================================================================== BUG: KASAN: out-of-bounds in ext4_xattr_set_entry+0xa27/0x1eb0 fs/ext4/xattr.c:1710 Read of size 18446744073709551600 at addr ffff888050c91eb8 by task syz.0.35/4527 CPU: 1 PID: 4527 Comm: syz.0.35 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 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+0xa27/0x1eb0 fs/ext4/xattr.c:1710 ext4_xattr_ibody_set+0x25e/0x700 fs/ext4/xattr.c:2217 ext4_destroy_inline_data_nolock+0x237/0x5f0 fs/ext4/inline.c:468 ext4_convert_inline_data_nolock+0x3b0/0x9e0 fs/ext4/inline.c:1258 ext4_convert_inline_data+0x470/0x5b0 fs/ext4/inline.c:2127 ext4_page_mkwrite+0x1c4/0x10d0 fs/ext4/inode.c:6278 do_page_mkwrite+0x16b/0x5c0 mm/memory.c:3009 wp_page_shared+0x167/0x370 mm/memory.c:3358 handle_pte_fault mm/memory.c:5047 [inline] __handle_mm_fault mm/memory.c:5171 [inline] handle_mm_fault+0x1b1b/0x3d40 mm/memory.c:5292 do_user_addr_fault+0x58e/0xb20 arch/x86/mm/fault.c:1338 handle_page_fault arch/x86/mm/fault.c:1429 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 RIP: 0033:0x7f13fbd6cd58 Code: fc 89 37 c3 c5 fa 6f 06 c5 fa 6f 4c 16 f0 c5 fa 7f 07 c5 fa 7f 4c 17 f0 c3 66 0f 1f 84 00 00 00 00 00 48 8b 4c 16 f8 48 8b 36 <48> 89 37 48 89 4c 17 f8 c3 c5 fe 6f 54 16 e0 c5 fe 6f 5c 16 c0 c5 RSP: 002b:00007ffd6b98ca08 EFLAGS: 00010246 RAX: 00002000000002c0 RBX: 0000000000000004 RCX: 0030656c69662f2e RDX: 0000000000000008 RSI: 0030656c69662f2e RDI: 00002000000002c0 RBP: fffffffffffffffe R08: 0000001b2e820000 R09: 0000000000000001 R10: 7ffffffffffffff7 R11: 0000000000000009 R12: 00007ffd6b98cb30 R13: 00007f13fc025fac R14: 000000000001461e R15: 00007f13fc025fa0 The buggy address belongs to the physical page: page:ffffea0001432440 refcount:2 mapcount:0 mapping:ffff888140c8ca00 index:0x2 pfn:0x50c91 memcg:ffff888055764000 aops:def_blk_aops ino:700000 flags: 0xfff9800000205a(referenced|dirty|lru|workingset|private|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff9800000205a ffffea0001521048 ffffea0001d5eb48 ffff888140c8ca00 raw: 0000000000000002 ffff888056b6c910 00000002ffffffff ffff888055764000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Movable, gfp_mask 0x148c48(GFP_NOFS|__GFP_NOFAIL|__GFP_COMP|__GFP_HARDWALL|__GFP_MOVABLE), pid 4527, tgid 4527 (syz.0.35), ts 84717886686, free_ts 84717070913 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2560 prep_new_page mm/page_alloc.c:2567 [inline] get_page_from_freelist+0x206b/0x2180 mm/page_alloc.c:4358 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5658 folio_alloc+0x1c/0x60 mm/mempolicy.c:2292 filemap_alloc_folio+0xdb/0x480 mm/filemap.c:999 __filemap_get_folio+0x6ba/0xde0 mm/filemap.c:1993 pagecache_get_page+0x26/0x260 mm/folio-compat.c:110 find_or_create_page include/linux/pagemap.h:648 [inline] grow_dev_page fs/buffer.c:946 [inline] grow_buffers fs/buffer.c:1011 [inline] __getblk_slow fs/buffer.c:1038 [inline] __getblk_gfp+0x2a0/0xa80 fs/buffer.c:1333 sb_getblk include/linux/buffer_head.h:356 [inline] __ext4_get_inode_loc+0x45f/0xd60 fs/ext4/inode.c:4525 ext4_get_inode_loc fs/ext4/inode.c:4653 [inline] ext4_reserve_inode_write+0x10a/0x290 fs/ext4/inode.c:5942 __ext4_mark_inode_dirty+0x161/0x760 fs/ext4/inode.c:6119 ext4_dirty_inode+0xbf/0x100 fs/ext4/inode.c:6156 __mark_inode_dirty+0x2e7/0xe80 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_update_time+0x2f3/0x370 fs/inode.c:2178 ext4_page_mkwrite+0x1a9/0x10d0 fs/ext4/inode.c:6274 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1487 [inline] free_pcp_prepare mm/page_alloc.c:1537 [inline] free_unref_page_prepare+0x8e5/0x9e0 mm/page_alloc.c:3414 free_unref_page_list+0xbb/0x8e0 mm/page_alloc.c:3555 release_pages+0x20d1/0x2340 mm/swap.c:1035 tlb_batch_pages_flush mm/mmu_gather.c:60 [inline] tlb_flush_mmu_free mm/mmu_gather.c:255 [inline] tlb_flush_mmu+0x105/0x220 mm/mmu_gather.c:262 tlb_finish_mmu+0xf0/0x220 mm/mmu_gather.c:394 unmap_region+0x29c/0x300 mm/mmap.c:2343 do_mas_align_munmap+0xcda/0x12d0 mm/mmap.c:2592 do_mas_munmap+0x240/0x2b0 mm/mmap.c:2650 __mmap_region mm/mmap.c:2698 [inline] mmap_region+0x7ab/0x1c50 mm/mmap.c:2916 do_mmap+0x9ce/0x10d0 mm/mmap.c:1436 vm_mmap_pgoff+0x1c1/0x2d0 mm/util.c:520 ksys_mmap_pgoff+0x4bf/0x720 mm/mmap.c:1482 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 Memory state around the buggy address: ffff888050c91d80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888050c91e00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888050c91e80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff888050c91f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888050c91f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================