[COPY FROM  ]

处理办法一：

Today I ran into a weird problem. I could not attach to my own process with gdb. The process ran under my UID, but gdb refused to attach. This is a problem of wrong permissions, although/proc/[pid]/status looked ok:

...Uid:    1000    1000    1000    1000Gid:    1000    1000    1000    1000...

I am the owner but cannot attach? Well, I launched gdb as root and could attach. Strange. Without digging deeper into this, my dirty workaround was this:

sudo chmod +s /usr/bin/gdb

Update: Thanks to Mario, who pointed out, that the reason is the Kernel hardening stuff build into the Ubuntu kernel. See  how to fix the problem permanently.

 

处理办法二：

I found the issue:

And the solution is just either do this (as root):

$ echo 0 > /proc/sys/kernel/yama/ptrace_scope

…or make it permanent by setting ptrace_scope to 0 in /etc/sysctl.d/10-ptrace.conf

Hope you find it useful!