================================================================== BUG: KASAN: use-after-free in z_erofs_transform_plain+0x394/0x4a0 fs/erofs/decompressor.c:350 Read of size 1622 at addr ffff88802406fe5b by task syz.3.325/5551 CPU: 0 PID: 5551 Comm: syz.3.325 Not tainted 6.1.134-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0x15f/0x4f0 mm/kasan/report.c:427 kasan_report+0x136/0x160 mm/kasan/report.c:531 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x27f/0x290 mm/kasan/generic.c:189 memcpy+0x25/0x60 mm/kasan/shadow.c:65 z_erofs_transform_plain+0x394/0x4a0 fs/erofs/decompressor.c:350 z_erofs_decompress_pcluster fs/erofs/zdata.c:1175 [inline] z_erofs_decompress_queue+0x1aad/0x2d80 fs/erofs/zdata.c:1258 z_erofs_runqueue+0x1bfe/0x1e10 fs/erofs/zdata.c:1616 z_erofs_readahead+0xc26/0x1030 fs/erofs/zdata.c:1760 read_pages+0x17f/0x830 mm/readahead.c:161 page_cache_ra_unbounded+0x68b/0x7b0 mm/readahead.c:270 do_page_cache_ra mm/readahead.c:300 [inline] force_page_cache_ra+0x2a3/0x300 mm/readahead.c:331 force_page_cache_readahead mm/internal.h:125 [inline] generic_fadvise+0x553/0x7b0 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+0x138/0x180 mm/fadvise.c:212 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f4a09d8d169 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:00007f4a0ab8a038 EFLAGS: 00000246 ORIG_RAX: 00000000000000dd RAX: ffffffffffffffda RBX: 00007f4a09fa6080 RCX: 00007f4a09d8d169 RDX: 0000000000000000 RSI: 000000000000fcff RDI: 0000000000000004 RBP: 00007f4a09e0e990 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f4a09fa6080 R15: 00007fff95d2bf58 The buggy address belongs to the physical page: page:ffffea0000901bc0 refcount:2 mapcount:0 mapping:ffff8880535b2d30 index:0x1 pfn:0x2406f memcg:ffff88814dbe4000 aops:managed_cache_aops ino:0 flags: 0xfff40000002014(uptodate|lru|private|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff40000002014 ffffea0001447948 ffffea0000a546c8 ffff8880535b2d30 raw: 0000000000000001 ffff88805348ec30 00000002ffffffff ffff88814dbe4000 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 5533, tgid 5532 (syz.3.325), ts 192534263611, free_ts 174871832606 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2532 prep_new_page mm/page_alloc.c:2539 [inline] get_page_from_freelist+0x3731/0x38d0 mm/page_alloc.c:4328 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5606 z_erofs_bind_cache fs/erofs/zdata.c:482 [inline] z_erofs_do_read_page+0x19df/0x3ce0 fs/erofs/zdata.c:860 z_erofs_read_folio+0x31a/0x760 fs/erofs/zdata.c:1705 filemap_read_folio+0x199/0x780 mm/filemap.c:2489 do_read_cache_folio+0x2ee/0x810 mm/filemap.c:3626 erofs_bread+0x19d/0x6b0 fs/erofs/data.c:50 erofs_find_target_block fs/erofs/namei.c:102 [inline] erofs_namei+0x278/0xef0 fs/erofs/namei.c:175 erofs_lookup+0x1d6/0x4d0 fs/erofs/namei.c:204 lookup_one_qstr_excl+0x117/0x240 fs/namei.c:1605 filename_create+0x293/0x530 fs/namei.c:3877 do_mkdirat+0xba/0x360 fs/namei.c:4121 __do_sys_mkdirat fs/namei.c:4146 [inline] __se_sys_mkdirat fs/namei.c:4144 [inline] __x64_sys_mkdirat+0x85/0x90 fs/namei.c:4144 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 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+0x12a6/0x15b0 mm/page_alloc.c:3384 free_unref_page+0x33/0x3e0 mm/page_alloc.c:3479 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x156/0x170 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737 slab_alloc_node mm/slub.c:3398 [inline] __kmem_cache_alloc_node+0x137/0x260 mm/slub.c:3437 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc+0xa1/0x230 mm/slab_common.c:949 kmalloc include/linux/slab.h:568 [inline] kzalloc include/linux/slab.h:699 [inline] tomoyo_encode2 security/tomoyo/realpath.c:45 [inline] tomoyo_encode+0x26b/0x530 security/tomoyo/realpath.c:80 tomoyo_path_perm+0x3b6/0x710 security/tomoyo/file.c:831 tomoyo_path_symlink+0xda/0x110 security/tomoyo/tomoyo.c:199 security_path_symlink+0xd9/0x130 security/security.c:1198 do_symlinkat+0x132/0x390 fs/namei.c:4495 __do_sys_symlinkat fs/namei.c:4517 [inline] __se_sys_symlinkat fs/namei.c:4514 [inline] __x64_sys_symlinkat+0x95/0xa0 fs/namei.c:4514 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff88802406ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88802406ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888024070000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888024070080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888024070100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================