loop9: rw=524288, sector=34359738360, nr_sectors = 8 limit=16 syz.9.71: attempt to access beyond end of device loop9: 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 ffff0000e9b9c000 by task syz.9.71/4996 CPU: 1 PID: 4996 Comm: syz.9.71 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/02/2026 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:1159 [inline] z_erofs_decompress_queue+0x103c/0x1bf4 fs/erofs/zdata.c:1240 z_erofs_runqueue+0x1508/0x16a8 fs/erofs/zdata.c:1603 z_erofs_read_folio+0x2dc/0x5cc fs/erofs/zdata.c:1693 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:2259 [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+0x13c/0x258 arch/arm64/kernel/syscall.c:140 do_el0_svc+0x5c/0x134 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 Allocated by task 4380: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:53 kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:505 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0xa0/0xb8 mm/kasan/common.c:384 kasan_kmalloc include/linux/kasan.h:211 [inline] kmalloc_trace+0x7c/0x94 mm/slab_common.c:1031 kmalloc include/linux/slab.h:563 [inline] dst_cow_metrics_generic+0x60/0x220 net/core/dst.c:202 dst_metrics_write_ptr include/net/dst.h:119 [inline] dst_metric_set include/net/dst.h:180 [inline] icmp6_dst_alloc+0x26c/0x3fc net/ipv6/route.c:3325 mld_sendpack+0x780/0x112c net/ipv6/mcast.c:1842 mld_send_initial_cr+0x238/0x2fc net/ipv6/mcast.c:2271 ipv6_mc_dad_complete+0x74/0x170 net/ipv6/mcast.c:2279 addrconf_dad_completed+0x600/0xb3c net/ipv6/addrconf.c:4283 addrconf_dad_work+0x904/0x10a0 net/ipv6/addrconf.c:-1 process_one_work+0x7e4/0x13bc kernel/workqueue.c:2292 worker_thread+0x8cc/0xfe8 kernel/workqueue.c:2439 kthread+0x254/0x2e0 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:850 Freed by task 15: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4c/0x80 mm/kasan/common.c:53 kasan_save_free_info+0x38/0x5c mm/kasan/generic.c:516 ____kasan_slab_free+0x148/0x1b0 mm/kasan/common.c:237 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:245 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1729 [inline] slab_free_freelist_hook+0x16c/0x1e8 mm/slub.c:1755 slab_free mm/slub.c:3687 [inline] __kmem_cache_free+0xbc/0x21c mm/slub.c:3700 kfree+0xd0/0x1a8 mm/slab_common.c:988 ip_dst_metrics_put include/net/ip.h:527 [inline] ip6_dst_destroy+0xb4/0x3d8 net/ipv6/route.c:363 dst_destroy+0xc4/0x314 net/core/dst.c:112 dst_destroy_rcu+0x20/0x30 net/core/dst.c:133 rcu_do_batch kernel/rcu/tree.c:2297 [inline] rcu_core+0x848/0x18e8 kernel/rcu/tree.c:2557 rcu_core_si+0x10/0x1c kernel/rcu/tree.c:2574 handle_softirqs+0x318/0xc90 kernel/softirq.c:596 run_ksoftirqd+0x7c/0x2ac kernel/softirq.c:968 smpboot_thread_fn+0x4e8/0x960 kernel/smpboot.c:164 kthread+0x254/0x2e0 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:850 The buggy address belongs to the object at ffff0000e9b9c000 which belongs to the cache kmalloc-128 of size 128 The buggy address is located 0 bytes inside of 128-byte region [ffff0000e9b9c000, ffff0000e9b9c080) The buggy address belongs to the physical page: page:00000000c7fbedaf refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x129b9c flags: 0x5ffc00000000200(slab|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000000200 dead000000000100 dead000000000122 ffff0000c0002300 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000e9b9bf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff0000e9b9bf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff0000e9b9c000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000e9b9c080: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff0000e9b9c100: 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc fc ================================================================== syz.9.71: attempt to access beyond end of device loop9: rw=0, sector=34359738360, nr_sectors = 8 limit=16