================================================================== BUG: KASAN: slab-use-after-free in rose_get_neigh+0x391/0x990 net/rose/rose_route.c:692 Read of size 1 at addr ffff88802db3ec30 by task syz.2.26/6791 CPU: 0 UID: 0 PID: 6791 Comm: syz.2.26 Not tainted 6.15.0-rc7-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:408 [inline] print_report+0xb4/0x290 mm/kasan/report.c:521 kasan_report+0x118/0x150 mm/kasan/report.c:634 rose_get_neigh+0x391/0x990 net/rose/rose_route.c:692 rose_connect+0x415/0x1070 net/rose/af_rose.c:816 __sys_connect_file net/socket.c:2038 [inline] __sys_connect+0x32c/0x450 net/socket.c:2057 __do_sys_connect net/socket.c:2063 [inline] __se_sys_connect net/socket.c:2060 [inline] __x64_sys_connect+0x7a/0x90 net/socket.c:2060 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x7f/0x160 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f5206f8e969 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:00007f5207e40038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: ffffffffffffffda RBX: 00007f52071b5fa0 RCX: 00007f5206f8e969 RDX: 000000000000001c RSI: 0000200000000040 RDI: 0000000000000008 RBP: 00007f5207010ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f52071b5fa0 R15: 00007ffdc796a388 Allocated by task 6762: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 poison_kmalloc_redzone mm/kasan/common.c:377 [inline] __kasan_kmalloc+0x72/0x90 mm/kasan/common.c:394 kasan_kmalloc include/linux/kasan.h:260 [inline] __kmalloc_cache_noprof+0x22b/0x3a0 mm/slub.c:4358 kmalloc_noprof include/linux/slab.h:905 [inline] rose_add_node+0x23a/0xde0 net/rose/rose_route.c:85 rose_rt_ioctl+0xa48/0xfb0 net/rose/rose_route.c:747 rose_ioctl+0x3ce/0x8b0 net/rose/af_rose.c:1380 sock_do_ioctl+0xd9/0x300 net/socket.c:1190 sock_ioctl+0x576/0x790 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x7f/0x160 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e Freed by task 6789: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:576 poison_slab_object mm/kasan/common.c:247 [inline] __kasan_slab_free+0x37/0x50 mm/kasan/common.c:264 kasan_slab_free include/linux/kasan.h:233 [inline] slab_free_hook mm/slub.c:2380 [inline] slab_free mm/slub.c:4642 [inline] kfree+0x19c/0x440 mm/slub.c:4841 rose_rt_device_down+0x66d/0x6c0 net/rose/rose_route.c:522 rose_device_event+0x5ef/0x680 net/rose/af_rose.c:248 notifier_call_chain+0x1b3/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2214 [inline] call_netdevice_notifiers net/core/dev.c:2228 [inline] __dev_notify_flags+0x18d/0x2e0 net/core/dev.c:-1 netif_change_flags+0xe8/0x1a0 net/core/dev.c:9422 dev_change_flags+0x130/0x260 net/core/dev_api.c:68 dev_ioctl+0x7b4/0x1150 net/core/dev_ioctl.c:821 sock_do_ioctl+0x22c/0x300 net/socket.c:1204 sock_ioctl+0x576/0x790 net/socket.c:1311 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:906 [inline] __se_sys_ioctl+0xf9/0x170 fs/ioctl.c:892 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x7f/0x160 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x76/0x7e The buggy address belongs to the object at ffff88802db3ec00 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 48 bytes inside of freed 512-byte region [ffff88802db3ec00, ffff88802db3ee00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2db3c head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff888019441c80 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff888019441c80 dead000000000122 0000000000000000 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 00fff00000000002 ffffea0000b6cf01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000004 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6513, tgid 6513 (syz-executor), ts 147986667740, free_ts 147678574324 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1d0/0x220 mm/page_alloc.c:1714 prep_new_page mm/page_alloc.c:1722 [inline] get_page_from_freelist+0x2b6b/0x2d10 mm/page_alloc.c:3684 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:4966 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2301 alloc_slab_page mm/slub.c:2450 [inline] allocate_slab+0x8a/0x3a0 mm/slub.c:2618 new_slab mm/slub.c:2672 [inline] ___slab_alloc+0xc48/0x14d0 mm/slub.c:3858 __slab_alloc mm/slub.c:3948 [inline] __slab_alloc_node mm/slub.c:4023 [inline] slab_alloc_node mm/slub.c:4184 [inline] __do_kmalloc_node mm/slub.c:4326 [inline] __kmalloc_noprof+0x300/0x4b0 mm/slub.c:4339 kmalloc_noprof include/linux/slab.h:909 [inline] kzalloc_noprof include/linux/slab.h:1039 [inline] fib6_info_alloc+0x30/0xf0 net/ipv6/ip6_fib.c:155 ip6_route_info_create+0x44f/0x11c0 net/ipv6/route.c:3802 ip6_route_add+0x28/0x130 net/ipv6/route.c:3896 addrconf_add_mroute net/ipv6/addrconf.c:2551 [inline] addrconf_add_dev+0x24f/0x330 net/ipv6/addrconf.c:2569 addrconf_dev_config net/ipv6/addrconf.c:3477 [inline] addrconf_init_auto_addrs+0x5cf/0xb40 net/ipv6/addrconf.c:3571 addrconf_notify+0xacc/0x1010 net/ipv6/addrconf.c:3744 notifier_call_chain+0x1b3/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2214 [inline] call_netdevice_notifiers net/core/dev.c:2228 [inline] __dev_notify_flags+0x18d/0x2e0 net/core/dev.c:-1 netif_change_flags+0xe8/0x1a0 net/core/dev.c:9422 page last free pid 5063 tgid 5063 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1258 [inline] __free_frozen_pages+0xafe/0xcb0 mm/page_alloc.c:2721 discard_slab mm/slub.c:2716 [inline] __put_partials+0x15f/0x1b0 mm/slub.c:3185 put_cpu_partial+0x17c/0x250 mm/slub.c:3260 __slab_free+0x2f7/0x400 mm/slub.c:4512 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x9a/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x60 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:250 [inline] slab_post_alloc_hook mm/slub.c:4147 [inline] slab_alloc_node mm/slub.c:4196 [inline] kmem_cache_alloc_node_noprof+0x1b5/0x380 mm/slub.c:4248 __alloc_skb+0x112/0x2d0 net/core/skbuff.c:658 alloc_skb include/linux/skbuff.h:1340 [inline] alloc_skb_with_frags+0xca/0x890 net/core/skbuff.c:6639 sock_alloc_send_pskb+0x857/0x990 net/core/sock.c:2954 unix_dgram_sendmsg+0x5b3/0x17b0 net/unix/af_unix.c:2007 sock_sendmsg_nosec net/socket.c:712 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:727 __sys_sendto+0x3ca/0x520 net/socket.c:2180 __do_sys_sendto net/socket.c:2187 [inline] __se_sys_sendto net/socket.c:2183 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2183 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x7f/0x160 arch/x86/entry/syscall_64.c:94 Memory state around the buggy address: ffff88802db3eb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802db3eb80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88802db3ec00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802db3ec80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802db3ed00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================