Bug 2411935
| Summary: | Nemo triggers SELinux alerts with write on io.systemd.DynamicUser when previewing images | ||
|---|---|---|---|
| Product: | [Fedora] Fedora | Reporter: | Eric L. <ewl+redhat> |
| Component: | bubblewrap | Assignee: | Colin Walters <walters> |
| Status: | NEW --- | QA Contact: | Fedora Extras Quality Assurance <extras-qa> |
| Severity: | medium | Docs Contact: | |
| Priority: | unspecified | ||
| Version: | 43 | CC: | alexl, epel-packagers-sig, leigh123linux, mclasen, walters |
| Target Milestone: | --- | Keywords: | Regression |
| Target Release: | --- | ||
| Hardware: | x86_64 | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | Doc Type: | --- | |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | Type: | --- | |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
Why bug nemo with this thumbnailer issue? Reassigning to bubblewrap |
As the subject says, since my upgrade to Fedora 43, opening Nemo in a folder with images triggers a storm of SElinux alerts. Reproducible: Always Steps to Reproduce: 1. open a folder with images in Nemo Actual Results: A storm of SELinux alerts, I count 1612 of them, in the ballpark of one per image previewed: ``` SELinux is preventing blocking-3 from write access on the sock_file io.systemd.DynamicUser. ***** Plugin catchall (100. confidence) suggests ************************** If you believe that blocking-3 should be allowed write access on the io.systemd.DynamicUser sock_file 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: # ausearch -c 'blocking-3' --raw | audit2allow -M my-blocking3 # semodule -X 300 -i my-blocking3.pp Additional Information: Source Context unconfined_u:unconfined_r:thumb_t:s0-s0:c0.c1023 Target Context system_u:object_r:systemd_userdbd_runtime_t:s0 Target Objects io.systemd.DynamicUser [ sock_file ] Source blocking-3 Source Path blocking-3 Port <Unknown> Host REDACTED Source RPM Packages Target RPM Packages SELinux Policy RPM selinux-policy-targeted-42.14-1.fc43.noarch Local Policy RPM selinux-policy-targeted-42.14-1.fc43.noarch Selinux Enabled True Policy Type targeted Enforcing Mode Enforcing Host Name REDACTED Platform Linux REDACTED 6.17.5-300.fc43.x86_64 #1 SMP PREEMPT_DYNAMIC Thu Oct 23 15:35:13 UTC 2025 x86_64 Alert Count 1612 First Seen 2025-11-03 07:56:45 CET Last Seen 2025-11-03 08:08:52 CET Local ID 96888cb3-8bbe-4364-be19-aedf2b02c1c5 Raw Audit Messages type=AVC msg=audit(1762153732.688:1856): avc: denied { write } for pid=35571 comm="blocking-2" name="io.systemd.DynamicUser" dev="tmpfs" ino=1372 scontext=unconfined_u:unconfined_r:thumb_t:s0-s0:c0.c1023 tcontext=system_u:object_r:systemd_userdbd_runtime_t:s0 tclass=sock_file permissive=0 Hash: blocking-3,thumb_t,systemd_userdbd_runtime_t,sock_file,write ``` Expected Results: No SE alerts. It didn't happen with Fedora 42. Additional Information: There are also 3 alerts at the same time cause by bwrap attempting sys_admin access but I don't know if it's related: ``` SELinux is preventing bwrap from sys_admin access on the cap_userns labeled thumb_t. ***** Plugin catchall (100. confidence) suggests ************************** If you believe that bwrap should be allowed sys_admin access on cap_userns labeled thumb_t 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: # ausearch -c 'bwrap' --raw | audit2allow -M my-bwrap # semodule -X 300 -i my-bwrap.pp Additional Information: Source Context unconfined_u:unconfined_r:thumb_t:s0-s0:c0.c1023 Target Context unconfined_u:unconfined_r:thumb_t:s0-s0:c0.c1023 Target Objects Unknown [ cap_userns ] Source bwrap Source Path bwrap Port <Unknown> Host REDACTED Source RPM Packages Target RPM Packages SELinux Policy RPM selinux-policy-targeted-42.14-1.fc43.noarch Local Policy RPM selinux-policy-targeted-42.14-1.fc43.noarch Selinux Enabled True Policy Type targeted Enforcing Mode Enforcing Host Name REDACTED Platform Linux REDACTED 6.17.5-300.fc43.x86_64 #1 SMP PREEMPT_DYNAMIC Thu Oct 23 15:35:13 UTC 2025 x86_64 Alert Count 3 First Seen 2025-11-03 07:56:49 CET Last Seen 2025-11-03 07:56:52 CET Local ID 798943d3-739a-4c75-aea2-3b1d1ece8817 Raw Audit Messages type=AVC msg=audit(1762153012.636:419): avc: denied { sys_admin } for pid=7550 comm="bwrap" capability=21 scontext=unconfined_u:unconfined_r:thumb_t:s0-s0:c0.c1023 tcontext=unconfined_u:unconfined_r:thumb_t:s0-s0:c0.c1023 tclass=cap_userns permissive=0 Hash: bwrap,thumb_t,thumb_t,cap_userns,sys_admin ```