================================================================== BUG: KASAN: out-of-bounds in ext4_xattr_set_entry+0x94b/0x1e90 fs/ext4/xattr.c:1783 Read of size 18446744073709551588 at addr ffff888074239040 by task syz.4.5959/27015 CPU: 0 PID: 27015 Comm: syz.4.5959 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xa8/0x210 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x241/0x290 mm/kasan/generic.c:187 __asan_memmove+0x29/0x70 mm/kasan/shadow.c:94 ext4_xattr_set_entry+0x94b/0x1e90 fs/ext4/xattr.c:1783 ext4_xattr_block_set+0xae8/0x32b0 fs/ext4/xattr.c:2030 ext4_xattr_set_handle+0x1280/0x14c0 fs/ext4/xattr.c:2452 ext4_xattr_set+0x252/0x340 fs/ext4/xattr.c:2554 __vfs_setxattr+0x431/0x470 fs/xattr.c:201 __vfs_setxattr_noperm+0x12d/0x5e0 fs/xattr.c:235 vfs_setxattr+0x16b/0x2f0 fs/xattr.c:322 do_setxattr fs/xattr.c:630 [inline] path_setxattr+0x3f3/0x5d0 fs/xattr.c:659 __do_sys_lsetxattr fs/xattr.c:684 [inline] __se_sys_lsetxattr fs/xattr.c:680 [inline] __x64_sys_lsetxattr+0xb8/0xd0 fs/xattr.c:680 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f8b8c39aeb9 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:00007f8b8d1e8028 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd RAX: ffffffffffffffda RBX: 00007f8b8c616090 RCX: 00007f8b8c39aeb9 RDX: 0000200000000000 RSI: 0000200000000180 RDI: 00002000000001c0 RBP: 00007f8b8c408c1f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000361 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8b8c616128 R14: 00007f8b8c616090 R15: 00007ffe580e5838 Allocated by task 27015: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:384 kasan_kmalloc include/linux/kasan.h:198 [inline] __do_kmalloc_node mm/slab_common.c:1007 [inline] __kmalloc_node_track_caller+0xb2/0x230 mm/slab_common.c:1027 kmemdup+0x2b/0x70 mm/util.c:131 kmemdup include/linux/fortify-string.h:779 [inline] ext4_xattr_block_set+0x9ea/0x32b0 fs/ext4/xattr.c:1978 ext4_xattr_set_handle+0x1280/0x14c0 fs/ext4/xattr.c:2452 ext4_xattr_set+0x252/0x340 fs/ext4/xattr.c:2554 __vfs_setxattr+0x431/0x470 fs/xattr.c:201 __vfs_setxattr_noperm+0x12d/0x5e0 fs/xattr.c:235 vfs_setxattr+0x16b/0x2f0 fs/xattr.c:322 do_setxattr fs/xattr.c:630 [inline] path_setxattr+0x3f3/0x5d0 fs/xattr.c:659 __do_sys_lsetxattr fs/xattr.c:684 [inline] __se_sys_lsetxattr fs/xattr.c:680 [inline] __x64_sys_lsetxattr+0xb8/0xd0 fs/xattr.c:680 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 kvfree_call_rcu+0xee/0x790 kernel/rcu/tree.c:3452 neigh_periodic_work+0x3f7/0xd70 net/core/neighbour.c:1010 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Second to last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 __call_rcu_common kernel/rcu/tree.c:2721 [inline] call_rcu+0x153/0x950 kernel/rcu/tree.c:2837 rhashtable_rehash_table lib/rhashtable.c:348 [inline] rht_deferred_worker+0x1ad9/0x22a0 lib/rhashtable.c:432 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 The buggy address belongs to the object at ffff888074239000 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 64 bytes inside of 1024-byte region [ffff888074239000, ffff888074239400) The buggy address belongs to the physical page: page:ffffea0001d08e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x74238 head:ffffea0001d08e00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888017c41dc0 dead000000000100 dead000000000122 raw: 0000000000000000 0000000080100010 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 0x152820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL), pid 49, tgid 49 (kworker/u4:3), ts 703819525957, free_ts 696898734721 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1581 prep_new_page mm/page_alloc.c:1588 [inline] get_page_from_freelist+0x1951/0x19e0 mm/page_alloc.c:3220 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4486 alloc_slab_page+0x5d/0x160 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5d/0x12f0 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x19e/0x250 mm/slub.c:3534 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa4/0x230 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:721 [inline] neigh_alloc net/core/neighbour.c:495 [inline] ___neigh_create+0x6d2/0x2440 net/core/neighbour.c:649 ip6_finish_output2+0x1581/0x1630 net/ipv6/ip6_output.c:132 dst_output include/net/dst.h:467 [inline] NF_HOOK include/linux/netfilter.h:304 [inline] ndisc_send_skb+0xc26/0x14f0 net/ipv6/ndisc.c:513 addrconf_dad_completed+0x7ef/0xd90 net/ipv6/addrconf.c:4342 addrconf_dad_work+0xc90/0x1530 net/ipv6/addrconf.c:-1 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1181 [inline] free_unref_page_prepare+0x7b2/0x8c0 mm/page_alloc.c:2365 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2458 vfree+0x1a6/0x320 mm/vmalloc.c:2868 kcov_put kernel/kcov.c:438 [inline] kcov_close+0x2b/0x50 kernel/kcov.c:534 __fput+0x234/0x970 fs/file_table.c:384 task_work_run+0x1d4/0x260 kernel/task_work.c:245 exit_task_work include/linux/task_work.h:43 [inline] do_exit+0x95a/0x2460 kernel/exit.c:883 do_group_exit+0x21b/0x2d0 kernel/exit.c:1024 get_signal+0x12fc/0x13f0 kernel/signal.c:2902 arch_do_signal_or_restart+0xc2/0x800 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff888074238f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888074238f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888074239000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff888074239080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888074239100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================