| From bippy-1.2.0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@kernel.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2025-22103: net: fix NULL pointer dereference in l3mdev_l3_rcv |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| net: fix NULL pointer dereference in l3mdev_l3_rcv |
| |
| When delete l3s ipvlan: |
| |
| ip link del link eth0 ipvlan1 type ipvlan mode l3s |
| |
| This may cause a null pointer dereference: |
| |
| Call trace: |
| ip_rcv_finish+0x48/0xd0 |
| ip_rcv+0x5c/0x100 |
| __netif_receive_skb_one_core+0x64/0xb0 |
| __netif_receive_skb+0x20/0x80 |
| process_backlog+0xb4/0x204 |
| napi_poll+0xe8/0x294 |
| net_rx_action+0xd8/0x22c |
| __do_softirq+0x12c/0x354 |
| |
| This is because l3mdev_l3_rcv() visit dev->l3mdev_ops after |
| ipvlan_l3s_unregister() assign the dev->l3mdev_ops to NULL. The process |
| like this: |
| |
| (CPU1) | (CPU2) |
| l3mdev_l3_rcv() | |
| check dev->priv_flags: | |
| master = skb->dev; | |
| | |
| | ipvlan_l3s_unregister() |
| | set dev->priv_flags |
| | dev->l3mdev_ops = NULL; |
| | |
| visit master->l3mdev_ops | |
| |
| To avoid this by do not set dev->l3mdev_ops when unregister l3s ipvlan. |
| |
| The Linux kernel CVE team has assigned CVE-2025-22103 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.1 with commit c675e06a98a474f7ad0af32ce467613da818da52 and fixed in 6.14.2 with commit f9dff65140efc289f01bcf39c3ca66a8806b6132 |
| Issue introduced in 5.1 with commit c675e06a98a474f7ad0af32ce467613da818da52 and fixed in 6.15 with commit 0032c99e83b9ce6d5995d65900aa4b6ffb501cce |
| |
| Please see https://www.kernel.org for a full list of currently supported |
| kernel versions by the kernel community. |
| |
| Unaffected versions might change over time as fixes are backported to |
| older supported kernel versions. The official CVE entry at |
| https://cve.org/CVERecord/?id=CVE-2025-22103 |
| will be updated if fixes are backported, please check that for the most |
| up to date information about this issue. |
| |
| |
| Affected files |
| ============== |
| |
| The file(s) affected by this issue are: |
| drivers/net/ipvlan/ipvlan_l3s.c |
| |
| |
| Mitigation |
| ========== |
| |
| The Linux kernel CVE team recommends that you update to the latest |
| stable kernel version for this, and many other bugfixes. Individual |
| changes are never tested alone, but rather are part of a larger kernel |
| release. Cherry-picking individual commits is not recommended or |
| supported by the Linux kernel community at all. If however, updating to |
| the latest release is impossible, the individual changes to resolve this |
| issue can be found at these commits: |
| https://git.kernel.org/stable/c/f9dff65140efc289f01bcf39c3ca66a8806b6132 |
| https://git.kernel.org/stable/c/0032c99e83b9ce6d5995d65900aa4b6ffb501cce |
