Kernel bug: KASAN: slab-out-of-bounds Read in dtReadFirst
Subsystem: jfs
Status: open

Crash report:
loop0: detected capacity change from 0 to 32768
==================================================================
BUG: KASAN: slab-out-of-b[  121.657564][ T6065] BUG: KASAN: slab-out-of-bounds in addressPXD fs/jfs/jfs_types.h:80 [inline]
BUG: KASAN: slab-out-of-b[  121.657564][ T6065] BUG: KASAN: slab-out-of-bounds in dtReadFirst+0x502/0x930 fs/jfs/jfs_dtree.c:3120
Read of size 4 at addr ffff8880579f2f60 by task syz.0.17/6065

CPU: 1 UID: 0 PID: 6065 Comm: syz.0.17 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
 <TASK>
 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
 addressPXD fs/jfs/jfs_types.h:80 [inline]
 dtReadFirst+0x502/0x930 fs/jfs/jfs_dtree.c:3120
 jfs_readdir+0x70c/0x3ae0 fs/jfs/jfs_dtree.c:2832
 wrap_directory_iterator+0x99/0xe0 fs/readdir.c:65
 iterate_dir+0x3a5/0x580 fs/readdir.c:108
 __do_sys_getdents64 fs/readdir.c:410 [inline]
 __se_sys_getdents64+0xe4/0x260 fs/readdir.c:396
 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
RIP: 0033:0x7fa5ebbbefc9
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:00007ffcda5c8d08 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007fa5ebe15fa0 RCX: 00007fa5ebbbefc9
RDX: 0000000000000099 RSI: 0000200000000400 RDI: 0000000000000005
RBP: 00007fa5ebc41f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fa5ebe15fa0 R14: 00007fa5ebe15fa0 R15: 0000000000000003
 </TASK>

The buggy address belongs to the object at ffff8880579f2700
 which belongs to the cache jfs_ip of size 2368
The buggy address is located 2144 bytes inside of
 allocated 2368-byte region [ffff8880579f2700, ffff8880579f3040)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x579f0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
memcg:ffff888048eb4c01
flags: 0x80000000000040(head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000040 ffff88801eb4ba00 dead000000000122 0000000000000000
raw: 0000000000000000 00000000800d000d 00000000f5000000 ffff888048eb4c01
head: 0080000000000040 ffff88801eb4ba00 dead000000000122 0000000000000000
head: 0000000000000000 00000000800d000d 00000000f5000000 ffff888048eb4c01
head: 0080000000000003 ffffea00015e7c01 00000000ffffffff 00000000ffffffff
head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Reclaimable, gfp_mask 0xd2050(__GFP_RECLAIMABLE|__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6065, tgid 6065 (syz.0.17), ts 121611315597, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1850
 prep_new_page mm/page_alloc.c:1858 [inline]
 get_page_from_freelist+0x28c0/0x2960 mm/page_alloc.c:3884
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5183
 alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2416
 alloc_slab_page mm/slub.c:3046 [inline]
 allocate_slab+0x96/0x3a0 mm/slub.c:3219
 new_slab mm/slub.c:3273 [inline]
 ___slab_alloc+0xb12/0x13f0 mm/slub.c:4643
 __slab_alloc+0xc6/0x1f0 mm/slub.c:4762
 __slab_alloc_node mm/slub.c:4838 [inline]
 slab_alloc_node mm/slub.c:5260 [inline]
 kmem_cache_alloc_lru_noprof+0xf0/0x6b0 mm/slub.c:5291
 jfs_alloc_inode+0x28/0x70 fs/jfs/super.c:105
 alloc_inode+0x6a/0x1b0 fs/inode.c:346
 new_inode+0x22/0x170 fs/inode.c:1145
 diReadSpecial+0x52/0x710 fs/jfs/jfs_imap.c:426
 jfs_mount+0x174/0x870 fs/jfs/jfs_mount.c:108
 jfs_fill_super+0x6bc/0xd80 fs/jfs/super.c:523
 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1691
 vfs_get_tree+0x92/0x2b0 fs/super.c:1751
page_owner free stack trace missing

Memory state around the buggy address:
 ffff8880579f2e00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880579f2e80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880579f2f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
                                                       ^
 ffff8880579f2f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880579f3000: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================