| Summary: | SELinux is preventing /usr/sbin/sendmail.postfix from 'use' accesses on the fd /dev/null. | ||
|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Nicolas Mailhot <nicolas.mailhot> |
| Component: | selinux-policy | Assignee: | Miroslav Grepl <mgrepl> |
| Status: | CLOSED RAWHIDE | QA Contact: | Fedora Extras Quality Assurance <extras-qa> |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | rawhide | CC: | dominick.grift, dwalsh, eparis, mgrepl, nicolas.mailhot, sdsmall |
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | x86_64 | ||
| OS: | Linux | ||
| Whiteboard: | setroubleshoot_trace_hash:8c857b2219dc738cfafc684a1e636d3d89125be4ef1d474222e680d2aa4933a7 | ||
| Fixed In Version: | Doc Type: | Bug Fix | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2011-06-17 19:04:39 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
This is another one of those "fd use" access vectors that we may be able to silently deny. Noticed any loss of functionality. ( i guess it is hard to tell since you encountered other similar avc denials some of which were indeed valid ) I have a feeling though that this one can be ignored. This looks like stdin/stdout or stderr was opened to /dev/null and passed to a domain that eventually gets to system_mail_t. Is there any way the kernel could tell us the number of the fd that is being used? IE We probably want to look more closely at FD's being passed that are > 2 I will add init_dontaudit_use_fds to all calls to term_dontaudit_use_* Which will cover this case. Since these terms are being opened by init_t and passed down, this makes sense to me. Fixed in selinux-policy-3.9.16-30.fc16 |
SELinux is preventing /usr/sbin/sendmail.postfix from 'use' accesses on the fd /dev/null. ***** Plugin catchall_boolean (80.5 confidence) suggests ******************* If you want to allow all domains to use other domains file descriptors Then you must tell SELinux about this by enabling the 'allow_domain_fd_use' boolean. Do setsebool -P allow_domain_fd_use 1 ***** Plugin leaks (10.5 confidence) suggests ****************************** If you want to ignore sendmail.postfix trying to use access the null fd, because you believe it should not need this access. Then you should report this as a bug. You can generate a local policy module to dontaudit this access. Do # grep /usr/sbin/sendmail.postfix /var/log/audit/audit.log | audit2allow -D -M mypol # semodule -i mypol.pp ***** Plugin catchall (10.5 confidence) suggests *************************** If you believe that sendmail.postfix should be allowed use access on the null fd by default. Then you should report this as a bug. You can generate a local policy module to allow this access. Do allow this access for now by executing: # grep sendmail /var/log/audit/audit.log | audit2allow -M mypol # semodule -i mypol.pp Additional Information: Source Context system_u:system_r:system_mail_t:s0-s0:c0.c1023 Target Context system_u:system_r:init_t:s0 Target Objects /dev/null [ fd ] Source sendmail Source Path /usr/sbin/sendmail.postfix Port <Inconnu> Host (removed) Source RPM Packages postfix-2.8.3-1.fc16 Target RPM Packages Policy RPM selinux-policy-3.9.16-28.fc16 Selinux Enabled True Policy Type targeted Enforcing Mode Permissive Host Name (removed) Platform Linux (removed) 3.0-0.rc3.git0.3.fc16.x86_64 #1 SMP Tue Jun 14 17:13:27 UTC 2011 x86_64 x86_64 Alert Count 1 First Seen mer. 15 juin 2011 22:15:04 CEST Last Seen mer. 15 juin 2011 22:15:04 CEST Local ID bb2905da-4a6a-44bb-ba89-44a16b02fcdf Raw Audit Messages type=AVC msg=audit(1308168904.535:308): avc: denied { use } for pid=6459 comm="sendmail" path="/dev/null" dev=devtmpfs ino=5052 scontext=system_u:system_r:system_mail_t:s0-s0:c0.c1023 tcontext=system_u:system_r:init_t:s0 tclass=fd type=SYSCALL msg=audit(1308168904.535:308): arch=x86_64 syscall=execve success=yes exit=0 a0=7fff1e1dce60 a1=7fff1e1d9c60 a2=7fff1e21d560 a3=0 items=0 ppid=6434 pid=6459 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=(none) ses=12 comm=sendmail exe=/usr/sbin/sendmail.postfix subj=system_u:system_r:system_mail_t:s0-s0:c0.c1023 key=(null) Hash: sendmail,system_mail_t,init_t,fd,use audit2allow #============= system_mail_t ============== #!!!! This avc can be allowed using the boolean 'allow_domain_fd_use' allow system_mail_t init_t:fd use; audit2allow -R #============= system_mail_t ============== #!!!! This avc can be allowed using the boolean 'allow_domain_fd_use' allow system_mail_t init_t:fd use; Another strange AVC