================================================================== BUG: KASAN: slab-out-of-bounds in fib6_add_rt2node net/ipv6/ip6_fib.c:1140 [inline] BUG: KASAN: slab-out-of-bounds in fib6_add+0x4680/0x46e0 net/ipv6/ip6_fib.c:1503 Read of size 1 at addr ffff8880626090ce by task syz.7.5972/26556 CPU: 0 PID: 26556 Comm: syz.7.5972 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xa8/0x210 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 fib6_add_rt2node net/ipv6/ip6_fib.c:1140 [inline] fib6_add+0x4680/0x46e0 net/ipv6/ip6_fib.c:1503 __ip6_ins_rt net/ipv6/route.c:1352 [inline] ip6_route_add+0x8a/0x160 net/ipv6/route.c:3903 inet6_rtm_newroute+0x2ba/0x1c90 net/ipv6/route.c:5567 rtnetlink_rcv_msg+0x869/0xfa0 net/core/rtnetlink.c:6472 netlink_rcv_skb+0x241/0x4d0 net/netlink/af_netlink.c:2545 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x751/0x8d0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d0/0xbf0 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x5ba/0x960 net/socket.c:2594 ___sys_sendmsg+0x2a6/0x360 net/socket.c:2648 __sys_sendmsg net/socket.c:2677 [inline] __do_sys_sendmsg net/socket.c:2686 [inline] __se_sys_sendmsg+0x1c2/0x2b0 net/socket.c:2684 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f6e1759c629 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f6e18539028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f6e17815fa0 RCX: 00007f6e1759c629 RDX: 0000000000000000 RSI: 0000200000004380 RDI: 0000000000000004 RBP: 00007f6e17632b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f6e17816038 R14: 00007f6e17815fa0 R15: 00007ffdbf58fdd8 Allocated by task 19771: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:384 kasan_kmalloc include/linux/kasan.h:198 [inline] __do_kmalloc_node mm/slab_common.c:1007 [inline] __kmalloc+0xb4/0x230 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:721 [inline] fib6_info_alloc+0x30/0xf0 net/ipv6/ip6_fib.c:155 ip6_route_info_create+0x44f/0x1240 net/ipv6/route.c:3803 ip6_route_add+0x28/0x160 net/ipv6/route.c:3899 inet6_rtm_newroute+0x2ba/0x1c90 net/ipv6/route.c:5567 rtnetlink_rcv_msg+0x869/0xfa0 net/core/rtnetlink.c:6472 netlink_rcv_skb+0x241/0x4d0 net/netlink/af_netlink.c:2545 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x751/0x8d0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d0/0xbf0 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x5ba/0x960 net/socket.c:2594 ___sys_sendmsg+0x2a6/0x360 net/socket.c:2648 __sys_sendmsg net/socket.c:2677 [inline] __do_sys_sendmsg net/socket.c:2686 [inline] __se_sys_sendmsg+0x1c2/0x2b0 net/socket.c:2684 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff888062609000 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 22 bytes to the right of allocated 184-byte region [ffff888062609000, ffff8880626090b8) The buggy address belongs to the physical page: page:ffffea0001898240 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff888062609300 pfn:0x62609 flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff888017c41a00 ffffea000138e250 ffffea000130cf10 raw: ffff888062609300 0000000000100005 00000001ffffffff 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 0x112820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 11685, tgid 11684 (syz.5.1837), ts 351046772147, free_ts 349028600555 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1581 prep_new_page mm/page_alloc.c:1588 [inline] get_page_from_freelist+0x1951/0x19e0 mm/page_alloc.c:3220 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4486 alloc_slab_page+0x5d/0x160 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5d/0x12f0 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x19e/0x250 mm/slub.c:3534 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa4/0x230 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:721 [inline] hash_ipportip6_resize+0xba6/0x1ca0 net/netfilter/ipset/ip_set_hash_gen.h:706 call_ad+0x454/0xb40 net/netfilter/ipset/ip_set_core.c:1757 ip_set_ad+0x81a/0x9c0 net/netfilter/ipset/ip_set_core.c:1841 nfnetlink_rcv_msg+0xbf0/0x12b0 net/netfilter/nfnetlink.c:302 netlink_rcv_skb+0x241/0x4d0 net/netlink/af_netlink.c:2545 nfnetlink_rcv+0x2c9/0x24a0 net/netfilter/nfnetlink.c:659 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x751/0x8d0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d0/0xbf0 net/netlink/af_netlink.c:1894 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1181 [inline] free_unref_page_prepare+0x7b2/0x8c0 mm/page_alloc.c:2365 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2458 rcu_do_batch kernel/rcu/tree.c:2194 [inline] rcu_core+0xcfb/0x1770 kernel/rcu/tree.c:2467 handle_softirqs+0x280/0x820 kernel/softirq.c:578 run_ksoftirqd+0xa8/0x100 kernel/softirq.c:950 smpboot_thread_fn+0x635/0xa00 kernel/smpboot.c:164 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Memory state around the buggy address: ffff888062608f80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff888062609000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888062609080: 00 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc ^ ffff888062609100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888062609180: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ==================================================================