syz.3.810: attempt to access beyond end of device loop3: rw=524288, sector=16, nr_sectors = 40 limit=16 ================================================================== BUG: KASAN: use-after-free in memcpy_to_page include/linux/highmem.h:403 [inline] BUG: KASAN: use-after-free in z_erofs_transform_plain+0x388/0x460 fs/erofs/decompressor.c:346 Read of size 4096 at addr ffff88805d7f7000 by task syz.3.810/7029 CPU: 1 PID: 7029 Comm: syz.3.810 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x210 mm/kasan/report.c:420 kasan_report+0x10b/0x140 mm/kasan/report.c:524 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x235/0x290 mm/kasan/generic.c:189 memcpy+0x25/0x60 mm/kasan/shadow.c:65 memcpy_to_page include/linux/highmem.h:403 [inline] z_erofs_transform_plain+0x388/0x460 fs/erofs/decompressor.c:346 z_erofs_decompress_pcluster fs/erofs/zdata.c:1159 [inline] z_erofs_decompress_queue+0x170d/0x2540 fs/erofs/zdata.c:1240 z_erofs_runqueue+0x1a48/0x1be0 fs/erofs/zdata.c:1603 z_erofs_read_folio+0x367/0x630 fs/erofs/zdata.c:1693 filemap_read_folio+0x16b/0x770 mm/filemap.c:2490 filemap_update_page mm/filemap.c:2575 [inline] filemap_get_pages mm/filemap.c:2689 [inline] filemap_read+0x1850/0x3020 mm/filemap.c:2759 generic_file_read_iter+0x136/0x740 mm/filemap.c:2941 __kernel_read+0x2ec/0x6d0 fs/read_write.c:428 integrity_kernel_read+0x86/0xd0 security/integrity/iint.c:228 ima_calc_file_hash_tfm security/integrity/ima/ima_crypto.c:485 [inline] ima_calc_file_shash security/integrity/ima/ima_crypto.c:516 [inline] ima_calc_file_hash+0x910/0x1900 security/integrity/ima/ima_crypto.c:573 ima_collect_measurement+0x503/0xb50 security/integrity/ima/ima_api.c:293 process_measurement+0x1183/0x1c30 security/integrity/ima/ima_main.c:351 ima_file_check+0xc8/0x110 security/integrity/ima/ima_main.c:534 do_open fs/namei.c:3636 [inline] path_openat+0x26e8/0x2ee0 fs/namei.c:3791 do_filp_open+0x1f1/0x430 fs/namei.c:3818 do_sys_openat2+0x150/0x4b0 fs/open.c:1320 do_sys_open fs/open.c:1336 [inline] __do_sys_openat fs/open.c:1352 [inline] __se_sys_openat fs/open.c:1347 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1347 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f4fc1f9c819 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f4fc2dbc028 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f4fc2215fa0 RCX: 00007f4fc1f9c819 RDX: 0000000000080000 RSI: 0000200000000100 RDI: ffffffffffffff9c RBP: 00007f4fc2032c91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f4fc2216038 R14: 00007f4fc2215fa0 R15: 00007ffd935c6a38 Allocated by task 7032: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 __kasan_slab_alloc+0x6b/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x480 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+0x123/0x2f0 mm/slub.c:3383 anon_vma_chain_alloc mm/rmap.c:141 [inline] __anon_vma_prepare+0x64/0x420 mm/rmap.c:195 anon_vma_prepare include/linux/rmap.h:159 [inline] do_cow_fault mm/memory.c:4645 [inline] do_fault mm/memory.c:4760 [inline] handle_pte_fault mm/memory.c:5029 [inline] __handle_mm_fault mm/memory.c:5171 [inline] handle_mm_fault+0x3691/0x3ee0 mm/memory.c:5292 do_user_addr_fault+0x51f/0xb10 arch/x86/mm/fault.c:1338 handle_page_fault arch/x86/mm/fault.c:1429 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 Freed by task 7032: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1729 [inline] slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1755 slab_free mm/slub.c:3687 [inline] kmem_cache_free+0xf7/0x290 mm/slub.c:3709 anon_vma_chain_free mm/rmap.c:146 [inline] unlink_anon_vmas+0x2c8/0x660 mm/rmap.c:420 free_pgtables+0x263/0x400 mm/memory.c:430 exit_mmap+0x37c/0x960 mm/mmap.c:3260 __mmput+0x118/0x3c0 kernel/fork.c:1205 exit_mm+0x1fe/0x2d0 kernel/exit.c:565 do_exit+0x905/0x2480 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:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88805d7f7000 which belongs to the cache anon_vma_chain of size 80 The buggy address is located 0 bytes inside of 80-byte region [ffff88805d7f7000, ffff88805d7f7050) The buggy address belongs to the physical page: page:ffffea000175fdc0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5d7f7 memcg:ffff888070efd801 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 0000000000000000 dead000000000122 ffff888140008280 raw: 0000000000000000 0000000000240024 00000001ffffffff ffff888070efd801 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 7032, tgid 7032 (sed), ts 195877002627, free_ts 195811919164 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2559 prep_new_page mm/page_alloc.c:2566 [inline] get_page_from_freelist+0x1a1e/0x1ab0 mm/page_alloc.c:4357 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5657 alloc_slab_page+0x5d/0x160 mm/slub.c:1799 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2c0 mm/slub.c:1997 ___slab_alloc+0xbc6/0x1240 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc+0x1b7/0x2f0 mm/slub.c:3383 anon_vma_chain_alloc mm/rmap.c:141 [inline] __anon_vma_prepare+0x64/0x420 mm/rmap.c:195 anon_vma_prepare include/linux/rmap.h:159 [inline] do_cow_fault mm/memory.c:4645 [inline] do_fault mm/memory.c:4760 [inline] handle_pte_fault mm/memory.c:5029 [inline] __handle_mm_fault mm/memory.c:5171 [inline] handle_mm_fault+0x3691/0x3ee0 mm/memory.c:5292 do_user_addr_fault+0x51f/0xb10 arch/x86/mm/fault.c:1338 handle_page_fault arch/x86/mm/fault.c:1429 [inline] exc_page_fault+0x60/0x100 arch/x86/mm/fault.c:1482 asm_exc_page_fault+0x22/0x30 arch/x86/include/asm/idtentry.h:608 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1486 [inline] free_pcp_prepare mm/page_alloc.c:1536 [inline] free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3413 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3508 free_slab mm/slub.c:2036 [inline] discard_slab mm/slub.c:2042 [inline] __unfreeze_partials+0x1a5/0x200 mm/slub.c:2591 put_cpu_partial+0x17c/0x250 mm/slub.c:2667 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x480 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+0x123/0x2f0 mm/slub.c:3383 getname_flags+0xb7/0x500 fs/namei.c:139 do_sys_openat2+0xdd/0x4b0 fs/open.c:1314 do_sys_open fs/open.c:1336 [inline] __do_sys_openat fs/open.c:1352 [inline] __se_sys_openat fs/open.c:1347 [inline] __x64_sys_openat+0x135/0x160 fs/open.c:1347 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff88805d7f6f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88805d7f6f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88805d7f7000: fa fb fb fb fb fb fb fb fb fb fc fc fc fc fa fb ^ ffff88805d7f7080: fb fb fb fb fb fb fb fb fc fc fc fc fa fb fb fb ffff88805d7f7100: fb fb fb fb fb fb fc fc fc fc fa fb fb fb fb fb 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