| 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-2022-49687: virtio_net: fix xdp_rxq_info bug after suspend/resume |
| |
| Description |
| =========== |
| |
| In the Linux kernel, the following vulnerability has been resolved: |
| |
| virtio_net: fix xdp_rxq_info bug after suspend/resume |
| |
| The following sequence currently causes a driver bug warning |
| when using virtio_net: |
| |
| # ip link set eth0 up |
| # echo mem > /sys/power/state (or e.g. # rtcwake -s 10 -m mem) |
| <resume> |
| # ip link set eth0 down |
| |
| Missing register, driver bug |
| WARNING: CPU: 0 PID: 375 at net/core/xdp.c:138 xdp_rxq_info_unreg+0x58/0x60 |
| Call trace: |
| xdp_rxq_info_unreg+0x58/0x60 |
| virtnet_close+0x58/0xac |
| __dev_close_many+0xac/0x140 |
| __dev_change_flags+0xd8/0x210 |
| dev_change_flags+0x24/0x64 |
| do_setlink+0x230/0xdd0 |
| ... |
| |
| This happens because virtnet_freeze() frees the receive_queue |
| completely (including struct xdp_rxq_info) but does not call |
| xdp_rxq_info_unreg(). Similarly, virtnet_restore() sets up the |
| receive_queue again but does not call xdp_rxq_info_reg(). |
| |
| Actually, parts of virtnet_freeze_down() and virtnet_restore_up() |
| are almost identical to virtnet_close() and virtnet_open(): only |
| the calls to xdp_rxq_info_(un)reg() are missing. This means that |
| we can fix this easily and avoid such problems in the future by |
| just calling virtnet_close()/open() from the freeze/restore handlers. |
| |
| Aside from adding the missing xdp_rxq_info calls the only difference |
| is that the refill work is only cancelled if netif_running(). However, |
| this should not make any functional difference since the refill work |
| should only be active if the network interface is actually up. |
| |
| The Linux kernel CVE team has assigned CVE-2022-49687 to this issue. |
| |
| |
| Affected and fixed versions |
| =========================== |
| |
| Issue introduced in 4.16 with commit 754b8a21a96d5f11712245aef907149606b323ae and fixed in 4.19.250 with commit 9222672fa6370f0ec3d899662cb8680e9282fc4c |
| Issue introduced in 4.16 with commit 754b8a21a96d5f11712245aef907149606b323ae and fixed in 5.4.202 with commit 8c7a32b7c15555beddc5810c3334d9cefff061bf |
| Issue introduced in 4.16 with commit 754b8a21a96d5f11712245aef907149606b323ae and fixed in 5.10.127 with commit 340fbdc8011f2dc678f622c5ce1cbb5ab8305de7 |
| Issue introduced in 4.16 with commit 754b8a21a96d5f11712245aef907149606b323ae and fixed in 5.15.51 with commit 8d7fe9ad6fddc2af8bde4b921b4f8fab231ed38c |
| Issue introduced in 4.16 with commit 754b8a21a96d5f11712245aef907149606b323ae and fixed in 5.18.8 with commit 57ee40f1b198b59d43c216fbc4672f9300d3c8b0 |
| Issue introduced in 4.16 with commit 754b8a21a96d5f11712245aef907149606b323ae and fixed in 5.19 with commit 8af52fe9fd3bf5e7478da99193c0632276e1dfce |
| |
| 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-2022-49687 |
| 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/virtio_net.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/9222672fa6370f0ec3d899662cb8680e9282fc4c |
| https://git.kernel.org/stable/c/8c7a32b7c15555beddc5810c3334d9cefff061bf |
| https://git.kernel.org/stable/c/340fbdc8011f2dc678f622c5ce1cbb5ab8305de7 |
| https://git.kernel.org/stable/c/8d7fe9ad6fddc2af8bde4b921b4f8fab231ed38c |
| https://git.kernel.org/stable/c/57ee40f1b198b59d43c216fbc4672f9300d3c8b0 |
| https://git.kernel.org/stable/c/8af52fe9fd3bf5e7478da99193c0632276e1dfce |
