==================================================================
BUG: KASAN: use-after-free in xattr_find_entry fs/ext4/xattr.c:294 [inline]
BUG: KASAN: use-after-free in ext4_xattr_ibody_get+0x62e/0x690 fs/ext4/xattr.c:601
Read of size 4 at addr ffff88810ea30004 by task syz.1.63/557

CPU: 0 PID: 557 Comm: syz.1.63 Tainted: G        W         syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
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
 xattr_find_entry fs/ext4/xattr.c:294 [inline]
 ext4_xattr_ibody_get+0x62e/0x690 fs/ext4/xattr.c:601
 ext4_xattr_get+0x116/0x820 fs/ext4/xattr.c:655
 ext4_get_acl+0x6c/0x660 fs/ext4/acl.c:162
 get_acl+0x15f/0x270 fs/posix_acl.c:141
 posix_acl_chmod+0xe4/0x240 fs/posix_acl.c:565
 ext4_setattr+0x9fa/0x1760 fs/ext4/inode.c:5722
 notify_change+0xab3/0xe40 fs/attr.c:410
 chmod_common+0x1e1/0x390 fs/open.c:584
 do_fchmodat+0xd4/0x1a0 fs/open.c:622
 __do_sys_fchmodat fs/open.c:635 [inline]
 __se_sys_fchmodat fs/open.c:632 [inline]
 __x64_sys_fchmodat+0x7b/0x90 fs/open.c:632
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f77ebc32629
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:00007f77ea68d028 EFLAGS: 00000246 ORIG_RAX: 000000000000010c
RAX: ffffffffffffffda RBX: 00007f77ebeabfa0 RCX: 00007f77ebc32629
RDX: 000000000000017f RSI: 0000200000000300 RDI: ffffffffffffff9c
RBP: 00007f77ebcc8b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f77ebeac038 R14: 00007f77ebeabfa0 R15: 00007ffd94072cb8

Allocated by task 276:
 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_slab_alloc+0xbd/0xf0 mm/kasan/common.c:463
 kasan_slab_alloc include/linux/kasan.h:244 [inline]
 slab_post_alloc_hook+0x5d/0x2f0 mm/slab.h:580
 slab_alloc_node mm/slub.c:2952 [inline]
 slab_alloc mm/slub.c:2960 [inline]
 kmem_cache_alloc+0x162/0x2d0 mm/slub.c:2965
 kmem_cache_alloc_node include/linux/slab.h:426 [inline]
 alloc_task_struct_node kernel/fork.c:177 [inline]
 dup_task_struct+0x57/0xbd0 kernel/fork.c:912
 copy_process+0x5cd/0x3300 kernel/fork.c:2101
 kernel_clone+0x233/0x960 kernel/fork.c:2650
 __do_sys_clone kernel/fork.c:2776 [inline]
 __se_sys_clone kernel/fork.c:2760 [inline]
 __x64_sys_clone+0x198/0x210 kernel/fork.c:2760
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Freed by task 529:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4a/0x70 mm/kasan/common.c:45
 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370
 ____kasan_slab_free+0x125/0x160 mm/kasan/common.c:362
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:370
 kasan_slab_free include/linux/kasan.h:220 [inline]
 slab_free_hook mm/slub.c:1600 [inline]
 slab_free_freelist_hook+0xc5/0x190 mm/slub.c:1626
 slab_free mm/slub.c:3208 [inline]
 kmem_cache_free+0x100/0x2d0 mm/slub.c:3224
 free_task_struct kernel/fork.c:182 [inline]
 free_task+0xf3/0x230 kernel/fork.c:482
 __put_task_struct+0x2b7/0x420 kernel/fork.c:785
 put_task_struct include/linux/sched/task.h:143 [inline]
 delayed_put_task_struct+0x6f/0x1a0 kernel/exit.c:221
 rcu_do_batch+0x4ef/0xab0 kernel/rcu/tree.c:2494
 rcu_core+0x577/0xd80 kernel/rcu/tree.c:2735
 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2748
 __do_softirq+0x255/0x563 kernel/softirq.c:309

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
 __call_rcu kernel/rcu/tree.c:2980 [inline]
 call_rcu+0x11a/0x10b0 kernel/rcu/tree.c:3054
 put_task_struct_rcu_user kernel/exit.c:227 [inline]
 release_task+0x11a0/0x1200 kernel/exit.c:273
 wait_task_zombie kernel/exit.c:1171 [inline]
 wait_consider_task+0x1802/0x27d0 kernel/exit.c:1398
 do_wait_thread kernel/exit.c:1461 [inline]
 do_wait+0x244/0x6c0 kernel/exit.c:1532
 kernel_wait4+0x1d1/0x2a0 kernel/exit.c:1694
 __do_sys_wait4 kernel/exit.c:1722 [inline]
 __se_sys_wait4 kernel/exit.c:1718 [inline]
 __x64_sys_wait4+0x163/0x230 kernel/exit.c:1718
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

The buggy address belongs to the object at ffff88810ea30000
 which belongs to the cache task_struct of size 4800
The buggy address is located 4 bytes inside of
 4800-byte region [ffff88810ea30000, ffff88810ea312c0)
The buggy address belongs to the page:
page:ffffea00043a8c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x10ea30
head:ffffea00043a8c00 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head)
raw: 4000000000010200 dead000000000100 dead000000000122 ffff888100189500
raw: 0000000000000000 0000000000060006 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 465, ts 37494708745, free_ts 37490603877
 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:5370
 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+0x1ac/0x2d0 mm/slub.c:2965
 kmem_cache_alloc_node include/linux/slab.h:426 [inline]
 alloc_task_struct_node kernel/fork.c:177 [inline]
 dup_task_struct+0x57/0xbd0 kernel/fork.c:912
 copy_process+0x5cd/0x3300 kernel/fork.c:2101
 kernel_clone+0x233/0x960 kernel/fork.c:2650
 __do_sys_clone kernel/fork.c:2776 [inline]
 __se_sys_clone kernel/fork.c:2760 [inline]
 __x64_sys_clone+0x198/0x210 kernel/fork.c:2760
 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_pages_ok+0x80b/0x830 mm/page_alloc.c:1629
 free_the_page mm/page_alloc.c:5431 [inline]
 __free_pages+0xd8/0x3b0 mm/page_alloc.c:5440
 __free_slab+0xcf/0x190 mm/slub.c:1899
 free_slab mm/slub.c:1914 [inline]
 discard_slab mm/slub.c:1920 [inline]
 unfreeze_partials+0x15f/0x190 mm/slub.c:2415
 put_cpu_partial+0xc1/0x180 mm/slub.c:2451
 __slab_free+0x2c9/0x3a0 mm/slub.c:3100
 do_slab_free mm/slub.c:3196 [inline]
 ___cache_free+0x10e/0x130 mm/slub.c:3215
 qlink_free+0x50/0x90 mm/kasan/quarantine.c:157
 qlist_free_all+0x5f/0xb0 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x14a/0x160 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x2f/0xf0 mm/kasan/common.c:440
 kasan_slab_alloc include/linux/kasan.h:244 [inline]
 slab_post_alloc_hook+0x5d/0x2f0 mm/slab.h:580
 slab_alloc_node mm/slub.c:2952 [inline]
 slab_alloc mm/slub.c:2960 [inline]
 kmem_cache_alloc+0x162/0x2d0 mm/slub.c:2965
 getname_flags+0xb9/0x500 fs/namei.c:141
 getname+0x19/0x20 fs/namei.c:212
 do_sys_openat2+0xde/0x750 fs/open.c:1213

Memory state around the buggy address:
 ffff88810ea2ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88810ea2ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88810ea30000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff88810ea30080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88810ea30100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
EXT4-fs error (device loop1): xattr_find_entry:297: inode #12: comm syz.1.63: corrupted xattr entries