loop0: detected capacity change from 0 to 1024 EXT4-fs (loop0): 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:1795 Read of size 18446744073709551588 at addr ffff88801dfe7840 by task syz.0.323/6815 CPU: 0 PID: 6815 Comm: syz.0.323 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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:1795 ext4_xattr_block_set+0xae3/0x32a0 fs/ext4/xattr.c:2042 ext4_xattr_set_handle+0xbff/0x1290 fs/ext4/xattr.c:2467 ext4_xattr_set+0x22d/0x320 fs/ext4/xattr.c:2569 __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_setxattr fs/xattr.c:677 [inline] __se_sys_setxattr fs/xattr.c:673 [inline] __x64_sys_setxattr+0xbb/0xd0 fs/xattr.c:673 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: 0033:0x7fc9c318f749 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:00007fc9c3fdc038 EFLAGS: 00000246 ORIG_RAX: 00000000000000bc RAX: ffffffffffffffda RBX: 00007fc9c33e5fa0 RCX: 00007fc9c318f749 RDX: 00002000000013c0 RSI: 0000200000000140 RDI: 0000200000000100 RBP: 00007fc9c3213f91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000700 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fc9c33e6038 R14: 00007fc9c33e5fa0 R15: 00007ffc50c8f8e8 Allocated by task 6815: 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:1990 ext4_xattr_set_handle+0xbff/0x1290 fs/ext4/xattr.c:2467 ext4_xattr_set+0x22d/0x320 fs/ext4/xattr.c:2569 __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_setxattr fs/xattr.c:677 [inline] __se_sys_setxattr fs/xattr.c:673 [inline] __x64_sys_setxattr+0xbb/0xd0 fs/xattr.c:673 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 The buggy address belongs to the object at ffff88801dfe7800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 64 bytes inside of 1024-byte region [ffff88801dfe7800, ffff88801dfe7c00) The buggy address belongs to the physical page: page:ffffea000077f800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1dfe0 head:ffffea000077f800 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 ffffea0001f40200 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 5765, tgid 5765 (syz-executor), ts 90023777219, free_ts 90022393725 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_pages_node include/linux/gfp.h:237 [inline] alloc_slab_page+0x4f/0x170 mm/slub.c:1883 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_node+0xa4/0x230 mm/slab_common.c:1014 kmalloc_node include/linux/slab.h:620 [inline] kvmalloc_node+0x70/0x180 mm/util.c:617 kvzalloc_node include/linux/slab.h:742 [inline] alloc_shrinker_info+0xf3/0x400 mm/vmscan.c:284 mem_cgroup_css_online+0x2c/0x3e0 mm/memcontrol.c:5471 online_css+0xb9/0x260 kernel/cgroup/cgroup.c:5510 css_create kernel/cgroup/cgroup.c:5581 [inline] cgroup_apply_control_enable+0x804/0xb00 kernel/cgroup/cgroup.c:3218 cgroup_mkdir+0xbeb/0xde0 kernel/cgroup/cgroup.c:5778 kernfs_iop_mkdir+0x250/0x3d0 fs/kernfs/dir.c:1246 vfs_mkdir+0x296/0x440 fs/namei.c:4121 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] deactivate_slab+0x38c/0x410 mm/slub.c:2604 ___slab_alloc+0x5a6/0x1300 mm/slub.c:3202 __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 kmalloc_node_trace+0x26/0xe0 mm/slab_common.c:1111 kmalloc_node include/linux/slab.h:616 [inline] kzalloc_node include/linux/slab.h:732 [inline] alloc_mem_cgroup_per_node_info mm/memcontrol.c:5291 [inline] mem_cgroup_alloc mm/memcontrol.c:5374 [inline] mem_cgroup_css_alloc+0x51b/0x15c0 mm/memcontrol.c:5418 css_create kernel/cgroup/cgroup.c:5560 [inline] cgroup_apply_control_enable+0x3cc/0xb00 kernel/cgroup/cgroup.c:3218 cgroup_mkdir+0xbeb/0xde0 kernel/cgroup/cgroup.c:5778 kernfs_iop_mkdir+0x250/0x3d0 fs/kernfs/dir.c:1246 vfs_mkdir+0x296/0x440 fs/namei.c:4121 do_mkdirat+0x1d4/0x440 fs/namei.c:4144 __do_sys_mkdirat fs/namei.c:4159 [inline] __se_sys_mkdirat fs/namei.c:4157 [inline] __x64_sys_mkdirat+0x89/0xa0 fs/namei.c:4157 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: ffff88801dfe7700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88801dfe7780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88801dfe7800: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ^ ffff88801dfe7880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88801dfe7900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================