1thumb_selinux(8) SELinux Policy thumb thumb_selinux(8)
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6 thumb_selinux - Security Enhanced Linux Policy for the thumb processes
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9 Security-Enhanced Linux secures the thumb processes via flexible manda‐
10 tory access control.
11 The thumb processes execute with the thumb_t SELinux type. You can
13 check if you have these processes running by executing the ps command
14 with the -Z qualifier.
15 For example:
17 ps -eZ | grep thumb_t
19
23 The thumb_t SELinux type can be entered via the thumb_exec_t file type.
24 The default entrypoint paths for the thumb_t domain are the following:
26 /usr/bin/[^/]*thumbnailer, /usr/bin/gnome-[^/]*-thumbnailer(.sh)?,
28 /usr/lib/tumbler-?[^/]*/tumblerd, /usr/bin/raw-thumbnailer,
29 /usr/bin/ffmpegthumbnailer, /usr/bin/whaaw-thumbnailer,
30 /usr/bin/evince-thumbnailer, /usr/bin/mate-thumbnail-font,
31 /usr/bin/gnome-thumbnail-font, /usr/bin/gsf-office-thumbnailer,
32 /usr/bin/totem-video-thumbnailer, /usr/bin/shotwell-video-thumbnailer
33
35 SELinux defines process types (domains) for each process running on the
36 system
37 You can see the context of a process using the -Z option to ps
39 Policy governs the access confined processes have to files. SELinux
41 thumb policy is very flexible allowing users to setup their thumb pro‐
42 cesses in as secure a method as possible.
43 The following process types are defined for thumb:
45 thumb_t
47 Note: semanage permissive -a thumb_t can be used to make the process
49 type thumb_t permissive. SELinux does not deny access to permissive
50 process types, but the AVC (SELinux denials) messages are still gener‐
51 ated.
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55 SELinux policy is customizable based on least access required. thumb
56 policy is extremely flexible and has several booleans that allow you to
57 manipulate the policy and run thumb with the tightest access possible.
58 If you want to deny user domains applications to map a memory region as
62 both executable and writable, this is dangerous and the executable
63 should be reported in bugzilla, you must turn on the deny_execmem bool‐
64 ean. Enabled by default.
65 setsebool -P deny_execmem 1
67 If you want to allow all unconfined executables to use libraries
71 requiring text relocation that are not labeled textrel_shlib_t, you
72 must turn on the selinuxuser_execmod boolean. Disabled by default.
73 setsebool -P selinuxuser_execmod 1
75
79 The SELinux process type thumb_t can manage files labeled with the fol‐
80 lowing file types. The paths listed are the default paths for these
81 file types. Note the processes UID still need to have DAC permissions.
82 cifs_t
84 ecryptfs_t
87 /home/[^/]+/.Private(/.*)?
89 /home/[^/]+/.ecryptfs(/.*)?
90 fusefs_t
92 /var/run/user/[^/]*/gvfs
94 nfs_t
96
100 SELinux requires files to have an extended attribute to define the file
101 type.
102 You can see the context of a file using the -Z option to ls
104 Policy governs the access confined processes have to these files.
106 SELinux thumb policy is very flexible allowing users to setup their
107 thumb processes in as secure a method as possible.
108 STANDARD FILE CONTEXT
110 SELinux defines the file context types for the thumb, if you wanted to
112 store files with these types in a diffent paths, you need to execute
113 the semanage command to sepecify alternate labeling and then use
114 restorecon to put the labels on disk.
115 semanage fcontext -a -t thumb_tmpfs_t '/srv/mythumb_content(/.*)?'
117 restorecon -R -v /srv/mythumb_content
118 Note: SELinux often uses regular expressions to specify labels that
120 match multiple files.
121 The following file types are defined for thumb:
123 thumb_exec_t
127 - Set files with the thumb_exec_t type, if you want to transition an
129 executable to the thumb_t domain.
130 Paths:
133 /usr/bin/[^/]*thumbnailer, /usr/bin/gnome-[^/]*-thumbnailer(.sh)?,
134 /usr/lib/tumbler-?[^/]*/tumblerd, /usr/bin/raw-thumbnailer,
135 /usr/bin/ffmpegthumbnailer, /usr/bin/whaaw-thumbnailer,
136 /usr/bin/evince-thumbnailer, /usr/bin/mate-thumbnail-font,
137 /usr/bin/gnome-thumbnail-font, /usr/bin/gsf-office-thumbnailer,
138 /usr/bin/totem-video-thumbnailer, /usr/bin/shotwell-video-thumb‐
139 nailer
140 thumb_home_t
143 - Set files with the thumb_home_t type, if you want to store thumb
145 files in the users home directory.
146 Paths:
149 /home/[^/]+/.thumbnails(/.*)?, /home/[^/]+/missfont.log.*,
150 /home/[^/]+/.cache/thumbnails(/.*)?
151 thumb_tmp_t
154 - Set files with the thumb_tmp_t type, if you want to store thumb tem‐
156 porary files in the /tmp directories.
157 thumb_tmpfs_t
161 - Set files with the thumb_tmpfs_t type, if you want to store thumb
163 files on a tmpfs file system.
164 Note: File context can be temporarily modified with the chcon command.
168 If you want to permanently change the file context you need to use the
169 semanage fcontext command. This will modify the SELinux labeling data‐
170 base. You will need to use restorecon to apply the labels.
171
174 semanage fcontext can also be used to manipulate default file context
175 mappings.
176 semanage permissive can also be used to manipulate whether or not a
178 process type is permissive.
179 semanage module can also be used to enable/disable/install/remove pol‐
181 icy modules.
182 semanage boolean can also be used to manipulate the booleans
184 system-config-selinux is a GUI tool available to customize SELinux pol‐
187 icy settings.
188
191 This manual page was auto-generated using sepolicy manpage .
192
195 selinux(8), thumb(8), semanage(8), restorecon(8), chcon(1), sepol‐
196 icy(8), setsebool(8)
197thumb 21-03-26 thumb_selinux(8)