loop4: rw=524288, sector=88, nr_sectors = 48 limit=16 syz.4.62: attempt to access beyond end of device loop4: rw=524288, sector=8, nr_sectors = 80 limit=16 ================================================================== BUG: KASAN: slab-out-of-bounds in memcpy_to_page include/linux/highmem.h:403 [inline] BUG: KASAN: slab-out-of-bounds in z_erofs_transform_plain+0x3a4/0x490 fs/erofs/decompressor.c:346 Read of size 4096 at addr ffff0000d3207000 by task syz.4.62/4712 CPU: 0 PID: 4712 Comm: syz.4.62 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call trace: dump_backtrace+0x1c0/0x1ec arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf4/0x15c lib/dump_stack.c:106 print_address_description+0x88/0x218 mm/kasan/report.c:316 print_report+0x50/0x68 mm/kasan/report.c:420 kasan_report+0xa8/0xfc mm/kasan/report.c:524 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x258/0x290 mm/kasan/generic.c:189 memcpy+0x48/0x90 mm/kasan/shadow.c:65 memcpy_to_page include/linux/highmem.h:403 [inline] z_erofs_transform_plain+0x3a4/0x490 fs/erofs/decompressor.c:346 z_erofs_decompress+0x9c/0xd4 fs/erofs/decompressor.c:434 z_erofs_decompress_pcluster fs/erofs/zdata.c:1159 [inline] z_erofs_decompress_queue+0x100c/0x1b40 fs/erofs/zdata.c:1240 z_erofs_runqueue+0x152c/0x16cc fs/erofs/zdata.c:1603 z_erofs_read_folio+0x2d8/0x5c8 fs/erofs/zdata.c:1693 filemap_read_folio+0x134/0x384 mm/filemap.c:2490 filemap_fault+0x98c/0xe98 mm/filemap.c:3340 __do_fault+0x11c/0x3d8 mm/memory.c:4278 do_read_fault mm/memory.c:4629 [inline] do_fault mm/memory.c:4758 [inline] handle_pte_fault mm/memory.c:5029 [inline] __handle_mm_fault mm/memory.c:5171 [inline] handle_mm_fault+0x1cac/0x2fb0 mm/memory.c:5292 __do_page_fault arch/arm64/mm/fault.c:499 [inline] do_page_fault+0x310/0x98c arch/arm64/mm/fault.c:583 do_translation_fault+0x94/0xc8 arch/arm64/mm/fault.c:667 do_mem_abort+0x70/0x194 arch/arm64/mm/fault.c:804 el1_abort+0x3c/0x5c arch/arm64/kernel/entry-common.c:367 el1h_64_sync_handler+0x50/0xac arch/arm64/kernel/entry-common.c:427 el1h_64_sync+0x64/0x68 arch/arm64/kernel/entry.S:580 __arch_copy_from_user+0x1b4/0x230 arch/arm64/lib/copy_template.S:164 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585 Allocated by task 1: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:53 kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:505 __kasan_slab_alloc+0x70/0x88 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x74/0x430 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc+0x22c/0x308 mm/slub.c:3383 kmem_cache_zalloc include/linux/slab.h:689 [inline] __kernfs_new_node+0xec/0x5f4 fs/kernfs/dir.c:614 kernfs_new_node+0x11c/0x22c fs/kernfs/dir.c:690 __kernfs_create_file+0x60/0x2d4 fs/kernfs/file.c:1068 sysfs_add_file_mode_ns+0x1d8/0x294 fs/sysfs/file.c:294 create_files fs/sysfs/group.c:64 [inline] internal_create_group+0x3e0/0xad0 fs/sysfs/group.c:148 internal_create_groups fs/sysfs/group.c:188 [inline] sysfs_create_groups+0x60/0x134 fs/sysfs/group.c:214 device_add_groups drivers/base/core.c:2752 [inline] device_add_attrs+0xd8/0x6f4 drivers/base/core.c:2900 device_add+0x5d0/0xf90 drivers/base/core.c:3648 netdev_register_kobject+0x164/0x2e0 net/core/net-sysfs.c:2013 register_netdevice+0xf1c/0x1614 net/core/dev.c:10243 register_netdev+0x48/0x64 net/core/dev.c:10371 nr_proto_init+0x168/0x704 net/netrom/af_netrom.c:1425 do_one_initcall+0x278/0x9e0 init/main.c:1310 do_initcall_level+0x154/0x214 init/main.c:1383 do_initcalls+0x58/0xac init/main.c:1399 do_basic_setup+0x8c/0xa0 init/main.c:1418 kernel_init_freeable+0x35c/0x4f0 init/main.c:1638 kernel_init+0x24/0x1d8 init/main.c:1526 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:850 The buggy address belongs to the object at ffff0000d3207000 which belongs to the cache kernfs_node_cache of size 168 The buggy address is located 0 bytes inside of 168-byte region [ffff0000d3207000, ffff0000d32070a8) The buggy address belongs to the physical page: page:00000000e764ae64 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x113207 flags: 0x5ffc00000000200(slab|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000000200 0000000000000000 dead000000000122 ffff0000c03dca80 raw: 0000000000000000 0000000000110011 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000d3206f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff0000d3207000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff0000d3207080: 00 00 00 00 00 fc fc fc fc fc fc fc fc 00 00 00 ^ ffff0000d3207100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff0000d3207180: 00 00 fc fc fc fc fc fc fc fc 00 00 00 00 00 00 ==================================================================