我已经设置了 Ubuntu 21.04基础映像在 Termux 中。当我运行 时apt update，出现以下错误。由于无法运行apt update，因此无法安装任何软件包。
root@localhost:~# apt update
Get:1 http://ports.ubuntu.com/ubuntu-ports hirsute InRelease [269 kB]
Get:2 http://ports.ubuntu.com/ubuntu-ports hirsute-updates InRelease [109 kB]
Get:3 http://ports.ubuntu.com/ubuntu-ports hirsute-backports InRelease [90.7 kB]
Get:4 http://ports.ubuntu.com/ubuntu-ports hirsute-security InRelease [101 kB]
Reading package lists... Done
E: Unable to determine file size for fd 7 - fstat (1: Operation not permitted)
E: The repository 'http://ports.ubuntu.com/ubuntu-ports hirsute InRelease' provides only weak security information.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: Unable to determine file size for fd 7 - fstat (1: Operation not permitted)
E: The repository 'http://ports.ubuntu.com/ubuntu-ports hirsute-updates InRelease' provides only weak security information.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: Unable to determine file size for fd 7 - fstat (1: Operation not permitted)
E: The repository 'http://ports.ubuntu.com/ubuntu-ports hirsute-backports InRelease' provides only weak security information.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: Unable to determine file size for fd 7 - fstat (1: Operation not permitted)
E: The repository 'http://ports.ubuntu.com/ubuntu-ports hirsute-security InRelease' provides only weak security information.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
如何修复？20.04.2 基础映像中不存在此错误。
以下是 的权限的输出/tmp。
root@localhost:~# ls -ld /tmp
drwx------ 2 root root 3488 Jul 1 10:54 /tmp
这是sources.list（我有不是对其进行了修改）。
root@localhost:~# cat /etc/apt/sources.list
# See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to
# newer versions of the distribution.
deb http://ports.ubuntu.com/ubuntu-ports/ hirsute main restricted
# deb-src http://ports.ubuntu.com/ubuntu-ports/ hirsute main restricted
## Major bug fix updates produced after the final release of the
## distribution.
deb http://ports.ubuntu.com/ubuntu-ports/ hirsute-updates main restricted
# deb-src http://ports.ubuntu.com/ubuntu-ports/ hirsute-updates main restricted
## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team. Also, please note that software in universe WILL NOT receive any
## review or updates from the Ubuntu security team.
deb http://ports.ubuntu.com/ubuntu-ports/ hirsute universe
# deb-src http://ports.ubuntu.com/ubuntu-ports/ hirsute universe
deb http://ports.ubuntu.com/ubuntu-ports/ hirsute-updates universe
# deb-src http://ports.ubuntu.com/ubuntu-ports/ hirsute-updates universe
## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu
## team, and may not be under a free licence. Please satisfy yourself as to
## your rights to use the software. Also, please note that software in
## multiverse WILL NOT receive any review or updates from the Ubuntu
## security team.
deb http://ports.ubuntu.com/ubuntu-ports/ hirsute multiverse
# deb-src http://ports.ubuntu.com/ubuntu-ports/ hirsute multiverse
deb http://ports.ubuntu.com/ubuntu-ports/ hirsute-updates multiverse
# deb-src http://ports.ubuntu.com/ubuntu-ports/ hirsute-updates multiverse
## N.B. software from this repository may not have been tested as
## extensively as that contained in the main release, although it includes
## newer versions of some applications which may provide useful features.
## Also, please note that software in backports WILL NOT receive any review
## or updates from the Ubuntu security team.
deb http://ports.ubuntu.com/ubuntu-ports/ hirsute-backports main restricted universe multiverse
# deb-src http://ports.ubuntu.com/ubuntu-ports/ hirsute-backports main restricted universe multiverse
## Uncomment the following two lines to add software from Canonical's
## 'partner' repository.
## This software is not part of Ubuntu, but is offered by Canonical and the
## respective vendors as a service to Ubuntu users.
# deb http://archive.canonical.com/ubuntu hirsute partner
# deb-src http://archive.canonical.com/ubuntu hirsute partner
deb http://ports.ubuntu.com/ubuntu-ports/ hirsute-security main restricted
# deb-src http://ports.ubuntu.com/ubuntu-ports/ hirsute-security main restricted
deb http://ports.ubuntu.com/ubuntu-ports/ hirsute-security universe
# deb-src http://ports.ubuntu.com/ubuntu-ports/ hirsute-security universe
deb http://ports.ubuntu.com/ubuntu-ports/ hirsute-security multiverse
# deb-src http://ports.ubuntu.com/ubuntu-ports/ hirsute-security multiverse
答案1
正确的权限：
sudo chmod 777 -R /tmp
答案2
请使用以下命令找到 apt update 的 PID：
ps ax | grep "apt"
当您知道类型时：
ls -al /proc/PID/fd/
其中PID是您之前获得的进程号。
名为 7 的文件描述符是什么？
更新 2021-07-05：
或许这是正常的。
根据 Termux 文档https://wiki.termux.com/wiki/Package_Management：
限制在 root 下使用 Apt，以防止混淆 Android /data 分区上的所有权和 SELinux 标签。
我们强烈建议使用 pkg 实用程序，而不是直接使用 apt...
不支持降级。为了回收磁盘空间，我们不保留软件包版本的历史记录。