memory leak in vlan_vid_add

Status: fixed on 2026/08/17 15:57
Subsystems: net
Labels: prio:normal
[Documentation on labels]
Reported-by: syzbot+456957213f32970c0762@syzkaller.appspotmail.com
Fix commit: dcf15eaf5641 net: hsr: fix memory leak on slave unregistration by removing synced VLANs
First crash: 50d, last: 33d
▶ ▼ ✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
5b22b1d6 assessment-security DenialOfService: ✅ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ✅ VMGuestTrigger: ❌ VMHostTrigger: ❌ ❓ memory leak in vlan_vid_add 2026/07/04 08:21 2026/07/04 08:21 2026/07/04 08:54 93f57954
▶ ▼ Discussions (3)
Title Replies (including bot) Last reply
[PATCH v2 net] net: hsr: fix memory leak on slave unregistration by removing synced VLANs 4 (4) 2026/07/22 18:10
[PATCH net] net: hsr: fix memory leak on slave unregistration by removing synced VLANs 6 (6) 2026/07/21 10:05
[syzbot] [net?] memory leak in vlan_vid_add 0 (1) 2026/07/07 08:20
▶ ▼ Last patch testing requests (2)
Created Duration User Patch Repo Result
2026/07/21 06:33 1h04m retest repro upstream report log
2026/07/06 14:56 30m edumazet@google.com patch upstream OK log

Sample crash report:
BUG: memory leak
unreferenced object 0xffff8881147f3c00 (size 256):
  comm "syz-executor", pid 5805, jiffies 4294943736
  hex dump (first 32 bytes):
    00 40 02 0b 81 88 ff ff 00 00 00 00 00 00 00 00  .@..............
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace (crc a66a6b91):
    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
    slab_post_alloc_hook mm/slub.c:4625 [inline]
    slab_alloc_node mm/slub.c:4945 [inline]
    __kmalloc_cache_noprof+0x356/0x440 mm/slub.c:5511
    _kmalloc_noprof include/linux/slab.h:969 [inline]
    _kzalloc_noprof include/linux/slab.h:1290 [inline]
    vlan_info_alloc net/8021q/vlan_core.c:153 [inline]
    vlan_vid_add+0x1ff/0x2b0 net/8021q/vlan_core.c:329
    vlan_vid0_add net/8021q/vlan.c:349 [inline]
    vlan_device_event.cold+0x27/0x65 net/8021q/vlan.c:388
    notifier_call_chain+0x59/0x160 kernel/notifier.c:85
    call_netdevice_notifiers_info+0x7d/0xb0 net/core/dev.c:2250
    call_netdevice_notifiers_extack net/core/dev.c:2288 [inline]
    call_netdevice_notifiers net/core/dev.c:2302 [inline]
    __dev_notify_flags+0xb1/0x1b0 net/core/dev.c:9793
    netif_change_flags+0x71/0x90 net/core/dev.c:9822
    do_setlink.isra.0+0x50e/0x1ce0 net/core/rtnetlink.c:3215
    rtnl_changelink net/core/rtnetlink.c:3849 [inline]
    __rtnl_newlink net/core/rtnetlink.c:4022 [inline]
    rtnl_newlink+0xb23/0x1310 net/core/rtnetlink.c:4159
    rtnetlink_rcv_msg+0x52b/0x600 net/core/rtnetlink.c:7076
    netlink_rcv_skb+0x89/0x1c0 net/netlink/af_netlink.c:2556
    netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
    netlink_unicast+0x38f/0x4e0 net/netlink/af_netlink.c:1345
    netlink_sendmsg+0x335/0x690 net/netlink/af_netlink.c:1900
    sock_sendmsg_nosec net/socket.c:775 [inline]
    __sock_sendmsg net/socket.c:790 [inline]
    __sys_sendto+0x2ca/0x2e0 net/socket.c:2252
    __do_sys_sendto net/socket.c:2259 [inline]
    __se_sys_sendto net/socket.c:2255 [inline]
    __x64_sys_sendto+0x28/0x30 net/socket.c:2255
    do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
    do_syscall_64+0xf8/0x610 arch/x86/entry/syscall_64.c:94

BUG: memory leak
unreferenced object 0xffff8881127a3660 (size 32):
  comm "syz-executor", pid 5805, jiffies 4294943736
  hex dump (first 32 bytes):
    a0 3c 7f 14 81 88 ff ff a0 3c 7f 14 81 88 ff ff  .<.......<......
    81 00 00 00 01 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace (crc a6a88710):
    kmemleak_alloc_recursive include/linux/kmemleak.h:44 [inline]
    slab_post_alloc_hook mm/slub.c:4625 [inline]
    slab_alloc_node mm/slub.c:4945 [inline]
    __kmalloc_cache_noprof+0x356/0x440 mm/slub.c:5511
    _kmalloc_noprof include/linux/slab.h:969 [inline]
    _kzalloc_noprof include/linux/slab.h:1290 [inline]
    vlan_vid_info_alloc net/8021q/vlan_core.c:196 [inline]
    __vlan_vid_add net/8021q/vlan_core.c:302 [inline]
    vlan_vid_add+0x14f/0x2b0 net/8021q/vlan_core.c:336
    vlan_vid0_add net/8021q/vlan.c:349 [inline]
    vlan_device_event.cold+0x27/0x65 net/8021q/vlan.c:388
    notifier_call_chain+0x59/0x160 kernel/notifier.c:85
    call_netdevice_notifiers_info+0x7d/0xb0 net/core/dev.c:2250
    call_netdevice_notifiers_extack net/core/dev.c:2288 [inline]
    call_netdevice_notifiers net/core/dev.c:2302 [inline]
    __dev_notify_flags+0xb1/0x1b0 net/core/dev.c:9793
    netif_change_flags+0x71/0x90 net/core/dev.c:9822
    do_setlink.isra.0+0x50e/0x1ce0 net/core/rtnetlink.c:3215
    rtnl_changelink net/core/rtnetlink.c:3849 [inline]
    __rtnl_newlink net/core/rtnetlink.c:4022 [inline]
    rtnl_newlink+0xb23/0x1310 net/core/rtnetlink.c:4159
    rtnetlink_rcv_msg+0x52b/0x600 net/core/rtnetlink.c:7076
    netlink_rcv_skb+0x89/0x1c0 net/netlink/af_netlink.c:2556
    netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
    netlink_unicast+0x38f/0x4e0 net/netlink/af_netlink.c:1345
    netlink_sendmsg+0x335/0x690 net/netlink/af_netlink.c:1900
    sock_sendmsg_nosec net/socket.c:775 [inline]
    __sock_sendmsg net/socket.c:790 [inline]
    __sys_sendto+0x2ca/0x2e0 net/socket.c:2252
    __do_sys_sendto net/socket.c:2259 [inline]
    __se_sys_sendto net/socket.c:2255 [inline]
    __x64_sys_sendto+0x28/0x30 net/socket.c:2255
    do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
    do_syscall_64+0xf8/0x610 arch/x86/entry/syscall_64.c:94

connection error: failed to recv *flatrpc.ExecutorMessageRawT: EOF

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/07/04 08:21 upstream 71dfdfb0209b fcece630 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci-upstream-gce-leak memory leak in vlan_vid_add
* Struck through repros no longer work on HEAD.