Android's native bridge functionality allows an Android native
app written on one CPU architecture to run on a different architecture.
For example, Android ARM apps may run on an x86 CPU.
To support this, the native bridge functionality needs to replace
/proc/cpuinfo with the version from /system/lib/<ISA>/cpuinfo
using a bind mount. See commit ab0da5a9a6860046619629b8e6b83692d35dff86
in system/core.
This change:
1) Creates a new label proc_cpuinfo, and assigns /proc/cpuinfo
that label.
2) Grants read-only access to all SELinux domains, to avoid
breaking pre-existing apps.
3) Grants zygote mounton capabilities for that file, so zygote
can replace the file as necessary.
Addresses the following denial:
avc: denied { mounton } for path="/proc/cpuinfo" dev="proc" ino=4026532012 scontext=u:r:zygote:s0 tcontext=u:object_r:proc:s0 tclass=file
Bug: 17671501
(cherry picked from commit 2de02877a3)
Change-Id: I2c2366bee4fe365288d14bca9778d23a43c368cb
Right now usbfs doesn't have any labels, generating the
following kernel warnings:
<7>[ 3.009582] SELinux: initialized (dev usbfs, type usbfs), not configured for labeling
and the occasional SELinux unlabeled auditallow logs:
<4>[ 285.579254] type=1400 audit(1402010345.094:16): avc: granted { search } for pid=371 comm="qcks" name="/" dev="usbfs" ino=15794 scontext=u:r:kickstart:s0 tcontext=u:object_r:unlabeled:s0 tclass=dir
<4>[ 285.632354] type=1400 audit(1402010345.154:18): avc: granted { search } for pid=371 comm="qcks" name="001" dev="usbfs" ino=15796 scontext=u:r:kickstart:s0 tcontext=u:object_r:unlabeled:s0 tclass=dir
Make sure usbfs is assigned via genfscon
Change-Id: I7191f2584014ba55a3c3a98e7efd0350dc958782
Newer adbd versions use functionfs instead of a custom adb usb gadget.
Make sure the functionfs filesystem is properly labeled, and that adbd
has access to the functionfs files.
Once labeled, this addresses the following denials:
<12>[ 16.127191] type=1400 audit(949060866.189:4): avc: denied { read write } for pid=223 comm="adbd" name="ep0" dev="functionfs" ino=5489 scontext=u:r:adbd:s0 tcontext=u:object_r:functionfs:s0 tclass=file
<12>[ 16.127406] type=1400 audit(949060866.189:5): avc: denied { open } for pid=223 comm="adbd" path="/dev/usb-ffs/adb/ep0" dev="functionfs" ino=5489 scontext=u:r:adbd:s0 tcontext=u:object_r:functionfs:s0 tclass=file
<12>[ 377.366011] type=1400 audit(949061227.419:16): avc: denied { ioctl } for pid=225 comm="adbd" path="/dev/usb-ffs/adb/ep2" dev="functionfs" ino=5564 scontext=u:r:adbd:s0 tcontext=u:object_r:functionfs:s0 tclass=file
Change-Id: Iee8b522e48b4d677fd12f7c83dbc7ffbc9543ad2
pstore(persistent store) have been applied since kernel 3.5
We need to label the pstore-fs in order to use Android with kernel 3.5 or upper version.
My kernel version is 3.10 and I got the below denial log when I ran the "df" command on the adb shell.
type=1400 msg=audit(1388540540.220:18): avc: denied { getattr } for pid=7296 comm="df" name="/" dev="pstore" ino=7703 scontext=u:r:init:s0 tcontext=u:object_r:unlabeled:s0 tclass=filesystem
And the below log is also shown during booting
type=1400 msg=audit(1388539193.750:4): avc: denied { mount } for pid=2844 comm="mount" name="/" dev="pstore" ino=11393 scontext=u:r:init_shell:s0 tcontext=u:object_r:unlabeled:s0 tclass=filesystem
Change-Id: Iaba543d44565c4f20a77a95b9573a628bbd3fd34
/proc/sys/net could use its own type to help distinguish
among some of the proc access rules. Fix dhcp and netd
because of this.
Change-Id: I6e16cba660f07bc25f437bf43e1eba851a88d538
Signed-off-by: rpcraig <rpcraig@tycho.ncsc.mil>
Label /proc/sys/vm/mmap_min_addr with proc_security to prevent
writing it by any domain other than init. Also remove memprotect
mmap_zero permission from unconfineddomain so that it cannot pass
the SELinux check over mapping low memory.
Change-Id: Idc189feeb325a4aea26c93396fd0fa7225e79586
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Limit the ability to write to the files that configure kernel
usermodehelpers and security-sensitive proc settings to the init domain.
Permissive domains can also continue to set these values.
The current list is not exhaustive, just an initial set.
Not all of these files will exist on all kernels/devices.
Controlling access to certain kernel usermodehelpers, e.g. cgroup
release_agent, will require kernel changes to support and cannot be
addressed here.
Expected output on e.g. flo after the change:
ls -Z /sys/kernel/uevent_helper /proc/sys/fs/suid_dumpable /proc/sys/kernel/core_pattern /proc/sys/kernel/dmesg_restrict /proc/sys/kernel/hotplug /proc/sys/kernel/kptr_restrict /proc/sys/kernel/poweroff_cmd /proc/sys/kernel/randomize_va_space /proc/sys/kernel/usermodehelper
-rw-r--r-- root root u:object_r:usermodehelper:s0 uevent_helper
-rw-r--r-- root root u:object_r:proc_security:s0 suid_dumpable
-rw-r--r-- root root u:object_r:usermodehelper:s0 core_pattern
-rw-r--r-- root root u:object_r:proc_security:s0 dmesg_restrict
-rw-r--r-- root root u:object_r:usermodehelper:s0 hotplug
-rw-r--r-- root root u:object_r:proc_security:s0 kptr_restrict
-rw-r--r-- root root u:object_r:usermodehelper:s0 poweroff_cmd
-rw-r--r-- root root u:object_r:proc_security:s0 randomize_va_space
-rw------- root root u:object_r:usermodehelper:s0 bset
-rw------- root root u:object_r:usermodehelper:s0 inheritable
Change-Id: I3f24b4bb90f0916ead863be6afd66d15ac5e8de0
Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
Two new types are introduced:
sdcard_internal
sdcard_external
The existing type of sdcard, is dropped and a new attribute
sdcard_type is introduced.
The boolean app_sdcard_rw has also been changed to allow for
controlling untrusted_app domain to use the internal and external
sdcards.
Change-Id: Ic7252a8e1703a43cb496413809d01cc6cacba8f5
ocontexts was split up into 4 files:
1.fs_use
2.genfs_contexts
3.initial_sid_contexts
4.port_contexts
Each file has their respective declerations in them.
Devices, in their respective device directory, can now specify sepolicy.fs_use, sepolicy.genfs_contexts, sepolicy.port_contexts, and sepolicy.initial_sid_contexts. These declerations will be added right behind their respective sepolicy counterparts in the concatenated configuration file.