loop4: detected capacity change from 0 to 1024 EXT4-fs (loop4): mounted filesystem 00000000-0000-0000-0000-000000000000 r/w without journal. Quota mode: none. ================================================================== BUG: KASAN: out-of-bounds in ext4_xattr_set_entry+0x94b/0x1e90 fs/ext4/xattr.c:1790 Read of size 18446744073709551588 at addr ffff88803163e040 by task syz.4.5646/25583 CPU: 1 PID: 25583 Comm: syz.4.5646 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xac/0x220 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+0x288/0x290 mm/kasan/generic.c:187 __asan_memmove+0x29/0x70 mm/kasan/shadow.c:94 ext4_xattr_set_entry+0x94b/0x1e90 fs/ext4/xattr.c:1790 ext4_xattr_block_set+0xae3/0x32a0 fs/ext4/xattr.c:2037 ext4_xattr_set_handle+0x10a1/0x1290 fs/ext4/xattr.c:2462 ext4_xattr_set+0x22d/0x320 fs/ext4/xattr.c:2564 __vfs_setxattr+0x431/0x470 fs/xattr.c:201 __vfs_setxattr_noperm+0x12d/0x5e0 fs/xattr.c:235 vfs_setxattr+0x16c/0x2f0 fs/xattr.c:322 do_setxattr fs/xattr.c:630 [inline] path_setxattr+0x362/0x550 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:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7ff360f8eec9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ff361ee2038 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd RAX: ffffffffffffffda RBX: 00007ff3611e5fa0 RCX: 00007ff360f8eec9 RDX: 0000200000000800 RSI: 0000200000000180 RDI: 00002000000001c0 RBP: 00007ff361011f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000361 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff3611e6038 R14: 00007ff3611e5fa0 R15: 00007ffcc96a0ef8 Allocated by task 25583: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:383 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+0x9e5/0x32a0 fs/ext4/xattr.c:1985 ext4_xattr_set_handle+0x10a1/0x1290 fs/ext4/xattr.c:2462 ext4_xattr_set+0x22d/0x320 fs/ext4/xattr.c:2564 __vfs_setxattr+0x431/0x470 fs/xattr.c:201 __vfs_setxattr_noperm+0x12d/0x5e0 fs/xattr.c:235 vfs_setxattr+0x16c/0x2f0 fs/xattr.c:322 do_setxattr fs/xattr.c:630 [inline] path_setxattr+0x362/0x550 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:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 kvfree_call_rcu+0xee/0x780 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+0xa45/0x15b0 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:45 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 __call_rcu_common kernel/rcu/tree.c:2721 [inline] call_rcu+0x158/0x930 kernel/rcu/tree.c:2837 netdev_for_each_tx_queue include/linux/netdevice.h:2520 [inline] dev_shutdown+0x96/0x440 net/sched/sch_generic.c:1489 unregister_netdevice_many_notify+0x8d2/0x1810 net/core/dev.c:11076 unregister_netdevice_many net/core/dev.c:11142 [inline] default_device_exit_batch+0x9cb/0xa60 net/core/dev.c:11620 ops_exit_list net/core/net_namespace.c:178 [inline] cleanup_net+0x77f/0xb90 net/core/net_namespace.c:652 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 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 ffff88803163e000 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 64 bytes inside of 1024-byte region [ffff88803163e000, ffff88803163e400) The buggy address belongs to the physical page: page:ffffea0000c58e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x31638 head:ffffea0000c58e00 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 ffff888017841dc0 ffffea0001e6b600 dead000000000002 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 11554, tgid 11553 (syz.0.2167), ts 306921130511, free_ts 306861893310 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554 prep_new_page mm/page_alloc.c:1561 [inline] get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457 alloc_slab_page+0x5d/0x170 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2e0 mm/slub.c:2081 ___slab_alloc+0xc6d/0x1300 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+0x1a2/0x260 mm/slub.c:3534 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa4/0x240 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+0x159e/0x1650 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+0xbed/0x14b0 net/ipv6/ndisc.c:513 addrconf_rs_timer+0x2bc/0x600 net/ipv6/addrconf.c:4006 call_timer_fn+0x16e/0x530 kernel/time/timer.c:1700 expire_timers kernel/time/timer.c:1751 [inline] __run_timers+0x52d/0x7d0 kernel/time/timer.c:2022 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2035 handle_softirqs+0x280/0x820 kernel/softirq.c:578 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1154 [inline] free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429 discard_slab mm/slub.c:2127 [inline] __unfreeze_partials+0x1cf/0x210 mm/slub.c:2667 put_cpu_partial+0x17c/0x250 mm/slub.c:2743 __slab_free+0x31d/0x410 mm/slub.c:3700 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] kmem_cache_alloc_node+0x150/0x330 mm/slub.c:3540 __alloc_skb+0x108/0x2c0 net/core/skbuff.c:640 alloc_skb include/linux/skbuff.h:1284 [inline] netlink_alloc_large_skb net/netlink/af_netlink.c:1184 [inline] netlink_sendmsg+0x65b/0xbe0 net/netlink/af_netlink.c:1869 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x46a/0x620 net/socket.c:2201 __do_sys_sendto net/socket.c:2213 [inline] __se_sys_sendto net/socket.c:2209 [inline] __x64_sys_sendto+0xde/0xf0 net/socket.c:2209 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff88803163df00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88803163df80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88803163e000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff88803163e080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88803163e100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================