netlink: 4 bytes leftover after parsing attributes in process `syz.2.110'. ================================================================== BUG: KASAN: slab-out-of-bounds in memcpy_from_page include/linux/highmem.h:423 [inline] BUG: KASAN: slab-out-of-bounds in hfs_bnode_read+0x167/0x200 fs/hfs/bnode.c:35 Write of size 94 at addr ffff8880341b9200 by task syz.2.110/6561 CPU: 1 UID: 0 PID: 6561 Comm: syz.2.110 Not tainted 6.14.0-rc3-next-20250218-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:410 [inline] print_report+0x16b/0x5a0 mm/kasan/report.c:510 kasan_report+0x143/0x180 mm/kasan/report.c:623 kasan_check_range+0x282/0x290 mm/kasan/generic.c:189 __asan_memcpy+0x40/0x70 mm/kasan/shadow.c:106 memcpy_from_page include/linux/highmem.h:423 [inline] hfs_bnode_read+0x167/0x200 fs/hfs/bnode.c:35 hfs_bnode_read_key+0x172/0x240 fs/hfs/bnode.c:70 hfs_brec_insert+0x7f3/0xbd0 fs/hfs/brec.c:159 hfs_cat_create+0x3dc/0x760 fs/hfs/catalog.c:118 hfs_create+0x66/0xe0 fs/hfs/dir.c:202 lookup_open fs/namei.c:3659 [inline] open_last_lookups fs/namei.c:3758 [inline] path_openat+0x1954/0x35b0 fs/namei.c:3994 do_filp_open+0x282/0x4e0 fs/namei.c:4024 do_sys_openat2+0x13f/0x1c0 fs/open.c:1428 do_sys_open fs/open.c:1443 [inline] __do_sys_openat fs/open.c:1459 [inline] __se_sys_openat fs/open.c:1454 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1454 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fe31478d169 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fe31560d038 EFLAGS: 00000246 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007fe3149a5fa0 RCX: 00007fe31478d169 RDX: 000000000000275a RSI: 0000400000000300 RDI: ffffffffffffff9c RBP: 00007fe31480e2a0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fe3149a5fa0 R15: 00007ffc334c96c8 Allocated by task 6561: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __do_kmalloc_node mm/slub.c:4308 [inline] __kmalloc_noprof+0x285/0x4c0 mm/slub.c:4320 kmalloc_noprof include/linux/slab.h:915 [inline] hfs_find_init+0x90/0x1f0 fs/hfs/bfind.c:21 hfs_cat_create+0x17f/0x760 fs/hfs/catalog.c:96 hfs_create+0x66/0xe0 fs/hfs/dir.c:202 lookup_open fs/namei.c:3659 [inline] open_last_lookups fs/namei.c:3758 [inline] path_openat+0x1954/0x35b0 fs/namei.c:3994 do_filp_open+0x282/0x4e0 fs/namei.c:4024 do_sys_openat2+0x13f/0x1c0 fs/open.c:1428 do_sys_open fs/open.c:1443 [inline] __do_sys_openat fs/open.c:1459 [inline] __se_sys_openat fs/open.c:1454 [inline] __x64_sys_openat+0x247/0x2a0 fs/open.c:1454 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880341b9200 which belongs to the cache kmalloc-96 of size 96 The buggy address is located 0 bytes inside of allocated 78-byte region [ffff8880341b9200, ffff8880341b924e) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x341b9 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88801b041280 ffffea00009e7c40 dead000000000004 raw: 0000000000000000 0000000080200020 00000000f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 976, tgid 976 (kworker/0:2), ts 90288004584, free_ts 90139922379 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f4/0x240 mm/page_alloc.c:1629 prep_new_page mm/page_alloc.c:1637 [inline] get_page_from_freelist+0x365c/0x37a0 mm/page_alloc.c:3555 __alloc_frozen_pages_noprof+0x292/0x710 mm/page_alloc.c:4817 alloc_pages_mpol+0x311/0x660 mm/mempolicy.c:2301 alloc_slab_page mm/slub.c:2437 [inline] allocate_slab+0x8f/0x3a0 mm/slub.c:2601 new_slab mm/slub.c:2654 [inline] ___slab_alloc+0xc27/0x14a0 mm/slub.c:3840 __slab_alloc+0x58/0xa0 mm/slub.c:3930 __slab_alloc_node mm/slub.c:4005 [inline] slab_alloc_node mm/slub.c:4166 [inline] __kmalloc_cache_noprof+0x27b/0x390 mm/slub.c:4334 kmalloc_noprof include/linux/slab.h:911 [inline] dst_cow_metrics_generic+0x56/0x1c0 net/core/dst.c:185 dst_metrics_write_ptr include/net/dst.h:133 [inline] dst_metric_set include/net/dst.h:194 [inline] icmp6_dst_alloc+0x270/0x420 net/ipv6/route.c:3293 mld_sendpack+0x6a3/0xdb0 net/ipv6/mcast.c:1857 mld_send_cr net/ipv6/mcast.c:2169 [inline] mld_ifc_work+0x7d9/0xd90 net/ipv6/mcast.c:2702 process_one_work kernel/workqueue.c:3238 [inline] process_scheduled_works+0xabe/0x18e0 kernel/workqueue.c:3319 worker_thread+0x870/0xd30 kernel/workqueue.c:3400 kthread+0x7a9/0x920 kernel/kthread.c:464 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 page last free pid 5827 tgid 5827 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1205 [inline] free_frozen_pages+0xe0d/0x10e0 mm/page_alloc.c:2738 discard_slab mm/slub.c:2698 [inline] __put_partials+0x160/0x1c0 mm/slub.c:3167 put_cpu_partial+0x17c/0x250 mm/slub.c:3242 __slab_free+0x290/0x380 mm/slub.c:4493 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x14f/0x170 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x23/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4129 [inline] slab_alloc_node mm/slub.c:4178 [inline] kmem_cache_alloc_node_noprof+0x1d9/0x380 mm/slub.c:4230 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:668 alloc_skb include/linux/skbuff.h:1331 [inline] nlmsg_new include/net/netlink.h:1018 [inline] rtmsg_ifa+0x1f0/0x3b0 net/ipv4/devinet.c:2015 __inet_insert_ifa+0xa54/0xc90 net/ipv4/devinet.c:566 inet_rtm_newaddr+0x1220/0x1bc0 net/ipv4/devinet.c:1002 rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6917 netlink_rcv_skb+0x206/0x480 net/netlink/af_netlink.c:2543 netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline] netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1348 netlink_sendmsg+0x8b3/0xca0 net/netlink/af_netlink.c:1892 Memory state around the buggy address: ffff8880341b9100: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff8880341b9180: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc >ffff8880341b9200: 00 00 00 00 00 00 00 00 00 06 fc fc fc fc fc fc ^ ffff8880341b9280: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff8880341b9300: fa fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ==================================================================