syz.6.342: attempt to access beyond end of device loop6: rw=524288, sector=720, nr_sectors = 8 limit=16 ================================================================== BUG: KASAN: use-after-free in z_erofs_transform_plain+0x3a4/0x4ac fs/erofs/decompressor.c:350 Read of size 4095 at addr ffff0000d1c2b400 by task syz.6.342/6604 CPU: 1 PID: 6604 Comm: syz.6.342 Not tainted 6.1.129-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call trace: dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0x174/0x4c0 mm/kasan/report.c:427 kasan_report+0xd4/0x130 mm/kasan/report.c:531 kasan_check_range+0x264/0x2a4 mm/kasan/generic.c:189 memcpy+0x48/0x90 mm/kasan/shadow.c:65 z_erofs_transform_plain+0x3a4/0x4ac fs/erofs/decompressor.c:350 z_erofs_decompress+0x9c/0xd4 fs/erofs/decompressor.c:439 z_erofs_decompress_pcluster fs/erofs/zdata.c:1175 [inline] z_erofs_decompress_queue+0x13b0/0x2388 fs/erofs/zdata.c:1258 z_erofs_runqueue+0x166c/0x18b4 fs/erofs/zdata.c:1616 z_erofs_readahead+0x988/0xe04 fs/erofs/zdata.c:1760 read_pages+0x168/0x6a0 mm/readahead.c:161 page_cache_ra_unbounded+0x46c/0x58c 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+0x3f8/0x648 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+0x98/0x2bc arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204 el0_svc+0x58/0x168 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:000000004d82386f refcount:2 mapcount:0 mapping:000000007cc066d5 index:0x1 pfn:0x111c2b memcg:ffff0000fa8e0000 aops:managed_cache_aops ino:0 flags: 0x5ffd00000002014(uptodate|lru|private|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffd00000002014 fffffc0003a7f808 fffffc0003795088 ffff0000fac807c8 raw: 0000000000000001 ffff0000e10a9000 00000002ffffffff ffff0000fa8e0000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000d1c2bf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff0000d1c2bf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff0000d1c2c000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff0000d1c2c080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff0000d1c2c100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ==================================================================