loop7: rw=524288, sector=34359738360, nr_sectors = 8 limit=16 syz.7.2995: attempt to access beyond end of device loop7: rw=524288, sector=8, nr_sectors = 16 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+0x39c/0x494 fs/erofs/decompressor.c:347 Read of size 4096 at addr ffff0000f2ee0000 by task syz.7.2995/12681 CPU: 1 PID: 12681 Comm: syz.7.2995 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:1161 [inline] z_erofs_decompress_queue+0x103c/0x1bf4 fs/erofs/zdata.c:1242 z_erofs_runqueue+0x1508/0x16a8 fs/erofs/zdata.c:1614 z_erofs_read_folio+0x2dc/0x5cc fs/erofs/zdata.c:1704 filemap_read_folio+0x134/0x384 mm/filemap.c:2490 filemap_update_page mm/filemap.c:2575 [inline] filemap_get_pages mm/filemap.c:2689 [inline] filemap_read+0x1290/0x20dc mm/filemap.c:2759 generic_file_read_iter+0xf8/0x5ac mm/filemap.c:2941 call_read_iter include/linux/fs.h:2265 [inline] new_sync_read fs/read_write.c:389 [inline] vfs_read+0x3cc/0x7b8 fs/read_write.c:470 ksys_read+0x12c/0x228 fs/read_write.c:613 __do_sys_read fs/read_write.c:623 [inline] __se_sys_read fs/read_write.c:621 [inline] __arm64_sys_read+0x7c/0x90 fs/read_write.c:621 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x290 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x200/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x12c 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:589 The buggy address belongs to the physical page: page:00000000d2f6f8f1 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x132ee0 flags: 0x5ffc00000000000(node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000000000 fffffc00031c6908 fffffc0003cbb888 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000f2edff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff0000f2edff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff0000f2ee0000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff0000f2ee0080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff0000f2ee0100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ================================================================== syz.7.2995: attempt to access beyond end of device loop7: rw=0, sector=34359738360, nr_sectors = 8 limit=16