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BUG: KASAN: slab-out-of-bounds in ext4_get_inode_usage+0x3a1/0x520 fs/ext4/xattr.c:817
Read of size 4 at addr ffff8881132910ec by task syz.0.8467/25609

CPU: 0 PID: 25609 Comm: syz.0.8467 Tainted: G        W         syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 __dump_stack+0x21/0x24 lib/dump_stack.c:77
 dump_stack_lvl+0x1a7/0x208 lib/dump_stack.c:118
 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:435 [inline]
 kasan_report+0xe2/0x130 mm/kasan/report.c:452
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308
 ext4_get_inode_usage+0x3a1/0x520 fs/ext4/xattr.c:817
 __dquot_transfer+0x192/0x20d0 fs/quota/dquot.c:2017
 dquot_transfer+0x2f1/0x460 fs/quota/dquot.c:2169
 ext4_setattr+0x715/0x1950 fs/ext4/inode.c:5577
 notify_change+0xab3/0xe40 fs/attr.c:410
 chown_common+0x335/0x500 fs/open.c:675
 vfs_fchown fs/open.c:742 [inline]
 ksys_fchown+0xef/0x160 fs/open.c:753
 __do_sys_fchown fs/open.c:761 [inline]
 __se_sys_fchown fs/open.c:759 [inline]
 __x64_sys_fchown+0x7a/0x90 fs/open.c:759
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f01740e0e59
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:00007f0172b3b028 EFLAGS: 00000246 ORIG_RAX: 000000000000005d
RAX: ffffffffffffffda RBX: 00007f0174359fa0 RCX: 00007f01740e0e59
RDX: 000000000000ee01 RSI: 0000000000000000 RDI: 0000000000000005
RBP: 00007f0174176d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f017435a038 R14: 00007f0174359fa0 R15: 00007ffdc66776f8

Allocated by task 25169:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:430 [inline]
 ____kasan_kmalloc mm/kasan/common.c:509 [inline]
 __kasan_kmalloc+0xda/0x110 mm/kasan/common.c:518
 kasan_kmalloc include/linux/kasan.h:254 [inline]
 __kmalloc+0x1a4/0x330 mm/slub.c:4038
 kmalloc include/linux/slab.h:560 [inline]
 inotify_handle_inode_event+0x172/0x520 fs/notify/inotify/inotify_fsnotify.c:95
 inotify_ignored_and_remove_idr+0x29/0x70 fs/notify/inotify/inotify_user.c:491
 inotify_freeing_mark+0x1d/0x30 fs/notify/inotify/inotify_fsnotify.c:139
 fsnotify_free_mark fs/notify/mark.c:453 [inline]
 fsnotify_destroy_mark+0x12f/0x190 fs/notify/mark.c:462
 __do_sys_inotify_rm_watch fs/notify/inotify/inotify_user.c:801 [inline]
 __se_sys_inotify_rm_watch+0xcb/0x140 fs/notify/inotify/inotify_user.c:778
 __x64_sys_inotify_rm_watch+0x5b/0x70 fs/notify/inotify/inotify_user.c:778
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Last potentially related work creation:
 kasan_save_stack+0x3a/0x60 mm/kasan/common.c:38
 __kasan_record_aux_stack+0xd2/0x100 mm/kasan/generic.c:348
 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358
 kvfree_call_rcu+0x11c/0x650 kernel/rcu/tree.c:3539
 fib_notifier_ops_unregister+0xe7/0x100 net/core/fib_notifier.c:167
 fib6_notifier_exit+0x3b/0x40 net/ipv6/fib6_notifier.c:63
 fib6_net_exit+0x2e7/0x300 net/ipv6/ip6_fib.c:2436
 ops_exit_list net/core/net_namespace.c:185 [inline]
 cleanup_net+0x58e/0xb80 net/core/net_namespace.c:609
 process_one_work+0x6e1/0xba0 kernel/workqueue.c:2301
 worker_thread+0xa6a/0x13c0 kernel/workqueue.c:2447
 kthread+0x346/0x3d0 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298

The buggy address belongs to the object at ffff888113291080
 which belongs to the cache kmalloc-64 of size 64
The buggy address is located 44 bytes to the right of
 64-byte region [ffff888113291080, ffff8881132910c0)
The buggy address belongs to the page:
page:ffffea00044ca440 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888113291e80 pfn:0x113291
flags: 0x4000000000000200(slab)
raw: 4000000000000200 ffffea0004630a48 ffff888100040e10 ffff888100043800
raw: ffff888113291e80 0000000000200008 00000001ffffffff 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 94, ts 6998583411, free_ts 6996902287
 set_page_owner include/linux/page_owner.h:35 [inline]
 post_alloc_hook mm/page_alloc.c:2456 [inline]
 prep_new_page+0x179/0x180 mm/page_alloc.c:2462
 get_page_from_freelist+0x223b/0x23d0 mm/page_alloc.c:4254
 __alloc_pages_nodemask+0x290/0x620 mm/page_alloc.c:5384
 alloc_slab_page mm/slub.c:-1 [inline]
 allocate_slab mm/slub.c:1813 [inline]
 new_slab+0x84/0x3f0 mm/slub.c:1874
 new_slab_objects mm/slub.c:2632 [inline]
 ___slab_alloc+0x2a6/0x450 mm/slub.c:2796
 __slab_alloc+0x63/0xa0 mm/slub.c:2836
 slab_alloc_node mm/slub.c:2918 [inline]
 slab_alloc mm/slub.c:2960 [inline]
 kmem_cache_alloc_trace+0x1b0/0x2e0 mm/slub.c:2977
 kmalloc include/linux/slab.h:555 [inline]
 kernfs_get_open_node fs/kernfs/file.c:552 [inline]
 kernfs_fop_open+0x86b/0xb30 fs/kernfs/file.c:698
 do_dentry_open+0x793/0x1090 fs/open.c:819
 vfs_open+0x73/0x80 fs/open.c:944
 do_open fs/namei.c:3399 [inline]
 path_openat+0x280f/0x31c0 fs/namei.c:3517
 do_filp_open+0x1e2/0x410 fs/namei.c:3544
 do_sys_openat2+0x19f/0x750 fs/open.c:1219
 do_sys_open fs/open.c:1235 [inline]
 __do_sys_openat fs/open.c:1251 [inline]
 __se_sys_openat fs/open.c:1246 [inline]
 __x64_sys_openat+0x136/0x160 fs/open.c:1246
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:28 [inline]
 free_pages_prepare mm/page_alloc.c:1349 [inline]
 free_pcp_prepare mm/page_alloc.c:1421 [inline]
 free_unref_page_prepare+0x2b7/0x2d0 mm/page_alloc.c:3336
 free_unref_page_list+0x129/0x9c0 mm/page_alloc.c:3443
 release_pages+0xe52/0xea0 mm/swap.c:1103
 free_pages_and_swap_cache+0x86/0xa0 mm/swap_state.c:356
 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:240 [inline]
 tlb_flush_mmu mm/mmu_gather.c:247 [inline]
 tlb_finish_mmu+0x17e/0x310 mm/mmu_gather.c:326
 exit_mmap+0x329/0x590 mm/mmap.c:3387
 __mmput+0x93/0x2f0 kernel/fork.c:1153
 mmput+0x4e/0x150 kernel/fork.c:1176
 exec_mmap fs/exec.c:1040 [inline]
 begin_new_exec+0xb57/0x22f0 fs/exec.c:1287
 load_elf_binary+0x99c/0x28e0 fs/binfmt_elf.c:1001
 search_binary_handler fs/exec.c:1726 [inline]
 exec_binprm fs/exec.c:1767 [inline]
 bprm_execve+0x88b/0x15f0 fs/exec.c:1843
 do_execveat_common+0x918/0xaa0 fs/exec.c:1954
 do_execve fs/exec.c:2024 [inline]
 __do_sys_execve fs/exec.c:2100 [inline]
 __se_sys_execve fs/exec.c:2095 [inline]
 __x64_sys_execve+0x92/0xb0 fs/exec.c:2095
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Memory state around the buggy address:
 ffff888113290f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888113291000: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
>ffff888113291080: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
                                                          ^
 ffff888113291100: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff888113291180: 00 00 00 00 00 00 00 02 fc fc fc fc fc fc fc fc
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