================================================================== BUG: KASAN: out-of-bounds in ext4_xattr_set_entry+0x965/0x1e90 fs/ext4/xattr.c:1730 Read of size 18446744073709551572 at addr ffff888059c9d050 by task syz.3.292/5503 CPU: 1 PID: 5503 Comm: syz.3.292 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x210 mm/kasan/report.c:420 kasan_report+0x10b/0x140 mm/kasan/report.c:524 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x235/0x290 mm/kasan/generic.c:189 memmove+0x25/0x60 mm/kasan/shadow.c:54 ext4_xattr_set_entry+0x965/0x1e90 fs/ext4/xattr.c:1730 ext4_xattr_block_set+0xae4/0x32b0 fs/ext4/xattr.c:1977 ext4_xattr_move_to_block fs/ext4/xattr.c:2611 [inline] ext4_xattr_make_inode_space fs/ext4/xattr.c:2686 [inline] ext4_expand_extra_isize_ea+0x120b/0x1dc0 fs/ext4/xattr.c:2774 __ext4_expand_extra_isize+0x301/0x3e0 fs/ext4/inode.c:6003 ext4_try_to_expand_extra_isize fs/ext4/inode.c:6046 [inline] __ext4_mark_inode_dirty+0x47f/0x770 fs/ext4/inode.c:6124 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6156 __mark_inode_dirty+0x2eb/0xe90 fs/fs-writeback.c:2449 generic_update_time fs/inode.c:1946 [inline] inode_update_time fs/inode.c:1959 [inline] __file_update_time+0x21d/0x240 fs/inode.c:2147 file_modified_flags+0x390/0x440 fs/inode.c:2220 ext4_write_checks+0x240/0x2c0 fs/ext4/file.c:264 ext4_buffered_write_iter+0xad/0x390 fs/ext4/file.c:280 ext4_file_write_iter+0x1cf/0x1710 fs/ext4/file.c:-1 do_iter_readv_writev fs/read_write.c:-1 [inline] do_iter_write+0x642/0xb10 fs/read_write.c:861 iter_file_splice_write+0x699/0xcc0 fs/splice.c:685 do_splice_from fs/splice.c:763 [inline] direct_splice_actor+0xe1/0x130 fs/splice.c:950 splice_direct_to_actor+0x48b/0xb90 fs/splice.c:896 do_splice_direct+0x1ce/0x2f0 fs/splice.c:1002 do_sendfile+0x5f3/0xea0 fs/read_write.c:1255 __do_sys_sendfile64 fs/read_write.c:1323 [inline] __se_sys_sendfile64+0x141/0x1a0 fs/read_write.c:1309 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f889619ce59 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:00007f8897003028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f8896415fa0 RCX: 00007f889619ce59 RDX: 0000000000000000 RSI: 0000000000000006 RDI: 0000000000000005 RBP: 00007f8896232d6f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000020fffe82 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f8896416038 R14: 00007f8896415fa0 R15: 00007fffcdc42aa8 Allocated by task 5503: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:384 kasan_kmalloc include/linux/kasan.h:211 [inline] __do_kmalloc_node mm/slab_common.c:936 [inline] __kmalloc_node_track_caller+0xae/0x230 mm/slab_common.c:956 kmemdup+0x27/0x60 mm/util.c:129 kmemdup include/linux/fortify-string.h:585 [inline] ext4_xattr_block_set+0x9e6/0x32b0 fs/ext4/xattr.c:1925 ext4_xattr_move_to_block fs/ext4/xattr.c:2611 [inline] ext4_xattr_make_inode_space fs/ext4/xattr.c:2686 [inline] ext4_expand_extra_isize_ea+0x120b/0x1dc0 fs/ext4/xattr.c:2774 __ext4_expand_extra_isize+0x301/0x3e0 fs/ext4/inode.c:6003 ext4_try_to_expand_extra_isize fs/ext4/inode.c:6046 [inline] __ext4_mark_inode_dirty+0x47f/0x770 fs/ext4/inode.c:6124 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6156 __mark_inode_dirty+0x2eb/0xe90 fs/fs-writeback.c:2449 generic_update_time fs/inode.c:1946 [inline] inode_update_time fs/inode.c:1959 [inline] __file_update_time+0x21d/0x240 fs/inode.c:2147 file_modified_flags+0x390/0x440 fs/inode.c:2220 ext4_write_checks+0x240/0x2c0 fs/ext4/file.c:264 ext4_buffered_write_iter+0xad/0x390 fs/ext4/file.c:280 ext4_file_write_iter+0x1cf/0x1710 fs/ext4/file.c:-1 do_iter_readv_writev fs/read_write.c:-1 [inline] do_iter_write+0x642/0xb10 fs/read_write.c:861 iter_file_splice_write+0x699/0xcc0 fs/splice.c:685 do_splice_from fs/splice.c:763 [inline] direct_splice_actor+0xe1/0x130 fs/splice.c:950 splice_direct_to_actor+0x48b/0xb90 fs/splice.c:896 do_splice_direct+0x1ce/0x2f0 fs/splice.c:1002 do_sendfile+0x5f3/0xea0 fs/read_write.c:1255 __do_sys_sendfile64 fs/read_write.c:1323 [inline] __se_sys_sendfile64+0x141/0x1a0 fs/read_write.c:1309 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486 kvfree_call_rcu+0x103/0x870 kernel/rcu/tree.c:3405 neigh_del net/core/neighbour.c:226 [inline] neigh_remove_one+0x5ed/0x700 net/core/neighbour.c:247 neigh_forced_gc net/core/neighbour.c:280 [inline] neigh_alloc net/core/neighbour.c:486 [inline] ___neigh_create+0x46a/0x24c0 net/core/neighbour.c:649 ip6_finish_output2+0x1525/0x15d0 net/ipv6/ip6_output.c:129 dst_output include/net/dst.h:453 [inline] NF_HOOK include/linux/netfilter.h:302 [inline] ndisc_send_skb+0xbf1/0x14e0 net/ipv6/ndisc.c:513 addrconf_dad_completed+0x82e/0xd90 net/ipv6/addrconf.c:4296 addrconf_dad_work+0xc5a/0x14f0 net/ipv6/addrconf.c:-1 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 The buggy address belongs to the object at ffff888059c9d000 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 80 bytes inside of 1024-byte region [ffff888059c9d000, ffff888059c9d400) The buggy address belongs to the physical page: page:ffffea0001672600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x59c98 head:ffffea0001672600 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000001 ffff888017441dc0 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 0x52a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 4270, tgid 4270 (syz-executor), ts 58384115328, free_ts 12556959942 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2559 prep_new_page mm/page_alloc.c:2566 [inline] get_page_from_freelist+0x1a1e/0x1ab0 mm/page_alloc.c:4357 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5657 alloc_slab_page+0x5d/0x160 mm/slub.c:1799 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2c0 mm/slub.c:1997 ___slab_alloc+0xbc6/0x1240 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] __kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3398 kmalloc_trace+0x26/0xe0 mm/slab_common.c:1026 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] batadv_hardif_add_interface net/batman-adv/hard-interface.c:876 [inline] batadv_hard_if_event+0xd8b/0x1550 net/batman-adv/hard-interface.c:964 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:455 call_netdevice_notifiers_extack net/core/dev.c:2052 [inline] call_netdevice_notifiers net/core/dev.c:2066 [inline] register_netdevice+0x163f/0x1b10 net/core/dev.c:10276 br_dev_newlink+0x23/0x100 net/bridge/br_netlink.c:1499 rtnl_newlink_create net/core/rtnetlink.c:3427 [inline] __rtnl_newlink net/core/rtnetlink.c:3647 [inline] rtnl_newlink+0x151e/0x20a0 net/core/rtnetlink.c:3660 rtnetlink_rcv_msg+0x87c/0xfc0 net/core/rtnetlink.c:6157 netlink_rcv_skb+0x1fb/0x450 net/netlink/af_netlink.c:2511 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x74d/0x8d0 net/netlink/af_netlink.c:1344 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1486 [inline] free_pcp_prepare mm/page_alloc.c:1536 [inline] free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3413 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3508 free_contig_range+0x9d/0x150 mm/page_alloc.c:9625 destroy_args+0xf0/0xa0a mm/debug_vm_pgtable.c:1031 debug_vm_pgtable+0x33c/0x38e mm/debug_vm_pgtable.c:1359 do_one_initcall+0x26a/0x840 init/main.c:1310 do_initcall_level+0x137/0x1e4 init/main.c:1383 do_initcalls+0x4b/0x8a init/main.c:1399 kernel_init_freeable+0x415/0x5be init/main.c:1638 kernel_init+0x19/0x1b0 init/main.c:1526 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Memory state around the buggy address: ffff888059c9cf00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888059c9cf80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff888059c9d000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff888059c9d080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888059c9d100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================