hpfs: code page support is disabled
hpfs: filesystem error: map_dirent: not a directory
hpfs: hpfs_map_4sectors(): unaligned read
hpfs: filesystem error: unable to find root dir
==================================================================
BUG: KASAN: slab-use-after-free in hpfs_bplus_lookup+0x4dc/0x860 fs/hpfs/anode.c:38
Read of size 4 at addr ffff88803ccd0004 by task syz.0.29/6093

CPU: 1 UID: 0 PID: 6093 Comm: syz.0.29 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 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
 hpfs_bplus_lookup+0x4dc/0x860 fs/hpfs/anode.c:38
 hpfs_bmap+0x22a/0x4d0 fs/hpfs/file.c:54
 hpfs_get_block+0xa8/0x6e0 fs/hpfs/file.c:87
 do_mpage_readpage+0x822/0x1990 fs/mpage.c:222
 mpage_readahead+0x3b0/0x790 fs/mpage.c:371
 read_pages+0x17a/0x580 mm/readahead.c:163
 page_cache_ra_unbounded+0x68b/0x8c0 mm/readahead.c:302
 filemap_get_pages+0x446/0x1ee0 mm/filemap.c:2690
 filemap_read+0x3f9/0x11a0 mm/filemap.c:2800
 __kernel_read+0x4d8/0x970 fs/read_write.c:530
 integrity_kernel_read+0x89/0xd0 security/integrity/iint.c:28
 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:480 [inline]
 ima_calc_file_shash security/integrity/ima/ima_crypto.c:511 [inline]
 ima_calc_file_hash+0x86a/0x1700 security/integrity/ima/ima_crypto.c:568
 ima_collect_measurement+0x42e/0x900 security/integrity/ima/ima_api.c:293
 process_measurement+0x112a/0x1a80 security/integrity/ima/ima_main.c:406
 ima_file_check+0xd9/0x130 security/integrity/ima/ima_main.c:663
 security_file_post_open+0xbb/0x290 security/security.c:2652
 do_open fs/namei.c:4639 [inline]
 path_openat+0x3472/0x3df0 fs/namei.c:4796
 do_filp_open+0x1fa/0x410 fs/namei.c:4823
 do_sys_openat2+0x121/0x200 fs/open.c:1430
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_openat fs/open.c:1452 [inline]
 __se_sys_openat fs/open.c:1447 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1447
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f669adbf749
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffd3c9885c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f669b015fa0 RCX: 00007f669adbf749
RDX: 0000000000000000 RSI: 0000200000004280 RDI: ffffffffffffff9c
RBP: 00007f669ae43f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f669b015fa0 R14: 00007f669b015fa0 R15: 0000000000000004
 </TASK>

Allocated by task 5160:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __do_kmalloc_node mm/slub.c:5657 [inline]
 __kmalloc_node_track_caller_noprof+0x3a2/0x810 mm/slub.c:5764
 kmalloc_reserve+0x136/0x290 net/core/skbuff.c:608
 __alloc_skb+0x204/0x3a0 net/core/skbuff.c:690
 alloc_skb include/linux/skbuff.h:1383 [inline]
 alloc_skb_with_frags+0xca/0x890 net/core/skbuff.c:6714
 sock_alloc_send_pskb+0x859/0x990 net/core/sock.c:2995
 unix_dgram_sendmsg+0x454/0x1840 net/unix/af_unix.c:2130
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:742
 __sys_sendto+0x3c7/0x520 net/socket.c:2206
 __do_sys_sendto net/socket.c:2213 [inline]
 __se_sys_sendto net/socket.c:2209 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2209
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5153:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2540 [inline]
 slab_free mm/slub.c:6670 [inline]
 kfree+0x1bd/0x900 mm/slub.c:6878
 skb_release_data+0x62d/0x7c0 net/core/skbuff.c:1107
 skb_release_all net/core/skbuff.c:1182 [inline]
 __kfree_skb net/core/skbuff.c:1196 [inline]
 consume_skb+0x9e/0xf0 net/core/skbuff.c:1428
 __unix_dgram_recvmsg+0x9f9/0xd60 net/unix/af_unix.c:2658
 sock_recvmsg_nosec net/socket.c:1078 [inline]
 sock_recvmsg+0x22c/0x270 net/socket.c:1100
 sock_read_iter+0x23a/0x2f0 net/socket.c:1170
 new_sync_read fs/read_write.c:491 [inline]
 vfs_read+0x563/0xa30 fs/read_write.c:572
 ksys_read+0x14b/0x260 fs/read_write.c:715
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88803ccd0000
 which belongs to the cache kmalloc-cg-512 of size 512
The buggy address is located 4 bytes inside of
 freed 512-byte region [ffff88803ccd0000, ffff88803ccd0200)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x3ccd0
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff8880570c1101
flags: 0x80000000000040(head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000040 ffff88813ff30140 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000100010 00000000f5000000 ffff8880570c1101
head: 0080000000000040 ffff88813ff30140 dead000000000122 0000000000000000
head: 0000000000000000 0000000000100010 00000000f5000000 ffff8880570c1101
head: 0080000000000002 ffffea0000f33401 00000000ffffffff 00000000ffffffff
head: ffff88803ccd1b40 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5160, tgid 5160 (klogd), ts 125223722131, free_ts 106814025219
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x234/0x290 mm/page_alloc.c:1857
 prep_new_page mm/page_alloc.c:1865 [inline]
 get_page_from_freelist+0x28c0/0x2960 mm/page_alloc.c:3915
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210
 alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2486
 alloc_slab_page mm/slub.c:3075 [inline]
 allocate_slab+0x86/0x3b0 mm/slub.c:3248
 new_slab mm/slub.c:3302 [inline]
 ___slab_alloc+0xb10/0x13e0 mm/slub.c:4656
 __slab_alloc+0xc6/0x1f0 mm/slub.c:4779
 __slab_alloc_node mm/slub.c:4855 [inline]
 slab_alloc_node mm/slub.c:5251 [inline]
 __do_kmalloc_node mm/slub.c:5656 [inline]
 __kmalloc_node_track_caller_noprof+0x2bf/0x810 mm/slub.c:5764
 kmalloc_reserve+0x136/0x290 net/core/skbuff.c:608
 __alloc_skb+0x204/0x3a0 net/core/skbuff.c:690
 alloc_skb include/linux/skbuff.h:1383 [inline]
 alloc_skb_with_frags+0xca/0x890 net/core/skbuff.c:6714
 sock_alloc_send_pskb+0x859/0x990 net/core/sock.c:2995
 unix_dgram_sendmsg+0x454/0x1840 net/unix/af_unix.c:2130
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg+0x21c/0x270 net/socket.c:742
 __sys_sendto+0x3c7/0x520 net/socket.c:2206
 __do_sys_sendto net/socket.c:2213 [inline]
 __se_sys_sendto net/socket.c:2209 [inline]
 __x64_sys_sendto+0xde/0x100 net/socket.c:2209
page last free pid 28 tgid 28 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1406 [inline]
 __free_frozen_pages+0xfe1/0x1170 mm/page_alloc.c:2943
 rcu_do_batch kernel/rcu/tree.c:2605 [inline]
 rcu_core kernel/rcu/tree.c:2857 [inline]
 rcu_cpu_kthread+0xba5/0x1af0 kernel/rcu/tree.c:2945
 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x510/0xa50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

Memory state around the buggy address:
 ffff88803cccff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88803cccff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88803ccd0000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff88803ccd0080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88803ccd0100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================