loop4: rw=524288, sector=88, nr_sectors = 48 limit=16 syz.4.2213: 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+0x39c/0x494 fs/erofs/decompressor.c:347 Read of size 4096 at addr ffff0000e535c000 by task syz.4.2213/11564 CPU: 0 PID: 11564 Comm: syz.4.2213 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/14/2026 Call trace: dump_backtrace+0x1c4/0x1f0 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+0x39c/0x494 fs/erofs/decompressor.c:347 z_erofs_decompress+0x9c/0xd4 fs/erofs/decompressor.c:435 z_erofs_decompress_pcluster fs/erofs/zdata.c:1159 [inline] z_erofs_decompress_queue+0x103c/0x1bf4 fs/erofs/zdata.c:1240 z_erofs_runqueue+0x1508/0x16a8 fs/erofs/zdata.c:1603 z_erofs_read_folio+0x2dc/0x5cc fs/erofs/zdata.c:1693 filemap_read_folio+0x134/0x384 mm/filemap.c:2490 filemap_fault+0x990/0xe98 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+0x1d04/0x3018 mm/memory.c:5292 faultin_page mm/gup.c:1026 [inline] __get_user_pages+0x340/0x770 mm/gup.c:1250 populate_vma_page_range+0x1f4/0x298 mm/gup.c:1607 __mm_populate+0x214/0x338 mm/gup.c:1721 do_mlock+0x420/0x514 mm/mlock.c:608 __do_sys_mlock mm/mlock.c:616 [inline] __se_sys_mlock mm/mlock.c:614 [inline] __arm64_sys_mlock+0x60/0x78 mm/mlock.c:614 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 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 4330: 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+0x234/0x310 mm/slub.c:3383 kmem_cache_zalloc include/linux/slab.h:689 [inline] fill_pool lib/debugobjects.c:169 [inline] debug_objects_fill_pool+0x42c/0x628 lib/debugobjects.c:654 debug_object_activate+0x44/0x4c0 lib/debugobjects.c:743 debug_rcu_head_queue kernel/rcu/rcu.h:190 [inline] call_rcu+0x54/0x958 kernel/rcu/tree.c:2834 security_inode_free+0xc0/0xdc security/security.c:1076 __destroy_inode+0x2f0/0x7ac fs/inode.c:286 destroy_inode fs/inode.c:309 [inline] evict+0x6b0/0x824 fs/inode.c:720 iput_final fs/inode.c:1834 [inline] iput+0x728/0x7e8 fs/inode.c:1860 dentry_unlink_inode+0x360/0x438 fs/dcache.c:405 __dentry_kill+0x318/0x590 fs/dcache.c:611 shrink_dentry_list+0x404/0x7d0 fs/dcache.c:1206 shrink_dcache_parent+0xb0/0x364 fs/dcache.c:-1 d_invalidate+0x10c/0x250 fs/dcache.c:1742 proc_invalidate_siblings_dcache+0x374/0x610 fs/proc/inode.c:148 proc_flush_pid+0x24/0x34 fs/proc/base.c:3449 release_task+0x1348/0x1510 kernel/exit.c:284 wait_task_zombie kernel/exit.c:1216 [inline] wait_consider_task+0x14c4/0x269c kernel/exit.c:1443 do_wait_thread kernel/exit.c:1506 [inline] do_wait+0x328/0xaf8 kernel/exit.c:1623 kernel_wait4+0x1f8/0x318 kernel/exit.c:1786 __do_sys_wait4 kernel/exit.c:1814 [inline] __se_sys_wait4 kernel/exit.c:1810 [inline] __arm64_sys_wait4+0x138/0x2d0 kernel/exit.c:1810 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 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 The buggy address belongs to the object at ffff0000e535c000 which belongs to the cache debug_objects_cache of size 40 The buggy address is located 0 bytes inside of 40-byte region [ffff0000e535c000, ffff0000e535c028) The buggy address belongs to the physical page: page:000000002e852dd1 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff0000e535cd58 pfn:0x12535c flags: 0x5ffc00000000200(slab|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000000200 fffffc0003d76a00 dead000000000002 ffff0000c000cf00 raw: ffff0000e535cd58 000000008049003e 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000e535bf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff0000e535bf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff0000e535c000: 00 00 00 00 00 fc fc 00 00 00 00 00 fc fc 00 00 ^ ffff0000e535c080: 00 00 00 fc fc 00 00 00 00 00 fc fc 00 00 00 00 ffff0000e535c100: 00 fc fc 00 00 00 00 00 fc fc fa fb fb fb fb fc ================================================================== syz.4.2213: attempt to access beyond end of device loop4: rw=0, sector=34359738360, nr_sectors = 8 limit=16 syz.4.2213: attempt to access beyond end of device loop4: rw=0, sector=34359738360, nr_sectors = 8 limit=16 syz.4.2213: attempt to access beyond end of device loop4: rw=0, sector=34359738360, nr_sectors = 8 limit=16 syz.4.2213: attempt to access beyond end of device loop4: rw=0, sector=34359738360, nr_sectors = 8 limit=16 syz.4.2213: attempt to access beyond end of device loop4: rw=0, sector=34359738360, nr_sectors = 8 limit=16 syz.4.2213: attempt to access beyond end of device loop4: rw=0, sector=34359738360, nr_sectors = 8 limit=16 syz.4.2213: attempt to access beyond end of device loop4: rw=0, sector=34359738360, nr_sectors = 8 limit=16