Bug 1732691 - Bash shell problem
Summary: Bash shell problem
Keywords:
Status: NEW
Alias: None
Product: Red Hat Enterprise Linux 7
Classification: Red Hat
Component: bash
Version: 7.0
Hardware: x86_64
OS: All
unspecified
high
Target Milestone: rc
: ---
Assignee: Siteshwar Vashisht
QA Contact: Karel Volný
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2019-07-24 07:06 UTC by 晓俊
Modified: 2019-07-24 07:10 UTC (History)
0 users

Fixed In Version:
Doc Type: If docs needed, set a value
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Clone Of:
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Last Closed:
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Attachments (Terms of Use)

Description 晓俊 2019-07-24 07:06:39 UTC
Hello Red Hat, there is a test BUG for your 7 products, the content is Chinese, please understand


问题复现:
首先 useradd ttt 创建一个账号
然后 su - ttt 进入账户 
这里注意 直接 su 输入密码 进入管理员 (这里就会留下一个BASH的进程)
当 userdel -r ttt 时 就会报错 提示有进程正在使用
解决方案是 ps -ef |grep 报错的PID 查到PID
然后kill -9 PID 
但是这样 内核就会崩溃 然后现在用的BASH也不好使了 就是输入不了命令 都是空格
想问下这个问题是什么原因造成的 还是是系统的BUG原理是什么
以下是演示截图:

go to annex!

PS:正常如果 su - ttt 然后 logout 然后再操作userdel -r ttt是没有问题的
第二次测试的时候 虚拟机 也死了 很恐怖 自己输入了exit  然后就没了~ bash 终端就被关闭了 再打开就可以了

annex:

1.20190723225059Thinkmail@377972706.png

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2.20190723225059Thinkmail@377972835.png

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3.20190723225059Thinkmail@377973169.png

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The attachment is the first time that the connection is automatically sent to the customer service via email.


Problem recurrence:
First useradd ttt create an account
Then su - ttt enters the account
Note here directly su Enter the password Enter the administrator (here will leave a BASH process)
When userdel -r ttt will report an error, indicating that a process is in use.
The solution is ps -ef |grep error PID found PID
Then kill -9 PID
But the kernel will crash, and the BASH that is used now is not good. It is impossible to enter the command.
I want to ask what is the cause of this problem or what is the principle of the system BUG?
The following is a demo screenshot:



PS: Normal if su - ttt then logout and then operate userdel -r ttt is no problem
The second test, the virtual machine is also dead, very scary, I entered the exit and then it is gone~ the bash terminal is closed, and then it can be opened.


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