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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal">I would like to be able to audit the syscalls that the chattr command uses but I’m not having much luck.<o:p></o:p></p>
<p class="MsoNormal">In an effort to see the syscalls used, I created a rule to log all syscalls, like this:<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:36.0pt"># auditctl -a exit,always -F path=/root/file<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Then run this:<o:p></o:p></p>
<p class="MsoNormal" style="margin-left:36.0pt"># chattr +i /root/file<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">This produces series of two syscalls in the logs, 6 (sys_newlstat) and 2 (sys_open):<o:p></o:p></p>
<p class="MsoNormal">node=localhost.localdomain type=SYSCALL msg=audit(1314189320.335:53158): arch=c000003e syscall=6 success=yes exit=0 a0=7ffff0f8886c a1=7ffff0f88250 a2=7ffff0f88250 a3=1 items=1 ppid=15560 pid=15745 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0
egid=0 sgid=0 fsgid=0 tty=pts0 ses=1198 comm="chattr" exe="/usr/bin/chattr" key=(null)<o:p></o:p></p>
<p class="MsoNormal">node=localhost.localdomain type=SYSCALL msg=audit(1314189320.335:53160): arch=c000003e syscall=2 success=yes exit=3 a0=7ffff0f8886c a1=800 a2=7ffff0f88170 a3=1 items=1 ppid=15560 pid=15745 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0
sgid=0 fsgid=0 tty=pts0 ses=1198 comm="chattr" exe="/usr/bin/chattr" key=(null)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I don’t think these are the syscalls I want to audit, they would be far too frequent. I also noticed when I run a strace on the chattr command it looks like it uses ioctl, eg:<o:p></o:p></p>
<p class="MsoNormal">ioctl(3, EXT2_IOC_SETFLAGS, 0x7fff0314cf3c)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">What audit rule could I use to achieve this? Is it a combination of specifying syscall 6 or 2 with some of a0, a1 or a2? Or is this not possible?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’ve tried auditing file attribute changes (auditctl -a exit,always -F arch=b64 -p a) but it does not work.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Many thanks,<o:p></o:p></p>
<p class="MsoNormal">Max Williams<o:p></o:p></p>
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