================================================================== BUG: KASAN: slab-out-of-bounds in memcpy_from_page include/linux/highmem.h:423 [inline] BUG: KASAN: slab-out-of-bounds in hfs_bnode_read+0x16a/0x200 fs/hfs/bnode.c:35 Write of size 94 at addr ffff888025a0ec80 by task syz.0.100/6580 CPU: 1 UID: 0 PID: 6580 Comm: syz.0.100 Not tainted 6.15.0-rc1-syzkaller-00301-g3bde70a2c827 #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0x16e/0x5b0 mm/kasan/report.c:521 kasan_report+0x143/0x180 mm/kasan/report.c:634 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x28f/0x2a0 mm/kasan/generic.c:189 __asan_memcpy+0x40/0x70 mm/kasan/shadow.c:106 memcpy_from_page include/linux/highmem.h:423 [inline] hfs_bnode_read+0x16a/0x200 fs/hfs/bnode.c:35 hfs_bnode_read_key+0x174/0x240 fs/hfs/bnode.c:70 hfs_brec_insert+0x7f7/0xbe0 fs/hfs/brec.c:159 hfs_cat_create+0x3de/0x760 fs/hfs/catalog.c:118 hfs_mkdir+0x6c/0xe0 fs/hfs/dir.c:232 vfs_mkdir+0x2f9/0x500 fs/namei.c:4324 do_mkdirat+0x273/0x3f0 fs/namei.c:4357 __do_sys_mkdirat fs/namei.c:4374 [inline] __se_sys_mkdirat fs/namei.c:4372 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4372 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fdd8098b9d7 Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 02 01 00 00 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:00007fdd817ece68 EFLAGS: 00000246 ORIG_RAX: 0000000000000102 RAX: ffffffffffffffda RBX: 00007fdd817ecef0 RCX: 00007fdd8098b9d7 RDX: 00000000000001ff RSI: 0000200000000100 RDI: 00000000ffffff9c RBP: 0000000000000000 R08: 0000200000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000200000000100 R13: 00007fdd817eceb0 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 6580: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x9d/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4331 [inline] __kmalloc_noprof+0x28e/0x4d0 mm/slub.c:4343 kmalloc_noprof include/linux/slab.h:909 [inline] hfs_find_init+0x92/0x1f0 fs/hfs/bfind.c:21 hfs_cat_create+0x181/0x760 fs/hfs/catalog.c:96 hfs_mkdir+0x6c/0xe0 fs/hfs/dir.c:232 vfs_mkdir+0x2f9/0x500 fs/namei.c:4324 do_mkdirat+0x273/0x3f0 fs/namei.c:4357 __do_sys_mkdirat fs/namei.c:4374 [inline] __se_sys_mkdirat fs/namei.c:4372 [inline] __x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4372 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888025a0ec80 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 0 bytes inside of allocated 78-byte region [ffff888025a0ec80, ffff888025a0ecce) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff888025a0ef00 pfn:0x25a0e ksm flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88801b041280 ffffea0000a5c1c0 dead000000000003 raw: ffff888025a0ef00 000000008020001f 00000000f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 1, tgid 1 (swapper/0), ts 9569496827, free_ts 0 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1717 prep_new_page mm/page_alloc.c:1725 [inline] get_page_from_freelist+0x351d/0x36b0 mm/page_alloc.c:3652 __alloc_frozen_pages_noprof+0x211/0x5b0 mm/page_alloc.c:4934 alloc_pages_mpol+0x339/0x690 mm/mempolicy.c:2301 alloc_slab_page mm/slub.c:2459 [inline] allocate_slab+0x8f/0x3a0 mm/slub.c:2623 new_slab mm/slub.c:2676 [inline] ___slab_alloc+0xc3b/0x1500 mm/slub.c:3862 __slab_alloc+0x58/0xa0 mm/slub.c:3952 __slab_alloc_node mm/slub.c:4027 [inline] slab_alloc_node mm/slub.c:4188 [inline] __kmalloc_cache_noprof+0x26a/0x370 mm/slub.c:4357 kmalloc_noprof include/linux/slab.h:905 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] blk_mq_alloc_ctxs block/blk-mq.c:4284 [inline] blk_mq_init_allocated_queue+0x122/0x14d0 block/blk-mq.c:4538 blk_mq_alloc_queue block/blk-mq.c:4352 [inline] __blk_mq_alloc_disk+0x1b0/0x380 block/blk-mq.c:4395 loop_add+0x445/0xaf0 drivers/block/loop.c:2067 loop_init+0x168/0x220 drivers/block/loop.c:2302 do_one_initcall+0x24a/0x940 init/main.c:1257 do_initcall_level+0x157/0x210 init/main.c:1319 do_initcalls+0x71/0xd0 init/main.c:1335 kernel_init_freeable+0x432/0x5d0 init/main.c:1567 page_owner free stack trace missing Memory state around the buggy address: ffff888025a0eb80: 00 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc ffff888025a0ec00: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc >ffff888025a0ec80: 00 00 00 00 00 00 00 00 00 06 fc fc fc fc fc fc ^ ffff888025a0ed00: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc ffff888025a0ed80: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ==================================================================