Permission denied: '/tmp/tmpkjqha77c/rendered_template-63.py.out'

[Sovetnikov]

Running memory_analyzer under root for process that is run under regular user and got this output from memory_analyzer
Additionally sentry reporter generated event with "Permission denied: '/tmp/tmpkjqha77c/rendered_template-63.py.out'"
Seems temporary file with python code has root only permissions.

memory_analyzer run 63 -debug

Analyzing pid 63
Setting up GDB for pid 63
bug: No such file or directory.
[New LWP 384]
[New LWP 498]
[New LWP 499]
[New LWP 500]
[New LWP 501]
[New LWP 502]
[New LWP 503]
[New LWP 504]
[New LWP 768]
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
0x00007f9d8dec8037 in __GI___select (nfds=nfds@entry=0, readfds=readfds@entry=0x0, writefds=writefds@entry=0x0, exceptfds=exceptfds@entry=0x0, timeout=timeout@entry=0x7fff82826910) at ../sysdeps/unix/sysv/linux/select.c:41
41 ../sysdeps/unix/sysv/linux/select.c: No such file or directory.
+set directories /usr/local/lib/python3.7/site-packages/memory_analyzer/
+py sys.path.append("/usr/local/lib/python3.7/site-packages/memory_analyzer/")
++file_command /tmp/tmpkjqha77c/rendered_template-63.py.out
GIL $1
+++call (void) PyRun_SimpleString("with open('/tmp/tmpkjqha77c/rendered_template-63.py.out') as f: exec(f.read())")
+++call (void) PyGILState_Release($1)
[Inferior 1 (process 63) detached]
Gathering data...
ERROR: Analysis for 63 returned no data! Try rerunning with --debug
ERROR: No results to report

su user

$ cat /tmp/tmpkjqha77c/rendered_template-63.py.out
cat: /tmp/tmpkjqha77c/rendered_template-63.py.out: Permission denied
$ ls -alF /tmp
total 32
drwxrwxrwt 1 root root 4096 Dec 5 09:04 ./
drwxr-xr-x 1 root root 4096 Dec 5 09:01 ../
drwx------ 2 root root 4096 Dec 5 09:04 tmpkjqha77c/

[Sovetnikov]

Running target process under root solves this issue

[thatch]

What is your umask when you are about to run memory analyzer as root?

[Sovetnikov]

Set as default

umask

0022

[thatch]

@lisroach memory_analyzer.memory_analyzer uses mkdtemp which says "The directory is readable, writable, and searchable only by the creating user ID." I don't see any way to customize the umask it uses; we can probably do something like

try:
  os.chmod(..., 0o755)
except:
  pass

to make it more widely readable. I don't know about looking at the owner of the process you're analyzing, because that might get us into a place where we can't delete it when we're done?