loop0: rw=524288, sector=16, nr_sectors = 16 limit=16 syz.0.17: attempt to access beyond end of device loop0: rw=524288, sector=14425508768, nr_sectors = 8 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+0x3a4/0x490 fs/erofs/decompressor.c:346 Read of size 1622 at addr ffff0000d2a67e5b by task syz.0.17/4455 CPU: 1 PID: 4455 Comm: syz.0.17 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call trace: dump_backtrace+0x1c0/0x1ec 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+0x3a4/0x490 fs/erofs/decompressor.c:346 z_erofs_decompress+0x9c/0xd4 fs/erofs/decompressor.c:434 z_erofs_decompress_pcluster fs/erofs/zdata.c:1159 [inline] z_erofs_decompress_queue+0x100c/0x1b40 fs/erofs/zdata.c:1240 z_erofs_runqueue+0x152c/0x16cc fs/erofs/zdata.c:1603 z_erofs_readahead+0x84c/0xbf4 fs/erofs/zdata.c:1739 read_pages+0x158/0x680 mm/readahead.c:161 page_cache_ra_unbounded+0x490/0x574 mm/readahead.c:270 do_page_cache_ra mm/readahead.c:300 [inline] force_page_cache_ra+0x248/0x2b0 mm/readahead.c:331 force_page_cache_readahead mm/internal.h:125 [inline] generic_fadvise+0x340/0x5b8 mm/fadvise.c:107 vfs_fadvise mm/fadvise.c:185 [inline] ksys_fadvise64_64 mm/fadvise.c:199 [inline] __do_sys_fadvise64_64 mm/fadvise.c:207 [inline] __se_sys_fadvise64_64 mm/fadvise.c:205 [inline] __arm64_sys_fadvise64_64+0x12c/0x174 mm/fadvise.c:205 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b4 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x130 arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x128 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:585 The buggy address belongs to the physical page: page:0000000032c728ad refcount:2 mapcount:0 mapping:0000000044d71d02 index:0x1 pfn:0x112a67 memcg:ffff0000da914000 aops:managed_cache_aops ino:0 flags: 0x5ffd00000002014(uptodate|lru|private|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffd00000002014 fffffc0003791948 fffffc0003791e88 ffff0000e57f07c8 raw: 0000000000000001 ffff0000e2494000 00000002ffffffff ffff0000da914000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000d2a67f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff0000d2a67f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff0000d2a68000: fa fb fb fb fb fb fb fb fb fb fc fc fc fc fa fb ^ ffff0000d2a68080: fb fb fb fb fb fb fb fb fc fc fc fc fa fb fb fb ffff0000d2a68100: fb fb fb fb fb fb fc fc fc fc fa fb fb fb fb fb ==================================================================