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BUG: KASAN: slab-use-after-free in ext4_ext_binsearch fs/ext4/extents.c:837 [inline]
BUG: KASAN: slab-use-after-free in ext4_find_extent+0xbc8/0xde0 fs/ext4/extents.c:953
Read of size 4 at addr ffff888015ffe000 by task syz-executor.3/31029

CPU: 1 PID: 31029 Comm: syz-executor.3 Not tainted 6.4.0-syzkaller-01312-gb19edac5992d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/27/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:351 [inline]
 print_report+0x163/0x540 mm/kasan/report.c:462
 kasan_report+0x176/0x1b0 mm/kasan/report.c:572
 ext4_ext_binsearch fs/ext4/extents.c:837 [inline]
 ext4_find_extent+0xbc8/0xde0 fs/ext4/extents.c:953
 finish_range+0x1e5/0x4c0 fs/ext4/migrate.c:37
 update_extent_range fs/ext4/migrate.c:82 [inline]
 update_ind_extent_range+0x2f7/0x520 fs/ext4/migrate.c:105
 ext4_ext_migrate+0xd7f/0x1430 fs/ext4/migrate.c:521
 __ext4_ioctl fs/ext4/ioctl.c:1396 [inline]
 ext4_ioctl+0x1c46/0x5610 fs/ext4/ioctl.c:1614
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:870 [inline]
 __se_sys_ioctl+0xf8/0x170 fs/ioctl.c:856
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f7cb1c8c389
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 f1 19 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f7cb2991168 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f7cb1dac050 RCX: 00007f7cb1c8c389
RDX: 0000000000000000 RSI: 0000000000006609 RDI: 0000000000000004
RBP: 00007f7cb1cd7493 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffe371735ff R14: 00007f7cb2991300 R15: 0000000000022000
 </TASK>

Allocated by task 4447:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4f/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:383
 kmalloc include/linux/slab.h:559 [inline]
 kzalloc include/linux/slab.h:680 [inline]
 smk_fetch+0x92/0x140 security/smack/smack_lsm.c:291
 smack_d_instantiate+0x6d9/0xb40 security/smack/smack_lsm.c:3475
 security_d_instantiate+0x9b/0xf0 security/security.c:3760
 d_splice_alias+0x6f/0x330 fs/dcache.c:3146
 __lookup_slow+0x282/0x3e0 fs/namei.c:1690
 lookup_slow+0x53/0x70 fs/namei.c:1707
 walk_component+0x2d0/0x400 fs/namei.c:1998
 lookup_last fs/namei.c:2455 [inline]
 path_lookupat+0x16f/0x450 fs/namei.c:2479
 filename_lookup+0x255/0x610 fs/namei.c:2508
 user_path_at_empty+0x44/0x180 fs/namei.c:2907
 do_readlinkat+0x118/0x3b0 fs/stat.c:477
 __do_sys_readlink fs/stat.c:510 [inline]
 __se_sys_readlink fs/stat.c:507 [inline]
 __x64_sys_readlink+0x7f/0x90 fs/stat.c:507
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 4447:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4f/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:521
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:162 [inline]
 slab_free_hook mm/slub.c:1781 [inline]
 slab_free_freelist_hook mm/slub.c:1807 [inline]
 slab_free mm/slub.c:3786 [inline]
 __kmem_cache_free+0x264/0x3c0 mm/slub.c:3799
 smk_fetch+0x109/0x140 security/smack/smack_lsm.c:303
 smack_d_instantiate+0x6d9/0xb40 security/smack/smack_lsm.c:3475
 security_d_instantiate+0x9b/0xf0 security/security.c:3760
 d_splice_alias+0x6f/0x330 fs/dcache.c:3146
 __lookup_slow+0x282/0x3e0 fs/namei.c:1690
 lookup_slow+0x53/0x70 fs/namei.c:1707
 walk_component+0x2d0/0x400 fs/namei.c:1998
 lookup_last fs/namei.c:2455 [inline]
 path_lookupat+0x16f/0x450 fs/namei.c:2479
 filename_lookup+0x255/0x610 fs/namei.c:2508
 user_path_at_empty+0x44/0x180 fs/namei.c:2907
 do_readlinkat+0x118/0x3b0 fs/stat.c:477
 __do_sys_readlink fs/stat.c:510 [inline]
 __se_sys_readlink fs/stat.c:507 [inline]
 __x64_sys_readlink+0x7f/0x90 fs/stat.c:507
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

The buggy address belongs to the object at ffff888015ffe000
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 0 bytes inside of
 freed 256-byte region [ffff888015ffe000, ffff888015ffe100)

The buggy address belongs to the physical page:
page:ffffea000057ff80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x15ffe
head:ffffea000057ff80 order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000010200 ffff888012441b40 ffffea0000aadf00 dead000000000002
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0x1d2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 5050, tgid 5050 (udevd), ts 1542612034028, free_ts 1538099944010
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1744
 prep_new_page mm/page_alloc.c:1751 [inline]
 get_page_from_freelist+0x320e/0x3390 mm/page_alloc.c:3523
 __alloc_pages+0x255/0x670 mm/page_alloc.c:4794
 alloc_slab_page+0x6a/0x160 mm/slub.c:1851
 allocate_slab mm/slub.c:1998 [inline]
 new_slab+0x84/0x2f0 mm/slub.c:2051
 ___slab_alloc+0xa85/0x10a0 mm/slub.c:3192
 __slab_alloc mm/slub.c:3291 [inline]
 __slab_alloc_node mm/slub.c:3344 [inline]
 slab_alloc_node mm/slub.c:3441 [inline]
 __kmem_cache_alloc_node+0x1b8/0x290 mm/slub.c:3490
 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1057
 kmalloc include/linux/slab.h:559 [inline]
 kzalloc include/linux/slab.h:680 [inline]
 smk_fetch+0x92/0x140 security/smack/smack_lsm.c:291
 smack_d_instantiate+0x8d7/0xb40 security/smack/smack_lsm.c:3518
 security_d_instantiate+0x9b/0xf0 security/security.c:3760
 d_instantiate+0x55/0x90 fs/dcache.c:2034
 shmem_mknod+0x17d/0x1c0 mm/shmem.c:3089
 lookup_open fs/namei.c:3492 [inline]
 open_last_lookups fs/namei.c:3560 [inline]
 path_openat+0x13e7/0x3180 fs/namei.c:3790
 do_filp_open+0x234/0x490 fs/namei.c:3820
 do_sys_openat2+0x13a/0x520 fs/open.c:1402
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1308 [inline]
 free_unref_page_prepare+0x903/0xa30 mm/page_alloc.c:2577
 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2672
 vfree+0x186/0x2e0 mm/vmalloc.c:2798
 delayed_vfree_work+0x56/0x80 mm/vmalloc.c:2719
 process_one_work+0x8a0/0x10e0 kernel/workqueue.c:2408
 worker_thread+0xa63/0x1210 kernel/workqueue.c:2555
 kthread+0x2b8/0x350 kernel/kthread.c:379
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

Memory state around the buggy address:
 ffff888015ffdf00: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc
 ffff888015ffdf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888015ffe000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff888015ffe080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888015ffe100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
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