syzbot

==================================================================
BUG: KASAN: use-after-free in dx_insert_block fs/ext4/namei.c:1358 [inline]
BUG: KASAN: use-after-free in do_split+0x1db1/0x2310 fs/ext4/namei.c:2042
Read of size 157024 at addr ffff88811099f028 by task syz-executor128/344

CPU: 1 PID: 344 Comm: syz-executor128 Not tainted 5.10.226-syzkaller-00184-g139a6bb26d9d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack_lvl+0x1e2/0x24b lib/dump_stack.c:118
 print_address_description+0x81/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:435 [inline]
 kasan_report+0x179/0x1c0 mm/kasan/report.c:452
 kasan_check_range+0x293/0x2a0 mm/kasan/generic.c:189
 memmove+0x2d/0x70 mm/kasan/shadow.c:54
 dx_insert_block fs/ext4/namei.c:1358 [inline]
 do_split+0x1db1/0x2310 fs/ext4/namei.c:2042
 make_indexed_dir+0xe3a/0x1500 fs/ext4/namei.c:2346
 ext4_add_entry+0xdcf/0x1280 fs/ext4/namei.c:2458
 __ext4_link+0x4e9/0x790 fs/ext4/namei.c:3645
 ext4_link+0x1f3/0x290 fs/ext4/namei.c:3686
 vfs_link+0x68f/0x890 fs/namei.c:4213
 do_linkat+0x471/0x8b0 fs/namei.c:4281
 __do_sys_link fs/namei.c:4310 [inline]
 __se_sys_link fs/namei.c:4308 [inline]
 __x64_sys_link+0x68/0x80 fs/namei.c:4308
 do_syscall_64+0x34/0x70
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7ff72ff915c9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 c1 1f 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ff72ff3e168 EFLAGS: 00000246 ORIG_RAX: 0000000000000056
RAX: ffffffffffffffda RBX: 00007ff7300194a8 RCX: 00007ff72ff915c9
RDX: 0000000000000000 RSI: 0000000020000bc0 RDI: 0000000020001240
RBP: 00007ff7300194a0 R08: 00007ff72ff3e6c0 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff7300194ac
R13: 000000000000000b R14: 00007ffcd04e1280 R15: 00007ffcd04e1368

The buggy address belongs to the page:
page:ffffea00044267c0 refcount:3 mapcount:1 mapping:ffff8881091a39d0 index:0x1 pfn:0x11099f
aops:def_blk_aops ino:0
flags: 0x400000000032201e(referenced|uptodate|dirty|lru|private|mappedtodisk|unevictable|mlocked)
raw: 400000000032201e ffff88810019a040 ffffea00043fab48 ffff8881091a39d0
raw: 0000000000000001 ffff88812084b540 0000000300000000 ffff888100144000
page dumped because: kasan: bad access detected
page->mem_cgroup:ffff888100144000
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 336, ts 32782368911, free_ts 32780705062
 set_page_owner include/linux/page_owner.h:35 [inline]
 post_alloc_hook mm/page_alloc.c:2456 [inline]
 prep_new_page+0x166/0x180 mm/page_alloc.c:2462
 get_page_from_freelist+0x2d8c/0x2f30 mm/page_alloc.c:4254
 __alloc_pages_nodemask+0x435/0xaf0 mm/page_alloc.c:5348
 __alloc_pages include/linux/gfp.h:544 [inline]
 __alloc_pages_node include/linux/gfp.h:557 [inline]
 alloc_pages_node include/linux/gfp.h:571 [inline]
 alloc_pages include/linux/gfp.h:590 [inline]
 __page_cache_alloc include/linux/pagemap.h:290 [inline]
 page_cache_ra_unbounded+0x363/0x890 mm/readahead.c:226
 do_page_cache_ra mm/readahead.c:277 [inline]
 force_page_cache_ra+0x373/0x3e0 mm/readahead.c:308
 page_cache_sync_ra+0x254/0x2c0 mm/readahead.c:582
 page_cache_sync_readahead include/linux/pagemap.h:837 [inline]
 generic_file_buffered_read+0x6da/0x2ad0 mm/filemap.c:2250
 generic_file_read_iter+0x107/0x6b0 mm/filemap.c:2568
 blkdev_read_iter+0x135/0x190 fs/block_dev.c:1956
 call_read_iter include/linux/fs.h:2017 [inline]
 new_sync_read fs/read_write.c:415 [inline]
 vfs_read+0x990/0xba0 fs/read_write.c:496
 ksys_read+0x199/0x2c0 fs/read_write.c:634
 __do_sys_read fs/read_write.c:644 [inline]
 __se_sys_read fs/read_write.c:642 [inline]
 __x64_sys_read+0x7b/0x90 fs/read_write.c:642
 do_syscall_64+0x34/0x70
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:28 [inline]
 free_pages_prepare mm/page_alloc.c:1349 [inline]
 free_pcp_prepare mm/page_alloc.c:1421 [inline]
 free_unref_page_prepare+0x2ae/0x2d0 mm/page_alloc.c:3336
 free_unref_page_list+0x122/0xb20 mm/page_alloc.c:3443
 release_pages+0xea0/0xef0 mm/swap.c:1103
 free_pages_and_swap_cache+0x8a/0xa0 mm/swap_state.c:356
 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:240 [inline]
 tlb_flush_mmu mm/mmu_gather.c:247 [inline]
 tlb_finish_mmu+0x177/0x320 mm/mmu_gather.c:326
 unmap_region+0x31c/0x370 mm/mmap.c:2810
 __do_munmap+0x699/0x8c0 mm/mmap.c:3041
 __vm_munmap mm/mmap.c:3064 [inline]
 __do_sys_munmap mm/mmap.c:3090 [inline]
 __se_sys_munmap+0x120/0x1a0 mm/mmap.c:3086
 __x64_sys_munmap+0x5b/0x70 mm/mmap.c:3086
 do_syscall_64+0x34/0x70
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Memory state around the buggy address:
 ffff88811099ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88811099ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8881109a0000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff8881109a0080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881109a0100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
EXT4-fs error (device loop0): ext4_dx_csum_set:529: inode #2: comm syz-executor128: dir seems corrupt?  Run e2fsck -D.