syz.3.17: attempt to access beyond end of device loop3: rw=524288, sector=16, nr_sectors = 8 limit=16 syz.3.17: attempt to access beyond end of device loop3: rw=524288, sector=13716630376, nr_sectors = 8 limit=16 ================================================================== BUG: KASAN: use-after-free in z_erofs_transform_plain+0x37a/0x490 fs/erofs/decompressor.c:350 Read of size 4095 at addr ffff888024ae6400 by task syz.3.17/4443 CPU: 1 PID: 4443 Comm: syz.3.17 Not tainted 6.1.146-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x200 mm/kasan/report.c:418 kasan_report+0x10b/0x140 mm/kasan/report.c:522 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x27b/0x290 mm/kasan/generic.c:189 memcpy+0x25/0x60 mm/kasan/shadow.c:65 z_erofs_transform_plain+0x37a/0x490 fs/erofs/decompressor.c:350 z_erofs_decompress_pcluster fs/erofs/zdata.c:1167 [inline] z_erofs_decompress_queue+0x1577/0x2370 fs/erofs/zdata.c:1250 z_erofs_runqueue+0x19a9/0x1af0 fs/erofs/zdata.c:1607 z_erofs_readahead+0xa3b/0xda0 fs/erofs/zdata.c:1743 read_pages+0x173/0x840 mm/readahead.c:161 page_cache_ra_unbounded+0x690/0x770 mm/readahead.c:270 do_page_cache_ra mm/readahead.c:300 [inline] force_page_cache_ra+0x2bd/0x320 mm/readahead.c:331 force_page_cache_readahead mm/internal.h:125 [inline] generic_fadvise+0x44e/0x6c0 mm/fadvise.c:107 vfs_fadvise mm/fadvise.c:185 [inline] ksys_fadvise64_64 mm/fadvise.c:199 [inline] __do_sys_fadvise64 mm/fadvise.c:214 [inline] __se_sys_fadvise64 mm/fadvise.c:212 [inline] __x64_sys_fadvise64+0x139/0x180 mm/fadvise.c:212 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fdb6b78e9a9 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:00007fdb6c62b038 EFLAGS: 00000246 ORIG_RAX: 00000000000000dd RAX: ffffffffffffffda RBX: 00007fdb6b9b5fa0 RCX: 00007fdb6b78e9a9 RDX: 000000000000ff39 RSI: 000000000000aa17 RDI: 0000000000000004 RBP: 00007fdb6b810d69 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fdb6b9b5fa0 R15: 00007ffea3dc2a38 The buggy address belongs to the physical page: page:ffffea000092b980 refcount:2 mapcount:0 mapping:ffff888053e507c8 index:0x1 pfn:0x24ae6 memcg:ffff88807c2e6000 aops:managed_cache_aops ino:0 flags: 0xfff40000002014(uptodate|lru|private|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff40000002014 ffffea00006eef08 ffffea0001a17908 ffff888053e507c8 raw: 0000000000000001 ffff888053e2e000 00000002ffffffff ffff88807c2e6000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x192840(GFP_NOWAIT|__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4443, tgid 4442 (syz.3.17), ts 91202717126, free_ts 90931344488 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2532 prep_new_page mm/page_alloc.c:2539 [inline] get_page_from_freelist+0x1a26/0x1ac0 mm/page_alloc.c:4328 __alloc_pages+0x1df/0x4e0 mm/page_alloc.c:5614 z_erofs_bind_cache fs/erofs/zdata.c:486 [inline] z_erofs_do_read_page+0x1be1/0x3c70 fs/erofs/zdata.c:863 z_erofs_read_folio+0x246/0x5b0 fs/erofs/zdata.c:1692 filemap_read_folio+0x160/0x760 mm/filemap.c:2490 do_read_cache_folio+0x2a0/0x760 mm/filemap.c:3627 erofs_bread+0x18e/0x670 fs/erofs/data.c:50 erofs_find_target_block fs/erofs/namei.c:102 [inline] erofs_namei+0x28f/0xf00 fs/erofs/namei.c:175 erofs_lookup+0x14b/0x390 fs/erofs/namei.c:204 lookup_open fs/namei.c:3460 [inline] open_last_lookups fs/namei.c:3550 [inline] path_openat+0xfaf/0x2e70 fs/namei.c:3780 do_filp_open+0x1c1/0x3c0 fs/namei.c:3810 do_sys_openat2+0x142/0x490 fs/open.c:1318 do_sys_open fs/open.c:1334 [inline] __do_sys_creat fs/open.c:1412 [inline] __se_sys_creat fs/open.c:1406 [inline] __x64_sys_creat+0x8c/0xb0 fs/open.c:1406 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1459 [inline] free_pcp_prepare mm/page_alloc.c:1509 [inline] free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384 free_unref_page_list+0xbb/0x8e0 mm/page_alloc.c:3525 release_pages+0x1f92/0x2200 mm/swap.c:1035 tlb_batch_pages_flush mm/mmu_gather.c:59 [inline] tlb_flush_mmu_free mm/mmu_gather.c:254 [inline] tlb_flush_mmu+0xff/0x210 mm/mmu_gather.c:261 tlb_finish_mmu+0xbd/0x1c0 mm/mmu_gather.c:361 exit_mmap+0x343/0x8e0 mm/mmap.c:3258 __mmput+0x118/0x3c0 kernel/fork.c:1200 exit_mm+0x1e6/0x2c0 kernel/exit.c:565 do_exit+0x8c1/0x2400 kernel/exit.c:867 do_group_exit+0x217/0x2d0 kernel/exit.c:1022 __do_sys_exit_group kernel/exit.c:1033 [inline] __se_sys_exit_group kernel/exit.c:1031 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:1031 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff888024ae6f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888024ae6f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888024ae7000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888024ae7080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888024ae7100: fb fb fc fc fc fc fc fc fc fc fa fb fb fb fb fb ==================================================================