| From bippy-5f407fcff5a0 Mon Sep 17 00:00:00 2001 |
| From: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| To: <linux-cve-announce@vger.kernel.org> |
| Reply-to: <cve@kernel.org>, <linux-kernel@vger.kernel.org> |
| Subject: CVE-2024-26951: wireguard: netlink: check for dangling peer via is_dead instead of empty list |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| wireguard: netlink: check for dangling peer via is_dead instead of empty list |
| |
| If all peers are removed via wg_peer_remove_all(), rather than setting |
| peer_list to empty, the peer is added to a temporary list with a head on |
| the stack of wg_peer_remove_all(). If a netlink dump is resumed and the |
| cursored peer is one that has been removed via wg_peer_remove_all(), it |
| will iterate from that peer and then attempt to dump freed peers. |
| |
| Fix this by instead checking peer->is_dead, which was explictly created |
| for this purpose. Also move up the device_update_lock lockdep assertion, |
| since reading is_dead relies on that. |
| |
| It can be reproduced by a small script like: |
| |
| echo "Setting config..." |
| ip link add dev wg0 type wireguard |
| wg setconf wg0 /big-config |
| ( |
| while true; do |
| echo "Showing config..." |
| wg showconf wg0 > /dev/null |
| done |
| ) & |
| sleep 4 |
| wg setconf wg0 <(printf "[Peer]\nPublicKey=$(wg genkey)\n") |
| |
| Resulting in: |
| |
| BUG: KASAN: slab-use-after-free in __lock_acquire+0x182a/0x1b20 |
| Read of size 8 at addr ffff88811956ec70 by task wg/59 |
| CPU: 2 PID: 59 Comm: wg Not tainted 6.8.0-rc2-debug+ #5 |
| Call Trace: |
| <TASK> |
| dump_stack_lvl+0x47/0x70 |
| print_address_description.constprop.0+0x2c/0x380 |
| print_report+0xab/0x250 |
| kasan_report+0xba/0xf0 |
| __lock_acquire+0x182a/0x1b20 |
| lock_acquire+0x191/0x4b0 |
| down_read+0x80/0x440 |
| get_peer+0x140/0xcb0 |
| wg_get_device_dump+0x471/0x1130 |
| |
| The Linux kernel CVE team has assigned CVE-2024-26951 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 5.6 with commit e7096c131e5161fa3b8e52a650d7719d2857adfd and fixed in 5.10.215 with commit f52be46e3e6ecefc2539119784324f0cbc09620a |
| Issue introduced in 5.6 with commit e7096c131e5161fa3b8e52a650d7719d2857adfd and fixed in 5.15.154 with commit 710a177f347282eea162aec8712beb1f42d5ad87 |
| Issue introduced in 5.6 with commit e7096c131e5161fa3b8e52a650d7719d2857adfd and fixed in 6.1.84 with commit b7cea3a9af0853fdbb1b16633a458f991dde6aac |
| Issue introduced in 5.6 with commit e7096c131e5161fa3b8e52a650d7719d2857adfd and fixed in 6.6.24 with commit 13d107794304306164481d31ce33f8fdb25a9c04 |
| Issue introduced in 5.6 with commit e7096c131e5161fa3b8e52a650d7719d2857adfd and fixed in 6.7.12 with commit 7bedfe4cfa38771840a355970e4437cd52d4046b |
| Issue introduced in 5.6 with commit e7096c131e5161fa3b8e52a650d7719d2857adfd and fixed in 6.8.3 with commit 302b2dfc013baca3dea7ceda383930d9297d231d |
| Issue introduced in 5.6 with commit e7096c131e5161fa3b8e52a650d7719d2857adfd and fixed in 6.9 with commit 55b6c738673871c9b0edae05d0c97995c1ff08c4 |
| |
| 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-2024-26951 |
| 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/wireguard/netlink.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/f52be46e3e6ecefc2539119784324f0cbc09620a |
| https://git.kernel.org/stable/c/710a177f347282eea162aec8712beb1f42d5ad87 |
| https://git.kernel.org/stable/c/b7cea3a9af0853fdbb1b16633a458f991dde6aac |
| https://git.kernel.org/stable/c/13d107794304306164481d31ce33f8fdb25a9c04 |
| https://git.kernel.org/stable/c/7bedfe4cfa38771840a355970e4437cd52d4046b |
| https://git.kernel.org/stable/c/302b2dfc013baca3dea7ceda383930d9297d231d |
| https://git.kernel.org/stable/c/55b6c738673871c9b0edae05d0c97995c1ff08c4 |
