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BUG: KASAN: use-after-free in diRead+0x94f/0xb90 fs/jfs/jfs_imap.c:329
Read of size 4 at addr ffff888066780010 by task syz.2.557/9224

CPU: 1 UID: 0 PID: 9224 Comm: syz.2.557 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 diRead+0x94f/0xb90 fs/jfs/jfs_imap.c:329
 jfs_iget+0x89/0x470 fs/jfs/inode.c:35
 jfs_lookup+0x220/0x420 fs/jfs/namei.c:1472
 lookup_open fs/namei.c:4484 [inline]
 open_last_lookups fs/namei.c:4611 [inline]
 path_openat+0x11cb/0x38a0 fs/namei.c:4855
 do_file_open+0x23e/0x4a0 fs/namei.c:4887
 do_sys_openat2+0x113/0x200 fs/open.c:1364
 do_sys_open fs/open.c:1370 [inline]
 __do_sys_openat fs/open.c:1386 [inline]
 __se_sys_openat fs/open.c:1381 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1381
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fea06e9ce59
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fea050ac028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fea07116180 RCX: 00007fea06e9ce59
RDX: 0000000000183341 RSI: 0000200000000080 RDI: ffffffffffffff9c
RBP: 00007fea06f32d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000045 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fea07116218 R14: 00007fea07116180 R15: 00007fff693b7ca8
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888066780000 pfn:0x66780
flags: 0x80000000000000(node=0|zone=1)
raw: 0080000000000000 ffffea0001987008 ffff8880b8942d30 0000000000000000
raw: ffff888066780000 0000000000000000 00000000ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as freed
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x40dc0(GFP_KERNEL|__GFP_ZERO|__GFP_COMP), pid 9213, tgid 9212 (syz.2.557), ts 393173580825, free_ts 393188409012
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x22d/0x280 mm/page_alloc.c:1853
 prep_new_page mm/page_alloc.c:1861 [inline]
 get_page_from_freelist+0x28b2/0x2930 mm/page_alloc.c:3941
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5221
 alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2490
 ___kmalloc_large_node+0x4e/0x120 mm/slub.c:5237
 __kmalloc_large_noprof+0x1a/0x90 mm/slub.c:5258
 kmalloc_noprof include/linux/slab.h:947 [inline]
 kzalloc_noprof include/linux/slab.h:1188 [inline]
 diMount+0x29/0xd80 fs/jfs/jfs_imap.c:105
 jfs_mount_rw+0x34c/0x670 fs/jfs/jfs_mount.c:240
 jfs_reconfigure+0x5f9/0xa00 fs/jfs/super.c:409
 reconfigure_super+0x227/0x8a0 fs/super.c:1080
 do_remount fs/namespace.c:3400 [inline]
 path_mount+0xdc5/0x10e0 fs/namespace.c:4146
 do_mount fs/namespace.c:4167 [inline]
 __do_sys_mount fs/namespace.c:4383 [inline]
 __se_sys_mount+0x31d/0x420 fs/namespace.c:4360
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 9213 tgid 9212 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1397 [inline]
 __free_frozen_pages+0xfe5/0x10d0 mm/page_alloc.c:2938
 diMount+0xbc2/0xd80 fs/jfs/jfs_imap.c:115
 jfs_mount_rw+0x34c/0x670 fs/jfs/jfs_mount.c:240
 jfs_reconfigure+0x5f9/0xa00 fs/jfs/super.c:409
 reconfigure_super+0x227/0x8a0 fs/super.c:1080
 do_remount fs/namespace.c:3400 [inline]
 path_mount+0xdc5/0x10e0 fs/namespace.c:4146
 do_mount fs/namespace.c:4167 [inline]
 __do_sys_mount fs/namespace.c:4383 [inline]
 __se_sys_mount+0x31d/0x420 fs/namespace.c:4360
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88806677ff00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88806677ff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888066780000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                         ^
 ffff888066780080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff888066780100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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