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BUG: KASAN: slab-use-after-free in jfs_readdir+0x1223/0x3c10 fs/jfs/jfs_dtree.c:2881
Read of size 8 at addr ffff8880002aa9e0 by task syz.0.0/5317

CPU: 0 UID: 0 PID: 5317 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xba/0x230 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 jfs_readdir+0x1223/0x3c10 fs/jfs/jfs_dtree.c:2881
 wrap_directory_iterator+0x96/0xe0 fs/readdir.c:65
 iterate_dir+0x399/0x570 fs/readdir.c:108
 __do_sys_getdents64 fs/readdir.c:412 [inline]
 __se_sys_getdents64+0xf1/0x280 fs/readdir.c:397
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f52e939c629
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:00007f52ea286028 EFLAGS: 00000246 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 00007f52e9616090 RCX: 00007f52e939c629
RDX: 0000000000001000 RSI: 0000200000011840 RDI: 0000000000000008
RBP: 00007f52e9432b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f52e9616128 R14: 00007f52e9616090 R15: 00007fff636bcfd8
 </TASK>

Allocated by task 5317:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 unpoison_slab_object mm/kasan/common.c:340 [inline]
 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:366
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4501 [inline]
 slab_alloc_node mm/slub.c:4830 [inline]
 kmem_cache_alloc_noprof+0x2bc/0x650 mm/slub.c:4837
 mempool_alloc_noprof+0x1ce/0x300 mm/mempool.c:566
 alloc_metapage fs/jfs/jfs_metapage.c:264 [inline]
 __get_metapage+0x50c/0xde0 fs/jfs/jfs_metapage.c:760
 dtSplitRoot+0x202/0x16c0 fs/jfs/jfs_dtree.c:1910
 dtSplitUp fs/jfs/jfs_dtree.c:993 [inline]
 dtInsert+0xf19/0x5f10 fs/jfs/jfs_dtree.c:871
 jfs_create+0x75b/0xb10 fs/jfs/namei.c:138
 lookup_open fs/namei.c:4483 [inline]
 open_last_lookups fs/namei.c:4583 [inline]
 path_openat+0x1395/0x3860 fs/namei.c:4827
 do_file_open+0x23e/0x4a0 fs/namei.c:4859
 do_sys_openat2+0x113/0x200 fs/open.c:1366
 do_sys_open fs/open.c:1372 [inline]
 __do_sys_creat fs/open.c:1450 [inline]
 __se_sys_creat fs/open.c:1444 [inline]
 __x64_sys_creat+0x8f/0xc0 fs/open.c:1444
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5317:
 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:2687 [inline]
 slab_free mm/slub.c:6124 [inline]
 kmem_cache_free+0x187/0x630 mm/slub.c:6254
 mempool_free+0xec/0x130 mm/mempool.c:711
 free_metapage fs/jfs/jfs_metapage.c:279 [inline]
 drop_metapage fs/jfs/jfs_metapage.c:316 [inline]
 release_metapage+0x859/0xac0 fs/jfs/jfs_metapage.c:892
 dtReadNext fs/jfs/jfs_dtree.c:3202 [inline]
 jfs_readdir+0xf4c/0x3c10 fs/jfs/jfs_dtree.c:2874
 wrap_directory_iterator+0x96/0xe0 fs/readdir.c:65
 iterate_dir+0x399/0x570 fs/readdir.c:108
 __do_sys_getdents64 fs/readdir.c:412 [inline]
 __se_sys_getdents64+0xf1/0x280 fs/readdir.c:397
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff8880002aa9b0
 which belongs to the cache jfs_mp of size 184
The buggy address is located 48 bytes inside of
 freed 184-byte region [ffff8880002aa9b0, ffff8880002aaa68)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2aa
flags: 0x7ff00000000000(node=0|zone=0|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 007ff00000000000 ffff888031abcb40 dead000000000122 0000000000000000
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 8311246429, free_ts 0
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x231/0x280 mm/page_alloc.c:1889
 prep_new_page mm/page_alloc.c:1897 [inline]
 get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3962
 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250
 alloc_slab_page mm/slub.c:3255 [inline]
 allocate_slab+0x77/0x660 mm/slub.c:3444
 new_slab mm/slub.c:3502 [inline]
 refill_objects+0x331/0x3c0 mm/slub.c:7134
 refill_sheaf+0x29/0x50 mm/slub.c:2804
 alloc_full_sheaf mm/slub.c:2825 [inline]
 __pcs_replace_empty_main+0x3ef/0x620 mm/slub.c:4588
 alloc_from_pcs mm/slub.c:4681 [inline]
 slab_alloc_node mm/slub.c:4815 [inline]
 kmem_cache_alloc_noprof+0x37d/0x650 mm/slub.c:4837
 mempool_init_node+0x1ea/0x4d0 mm/mempool.c:259
 mempool_create_node_noprof+0xb8/0x150 mm/mempool.c:323
 metapage_init+0xed/0x150 fs/jfs/jfs_metapage.c:292
 init_jfs_fs+0xfd/0x4e0 fs/jfs/super.c:968
 do_one_initcall+0x250/0x8d0 init/main.c:1382
 do_initcall_level+0x104/0x190 init/main.c:1444
 do_initcalls+0x59/0xa0 init/main.c:1460
 kernel_init_freeable+0x2a6/0x3e0 init/main.c:1692
page_owner free stack trace missing

Memory state around the buggy address:
 ffff8880002aa880: fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 00
 ffff8880002aa900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 fc fc
>ffff8880002aa980: fc fc fc fc fc fc fa fb fb fb fb fb fb fb fb fb
                                                       ^
 ffff8880002aaa00: fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc
 ffff8880002aaa80: fc fc fc fc fc 00 00 00 00 00 00 00 00 00 00 00
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