================================================================== BUG: KASAN: out-of-bounds in ext4_xattr_set_entry+0x8e9/0x1e20 fs/ext4/xattr.c:1783 Read of size 18446744073709551588 at addr ffff88807bf4e840 by task syz.0.79/6209 CPU: 0 UID: 0 PID: 6209 Comm: syz.0.79 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/13/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xba/0x230 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x264/0x2c0 mm/kasan/generic.c:200 __asan_memmove+0x29/0x70 mm/kasan/shadow.c:94 ext4_xattr_set_entry+0x8e9/0x1e20 fs/ext4/xattr.c:1783 ext4_xattr_block_set+0x878/0x2ad0 fs/ext4/xattr.c:2030 ext4_xattr_set_handle+0x1286/0x14c0 fs/ext4/xattr.c:2457 ext4_xattr_set+0x255/0x340 fs/ext4/xattr.c:2559 __vfs_setxattr+0x43c/0x480 fs/xattr.c:200 __vfs_setxattr_noperm+0x12d/0x660 fs/xattr.c:234 vfs_setxattr+0x163/0x360 fs/xattr.c:321 do_setxattr fs/xattr.c:636 [inline] filename_setxattr+0x296/0x630 fs/xattr.c:664 path_setxattrat+0x3eb/0x440 fs/xattr.c:708 __do_sys_lsetxattr fs/xattr.c:749 [inline] __se_sys_lsetxattr fs/xattr.c:745 [inline] __x64_sys_lsetxattr+0xbf/0xe0 fs/xattr.c:745 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f4b23f9aeb9 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:00007fff9ae40e58 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd RAX: ffffffffffffffda RBX: 00007f4b24215fa0 RCX: 00007f4b23f9aeb9 RDX: 0000200000000000 RSI: 0000200000000180 RDI: 00002000000001c0 RBP: 00007f4b24008c1f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000361 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4b24215fac R14: 00007f4b24215fa0 R15: 00007f4b24215fa0 Allocated by task 6209: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __do_kmalloc_node mm/slub.c:5170 [inline] __kmalloc_node_track_caller_noprof+0x4db/0x7b0 mm/slub.c:5278 kmemdup_noprof+0x2b/0x70 mm/util.c:138 kmemdup_noprof include/linux/fortify-string.h:763 [inline] ext4_xattr_block_set+0x787/0x2ad0 fs/ext4/xattr.c:1978 ext4_xattr_set_handle+0x1286/0x14c0 fs/ext4/xattr.c:2457 ext4_xattr_set+0x255/0x340 fs/ext4/xattr.c:2559 __vfs_setxattr+0x43c/0x480 fs/xattr.c:200 __vfs_setxattr_noperm+0x12d/0x660 fs/xattr.c:234 vfs_setxattr+0x163/0x360 fs/xattr.c:321 do_setxattr fs/xattr.c:636 [inline] filename_setxattr+0x296/0x630 fs/xattr.c:664 path_setxattrat+0x3eb/0x440 fs/xattr.c:708 __do_sys_lsetxattr fs/xattr.c:749 [inline] __se_sys_lsetxattr fs/xattr.c:745 [inline] __x64_sys_lsetxattr+0xbf/0xe0 fs/xattr.c:745 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88807bf4e800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 64 bytes inside of 1024-byte region [ffff88807bf4e800, ffff88807bf4ec00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88807bf4d000 pfn:0x7bf48 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000240 ffff88813ffa6dc0 ffffea0001f92410 ffffea0000d27810 raw: ffff88807bf4d000 0000000000100005 00000000f5000000 0000000000000000 head: 00fff00000000240 ffff88813ffa6dc0 ffffea0001f92410 ffffea0000d27810 head: ffff88807bf4d000 0000000000100005 00000000f5000000 0000000000000000 head: 00fff00000000003 ffffea0001efd201 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5908, tgid 5908 (syz-executor), ts 84827813931, free_ts 65115537414 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x231/0x280 mm/page_alloc.c:1883 prep_new_page mm/page_alloc.c:1891 [inline] get_page_from_freelist+0x24dc/0x2580 mm/page_alloc.c:3956 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5244 alloc_slab_page mm/slub.c:3235 [inline] allocate_slab+0x7b/0x660 mm/slub.c:3408 new_slab mm/slub.c:3466 [inline] refill_objects+0x33a/0x3d0 mm/slub.c:7077 refill_sheaf mm/slub.c:2784 [inline] __pcs_replace_empty_main+0x2b9/0x620 mm/slub.c:4529 alloc_from_pcs mm/slub.c:4632 [inline] slab_alloc_node mm/slub.c:4766 [inline] __kmalloc_cache_noprof+0x392/0x660 mm/slub.c:5285 kmalloc_noprof include/linux/slab.h:962 [inline] kzalloc_noprof include/linux/slab.h:1204 [inline] rxrpc_service_prealloc+0x9f/0x130 net/rxrpc/call_accept.c:167 rxrpc_listen+0x1c8/0x370 net/rxrpc/af_rxrpc.c:236 afs_open_socket+0x2fa/0x3f0 fs/afs/rxrpc.c:107 afs_net_init+0x67d/0x880 fs/afs/main.c:116 ops_init+0x35c/0x5c0 net/core/net_namespace.c:137 setup_net+0x118/0x340 net/core/net_namespace.c:446 copy_net_ns+0x50e/0x730 net/core/net_namespace.c:581 create_new_namespaces+0x3e7/0x6a0 kernel/nsproxy.c:130 unshare_nsproxy_namespaces+0x11a/0x160 kernel/nsproxy.c:226 page last free pid 5680 tgid 5680 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1432 [inline] __free_frozen_pages+0xc01/0xd80 mm/page_alloc.c:2972 __slab_free+0x263/0x2b0 mm/slub.c:5483 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4452 [inline] slab_alloc_node mm/slub.c:4781 [inline] kmem_cache_alloc_noprof+0x2bc/0x650 mm/slub.c:4788 alloc_buffer_head+0x2a/0x270 fs/buffer.c:3030 folio_alloc_buffers+0x32c/0x640 fs/buffer.c:936 create_empty_buffers+0x3a/0x530 fs/buffer.c:1692 ext4_block_write_begin+0x579/0x1950 fs/ext4/inode.c:1178 ext4_da_write_begin+0x86a/0xd30 fs/ext4/inode.c:3146 generic_perform_write+0x2e2/0x8f0 mm/filemap.c:4314 ext4_buffered_write_iter+0xce/0x3a0 fs/ext4/file.c:300 ext4_file_write_iter+0x298/0x1bf0 fs/ext4/file.c:-1 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x61d/0xb90 fs/read_write.c:688 ksys_write+0x150/0x270 fs/read_write.c:740 Memory state around the buggy address: ffff88807bf4e700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807bf4e780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88807bf4e800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff88807bf4e880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88807bf4e900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================