_get_inode_loc:4438: comm kworker/u4:6: Invalid inode table block 34360905424 in block_group 0
EXT4-fs error (device loop2): __ext4_get_inode_loc:4438: comm kworker/u4:6: Invalid inode table block 34360905424 in block_group 0