Additional parameter in PROCTITLE.proctitle when executing rm

[Todd Heberlein]

Side note:

I found on some previous versions of CentOS 7 that if you audit a system call that often comes before the exec() system call (e.g., auditing close() which is called a number of times after a fork but before an exec), the PROCTITLE field will be for the parent process and not the new process.

I am guessing that PROCTITLE is set at the first audit record (e.g., close() ) and isn’t reset later such as when the exec() is called.

(I haven’t tested this on recent versions of CentOS or RHEL)

Todd


> On Mar 18, 2021, at 1:13 PM, Richard Guy Briggs <rgb at redhat.com> wrote:
> 
> On 2021-03-18 16:31, Alan Evangelista wrote:
>> I'm trying to audit commands run in bash, including the commands arguments.
>> The proctitle parameter in the PROCTITLE record seems to be the most
>> reliable source to get that, but it does not contain exactly the "rm"
>> command I have typed on bash. Example:
>> 
>> 1) rm /data/test2,txt -f
>> 
>> type=SYSCALL msg=audit(1616095201.302:40381): arch=c000003e syscall=263 success=yes exit=0 a0=ffffffffffffff9c a1=1b1f0c0 a2=0 a3=7fff3677a720 items=3 ppid=15954 pid=3398 auid=201327714 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=pts0 ses=2663 comm="rm" exe="/usr/bin/rm" key="filesystem_op"
>> type=CWD msg=audit(1616095201.302:40381):  cwd="/home/aevangelista"
>> type=PATH msg=audit(1616095201.302:40381): item=0 name="/data/test2.txt" inode=38030531 dev=08:11 mode=0100644 ouid=0 ogid=0 rdev=00:00 objtype=NORMAL cap_fp=0000000000000000 cap_fi=0000000000000000 cap_fe=0 cap_fver=0
>> type=PATH msg=audit(1616095201.302:40381): item=1 name="/data/" inode=64 dev=08:11 mode=040755 ouid=0 ogid=0 rdev=00:00 objtype=PARENT cap_fp=0000000000000000 cap_fi=0000000000000000 cap_fe=0 cap_fver=0 type=PATH msg=audit(1616095201.302:40381): item=2 name="/data/test2.txt" inode=38030531 dev=08:11 mode=0100644 ouid=0 ogid=0 rdev=00:00 objtype=DELETE cap_fp=0000000000000000 cap_fi=0000000000000000 cap_fe=0 cap_fver=0
>> type=PROCTITLE msg=audit(1616095201.302:40381): proctitle=726D002D69002F646174612F74657374322E747874002D66
>> 
>> The proctitle value  726D002D69002F646174612F74657374322E747874002D66 is
>> equal to "rm-i /data/test2.txt -f" in ASCII. Where did this -i come from?
>> Is it expected?
> 
> At first, this looks like something left over from the "-i" parameter
> supplied to ausearch to interpret the values in the audit records to
> give you that plaintext.
> 
> But more likely, it is an alias in ~/.bashrc, ~/.bash-profile,
> ~/.profile, /etc/bashrc, /etc/bash.bashrc, /etc/profile,
> /etc/profile.d/* that is nannying you to be sure you meant to delete
> what you are asking to delete.
> 
> This can be overridden with -f.  rm(1) options preceed the filespec.
> 
>> Alan
> 
> - RGB
> 
> --
> Richard Guy Briggs <rgb at redhat.com>
> Sr. S/W Engineer, Kernel Security, Base Operating Systems
> Remote, Ottawa, Red Hat Canada
> IRC: rgb, SunRaycer
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