Bug 1646521
| Summary: | firefox cannot run in SELinux sandbox | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 7 | Reporter: | Milos Malik <mmalik> |
| Component: | selinux-policy | Assignee: | Lukas Vrabec <lvrabec> |
| Status: | CLOSED ERRATA | QA Contact: | Milos Malik <mmalik> |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | 7.6 | CC: | jfrieben, lvrabec, mmalik, plautrba, ssekidde, vmojzis |
| Target Milestone: | rc | ||
| Target Release: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | If docs needed, set a value | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2019-08-06 12:52:54 UTC | Type: | Bug |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
| Bug Depends On: | |||
| Bug Blocks: | 1653106 | ||
*** Bug 1663876 has been marked as a duplicate of this bug. *** An unconfined user can run firefox in sandbox using following commands:
1) sandbox -X firefox
2) sandbox -X -t sandbox_min_t firefox
3) sandbox -X -t sandbox_net_t firefox
4) sandbox -X -t sandbox_x_t firefox
5) sandbox -X -t sandbox_web_t firefox
Firefox starts and runs successfully in all above-mentioned cases. Firefox can access network in cases 2, 3, 5. Firefox cannot access network in cases 1 and 5, which is expected. These commands trigger various SELinux denials which are expected because of the nature of sandbox.
# rpm -qa selinux\* \*sandbox\* | sort
policycoreutils-sandbox-2.5-31.el7.x86_64
selinux-policy-3.13.1-245.el7.noarch
selinux-policy-devel-3.13.1-245.el7.noarch
selinux-policy-mls-3.13.1-245.el7.noarch
selinux-policy-sandbox-3.13.1-245.el7.noarch
selinux-policy-targeted-3.13.1-245.el7.noarch
# sesearch -s sandbox_xserver_t -t user_tmp_t -c file -A -C -p write
Found 1 semantic av rules:
allow sandbox_xserver_t user_tmp_t : file { ioctl read write getattr lock append map open } ;
#
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://access.redhat.com/errata/RHBA-2019:2127 |
Description of problem: * SELinux policy contains type transition rules for various sandbox processes which create temporary files in directories labeled tmpfs_t, but similar rules for creating files in directories labeled tmp_t are missing Version-Release number of selected component (if applicable): firefox-60.2.2-1.el7_5.x86_64 policycoreutils-sandbox-2.5-29.el7.x86_64 selinux-policy-sandbox-3.13.1-229.el7_6.5.noarch How reproducible: * always Steps to Reproduce: 1. get a RHEL-7.6 machine 2. log into X session as unconfined user 3. run: sandbox -X firefox Actual results: * firefox does NOT start in sandbox environment ---- type=PROCTITLE msg=audit(11/05/2018 16:22:56.894:1928) : proctitle=/usr/bin/Xephyr -resizeable -title Sandbox sandbox_x_t:s0:c815,c876 -- /usr/bin/firefox -terminate -reset -screen 1000x700 -dp type=SYSCALL msg=audit(11/05/2018 16:22:56.894:1928) : arch=x86_64 syscall=recvmsg success=yes exit=32 a0=0x6 a1=0x7fff6e213770 a2=0x0 a3=0x7fff6e2134a0 items=0 ppid=12675 pid=12684 auid=unconfined-user uid=unconfined-user gid=unconfined-user euid=unconfined-user suid=unconfined-user fsuid=unconfined-user egid=unconfined-user sgid=unconfined-user fsgid=unconfined-user tty=(none) ses=7 comm=Xephyr exe=/usr/bin/Xephyr subj=unconfined_u:unconfined_r:sandbox_xserver_t:s0:c815,c876 key=(null) type=AVC msg=audit(11/05/2018 16:22:56.894:1928) : avc: denied { write } for pid=12684 comm=Xephyr path=/var/tmp/#384275 (deleted) dev="dm-0" ino=384275 scontext=unconfined_u:unconfined_r:sandbox_xserver_t:s0:c815,c876 tcontext=system_u:object_r:user_tmp_t:s0 tclass=file permissive=0 ---- Expected results: * limited firefox starts in sandbox environment Additional info: After loading a custom policy module (just 1 line) the firefox works in enforcing mode: # cat mypolicy.cil ( allow sandbox_xserver_t user_tmp_t ( file ( write ))) # semodule -i mypolicy.cil #