================================================================== BUG: KASAN: out-of-bounds in ext4_xattr_set_entry+0x965/0x1e90 fs/ext4/xattr.c:1730 Read of size 18446744073709551588 at addr ffff88805767d840 by task syz.4.23/4419 CPU: 1 PID: 4419 Comm: syz.4.23 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 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_set_handle+0xe3b/0x1570 fs/ext4/xattr.c:2399 ext4_xattr_set+0x242/0x320 fs/ext4/xattr.c:2501 __vfs_setxattr+0x3e0/0x420 fs/xattr.c:182 __vfs_setxattr_noperm+0x129/0x5e0 fs/xattr.c:216 vfs_setxattr+0x167/0x2e0 fs/xattr.c:309 do_setxattr fs/xattr.c:594 [inline] setxattr+0x346/0x360 fs/xattr.c:617 path_setxattr+0x147/0x290 fs/xattr.c:636 __do_sys_setxattr fs/xattr.c:652 [inline] __se_sys_setxattr fs/xattr.c:648 [inline] __x64_sys_setxattr+0xb7/0xd0 fs/xattr.c:648 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: 0033:0x7efe8159c799 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:00007efe824e1028 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc RAX: ffffffffffffffda RBX: 00007efe81815fa0 RCX: 00007efe8159c799 RDX: 00002000000013c0 RSI: 0000200000000140 RDI: 0000200000000100 RBP: 00007efe81632c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000700 R11: 0000000000000246 R12: 0000000000000000 R13: 00007efe81816038 R14: 00007efe81815fa0 R15: 00007ffebde18cb8 Allocated by task 4419: 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_set_handle+0xe3b/0x1570 fs/ext4/xattr.c:2399 ext4_xattr_set+0x242/0x320 fs/ext4/xattr.c:2501 __vfs_setxattr+0x3e0/0x420 fs/xattr.c:182 __vfs_setxattr_noperm+0x129/0x5e0 fs/xattr.c:216 vfs_setxattr+0x167/0x2e0 fs/xattr.c:309 do_setxattr fs/xattr.c:594 [inline] setxattr+0x346/0x360 fs/xattr.c:617 path_setxattr+0x147/0x290 fs/xattr.c:636 __do_sys_setxattr fs/xattr.c:652 [inline] __se_sys_setxattr fs/xattr.c:648 [inline] __x64_sys_setxattr+0xb7/0xd0 fs/xattr.c:648 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 The buggy address belongs to the object at ffff88805767d800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 64 bytes inside of 1024-byte region [ffff88805767d800, ffff88805767dc00) The buggy address belongs to the physical page: page:ffffea00015d9e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x57678 head:ffffea00015d9e00 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 4276, tgid 4276 (syz-executor), ts 68753683533, free_ts 17130962612 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/0x1b00 net/core/dev.c:10263 veth_newlink+0x830/0xc80 drivers/net/veth.c:1756 rtnl_newlink_create net/core/rtnetlink.c:3422 [inline] __rtnl_newlink net/core/rtnetlink.c:3642 [inline] rtnl_newlink+0x1542/0x2080 net/core/rtnetlink.c:3655 rtnetlink_rcv_msg+0x87c/0xfc0 net/core/rtnetlink.c:6150 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: ffff88805767d700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805767d780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88805767d800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff88805767d880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88805767d900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================