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BUG: KASAN: use-after-free in diRead+0x975/0xbc0 fs/jfs/jfs_imap.c:329
Read of size 4 at addr ffff88805d048010 by task syz.0.316/9366

CPU: 0 UID: 0 PID: 9366 Comm: syz.0.316 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/06/2026
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+0x975/0xbc0 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+0xa5e/0x1b00 fs/namei.c:4536
 open_last_lookups fs/namei.c:4774 [inline]
 path_openat+0x711/0x2100 fs/namei.c:5013
 do_file_open+0x23e/0x4a0 fs/namei.c:5045
 do_sys_openat2+0x115/0x200 fs/open.c:1443
 do_sys_open fs/open.c:1449 [inline]
 __do_sys_openat fs/open.c:1465 [inline]
 __se_sys_openat fs/open.c:1460 [inline]
 __x64_sys_openat+0x138/0x170 fs/open.c:1460
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x16a/0x530 arch/x86/entry/syscall_64.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f86708a94d9
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:00007f866eaee028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f8670b25fa0 RCX: 00007f86708a94d9
RDX: 0000000000101042 RSI: 0000200000000500 RDI: ffffffffffffff9c
RBP: 00007f867093804e R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000015 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f8670b26038 R14: 00007f8670b25fa0 R15: 00007ffd04521e08
 </TASK>

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88805d048000 pfn:0x5d048
flags: 0x80000000000000(node=0|zone=1)
raw: 0080000000000000 ffffea0001605e08 ffffea0001699808 0000000000000000
raw: ffff88805d048000 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 9395, tgid 9365 (syz.0.316), ts 395496322438
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1860
 prep_new_page mm/page_alloc.c:1868 [inline]
 get_page_from_freelist+0x25d4/0x2650 mm/page_alloc.c:3950
 __alloc_frozen_pages_noprof+0x230/0x470 mm/page_alloc.c:5492
 alloc_pages_mpol+0xd4/0x280 mm/mempolicy.c:2513
 ___kmalloc_large_node+0x7b/0x170 mm/slub.c:5470
 __kmalloc_large_noprof+0x1a/0x90 mm/slub.c:5492
 _kmalloc_noprof include/linux/slab.h:988 [inline]
 _kzalloc_noprof include/linux/slab.h:1312 [inline]
 diMount+0x29/0xd80 fs/jfs/jfs_imap.c:105
 jfs_mount_rw+0x301/0x670 fs/jfs/jfs_mount.c:240
 jfs_reconfigure+0x5da/0x990 fs/jfs/super.c:409
 reconfigure_super+0x232/0x8f0 fs/super.c:1097
 do_remount fs/namespace.c:3538 [inline]
 path_mount+0xd51/0x1050 fs/namespace.c:4329
 do_mount fs/namespace.c:4350 [inline]
 __do_sys_mount fs/namespace.c:4563 [inline]
 __se_sys_mount+0x31d/0x420 fs/namespace.c:4540
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x16a/0x530 arch/x86/entry/syscall_64.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 9395 tgid 9365 ts 395496507537 stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 __free_pages_prepare mm/page_alloc.c:1402 [inline]
 __free_frozen_pages+0xfb6/0x1090 mm/page_alloc.c:2958
 diMount+0xbc2/0xd80 fs/jfs/jfs_imap.c:115
 jfs_mount_rw+0x301/0x670 fs/jfs/jfs_mount.c:240
 jfs_reconfigure+0x5da/0x990 fs/jfs/super.c:409
 reconfigure_super+0x232/0x8f0 fs/super.c:1097
 do_remount fs/namespace.c:3538 [inline]
 path_mount+0xd51/0x1050 fs/namespace.c:4329
 do_mount fs/namespace.c:4350 [inline]
 __do_sys_mount fs/namespace.c:4563 [inline]
 __se_sys_mount+0x31d/0x420 fs/namespace.c:4540
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x16a/0x530 arch/x86/entry/syscall_64.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff88805d047f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88805d047f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88805d048000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
                         ^
 ffff88805d048080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
 ffff88805d048100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
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