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.
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12 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.
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16 For example:
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18 ps -eZ | grep thumb_t
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23 The thumb_t SELinux type can be entered via the thumb_exec_t file type.
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25 The default entrypoint paths for the thumb_t domain are the following:
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27 /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
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35 SELinux defines process types (domains) for each process running on the
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38 You can see the context of a process using the -Z option to ps
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40 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.
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44 The following process types are defined for thumb:
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46 thumb_t
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48 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.
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61 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.
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66 setsebool -P deny_execmem 1
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70 If you want to allow all unconfined executables to use libraries re‐
71 quiring text relocation that are not labeled textrel_shlib_t, you must
72 turn on the selinuxuser_execmod boolean. Enabled by default.
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74 setsebool -P selinuxuser_execmod 1
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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.
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83 cifs_t
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86 ecryptfs_t
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88 /home/[^/]+/.Private(/.*)?
89 /home/[^/]+/.ecryptfs(/.*)?
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91 fusefs_t
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93 /var/run/user/[0-9]+/gvfs
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95 nfs_t
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100 SELinux requires files to have an extended attribute to define the file
101 type.
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103 You can see the context of a file using the -Z option to ls
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105 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.
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109 STANDARD FILE CONTEXT
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111 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 specify alternate labeling and then use re‐
114 storecon to put the labels on disk.
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116 semanage fcontext -a -t thumb_tmpfs_t '/srv/mythumb_content(/.*)?'
117 restorecon -R -v /srv/mythumb_content
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119 Note: SELinux often uses regular expressions to specify labels that
120 match multiple files.
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122 The following file types are defined for thumb:
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126 thumb_exec_t
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128 - Set files with the thumb_exec_t type, if you want to transition an
129 executable to the thumb_t domain.
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132 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
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142 thumb_home_t
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144 - Set files with the thumb_home_t type, if you want to store thumb
145 files in the users home directory.
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148 Paths:
149 /home/[^/]+/.thumbnails(/.*)?, /home/[^/]+/missfont.log.*,
150 /home/[^/]+/.cache/thumbnails(/.*)?
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153 thumb_tmp_t
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155 - Set files with the thumb_tmp_t type, if you want to store thumb tem‐
156 porary files in the /tmp directories.
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160 thumb_tmpfs_t
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162 - Set files with the thumb_tmpfs_t type, if you want to store thumb
163 files on a tmpfs file system.
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167 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.
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174 semanage fcontext can also be used to manipulate default file context
175 mappings.
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177 semanage permissive can also be used to manipulate whether or not a
178 process type is permissive.
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180 semanage module can also be used to enable/disable/install/remove pol‐
181 icy modules.
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183 semanage boolean can also be used to manipulate the booleans
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186 system-config-selinux is a GUI tool available to customize SELinux pol‐
187 icy settings.
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191 This manual page was auto-generated using sepolicy manpage .
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195 selinux(8), thumb(8), semanage(8), restorecon(8), chcon(1), sepol‐
196 icy(8), setsebool(8)
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200thumb 23-02-03 thumb_selinux(8)