recovery 升级'@/cache/recovery/block.map' failed错误问题

随着android版本升级，升级包越来越大，当升级包无法存储在cache分区的时候，会把升级包下载到data分区，然后从data分区升级，最近从data分区加载升级包升级的时候，遇到了如下错误：

[    1.945982] Supported API: 3
[    1.957270] charge_status 1, charged 1, status -2, capacity -9223372036854775808
[    1.973917] E:Failed to find CPU thermal info in /sys/class/thermal/
[    1.990514] I:current maximum temperature: -1
[    2.007184] Finding update package...
[    2.057199] I:Update location: @/cache/recovery/block.map
[    2.057251] Opening update package...
[    2.092148] E:Failed to read /cache/recovery/block.map: No such file or directory
[    2.107257] E:Map of '@/cache/recovery/block.map' failed
[    2.140532] E:failed to map file
[    2.158867] I:current maximum temperature: -1
[    2.159049] I:@/cache/recovery/block.map
[    2.159060] I:0
[    2.159072] I:time_total: 0
[    2.159079] I:retry: 0
[    2.159085] I:uncrypt_time: 0
[    2.159092] I:uncrypt_error: 1
[    2.159099] I:
[    2.159108] Installation aborted.
[    2.223841] I:Saving locale "en-US"

最直接的错误信息就是：E:Failed to read /cache/recovery/block.map: No such file or directory

我们根据提示信息，去查询下cache分区，这个block.map文件是否存在。

busybox mount -t ext4 /dev/block/cache /cache （如果无法挂载，设置selinux权限为 permissive）

# busybox ls -l /cache/recovery/
total 104
__bionic_open_tzdata: couldn't find any tzdata when looking for localtime!
__bionic_open_tzdata: couldn't find any tzdata when looking for GMT!
__bionic_open_tzdata: couldn't find any tzdata when looking for posixrules!
-rw-r--r--    1 root     root            85 Jan  1 00:01 last_install
-rw-------    1 system   system       61634 Jan  1 00:01 last_kmsg
-rw-------    1 root     root             5 Jan  1 00:00 last_locale
-rw-r-----    1 root     root         12160 Jan  1 00:01 last_log
-rw-------    1 system   system       12160 Jan  1 00:01 log
-rw-------    1 system   system          24 Jan  1  1970 uncrypt_file
-rw-------    1 root     root            33 Jan  1  1970 uncrypt_status

我们发现，我们需要的/cache/recovery/block.map文件竟然没有，那么肯定是生成block.map的时候出了问题，我们追寻重启进入recovery之前的log信息：

[ 1212.869820@3] type=1400 audit(1209.144:3355): avc: denied { setattr } for pid=4433 comm="Thread-3" name="uncrypt_file" dev="mmcblk0p3" ino=13 scontext=u:r:system_app:s0 tcontext=u:object_r:cache_recovery_file:s0 tclass=file permissive=0
[ 1212.885402@3] type=1400 audit(1212.820:3356): avc: denied { getattr } for pid=4501 comm="uncrypt" path="/data/cache" dev="mmcblk0p17" ino=19 scontext=u:r:uncrypt:s0 tcontext=u:object_r:cache_file:s0 tclass=dir permissive=0
[ 1212.906032@2] watchdogd: watchdogd started (interval 10, margin 20)!
[ 1212.906143@2] watchdogd: Failed to open /dev/watchdog: No such file or directory

好像是处理/data与/cache分区时候遇到了selinux权限问题。（mmcblk0p3mmcblk0p17对应的分别是cache与data分区）

我们可能需要为升级的应用赋予相应的selinux权限，但是上面遇到selinux权限就没有继续了，我们需要知道所有需要的selinux权限，那么我们把selinux设置为 permissive 状态，然后再升级一次，我们观察log状态：

[   98.295965@1] type=1400 audit(84.812:43): avc: denied { open } for pid=2890 comm="HwBinder:2890_1" path="/sys/module/tvin_hdmirx/parameters/en_4k_2_2k" dev="sysfs" ino=6874 scontext=u:r:system_control:s0 tcontext=u:object_r:sysfs_cec:s0 tclass=file permissive=1
[   98.313718@1] type=1400 audit(98.244:44): avc: denied { remove_name } for pid=4076 comm="Thread-4" name="update.zip" dev="mmcblk0p17" ino=316 scontext=u:r:system_app:s0 tcontext=u:object_r:cache_file:s0 tclass=dir permissive=1
[   98.333696@1] type=1400 audit(98.244:44): avc: denied { remove_name } for pid=4076 comm="Thread-4" name="update.zip" dev="mmcblk0p17" ino=316 scontext=u:r:system_app:s0 tcontext=u:object_r:cache_file:s0 tclass=dir permissive=1
[   98.353378@1] type=1400 audit(98.244:45): avc: denied { unlink } for pid=4076 comm="Thread-4" name="update.zip" dev="mmcblk0p17" ino=316 scontext=u:r:system_app:s0 tcontext=u:object_r:cache_file:s0 tclass=file permissive=1
[   98.373096@1] type=1400 audit(98.244:45): avc: denied { unlink } for pid=4076 comm="Thread-4" name="update.zip" dev="mmcblk0p17" ino=316 scontext=u:r:system_app:s0 tcontext=u:object_r:cache_file:s0 tclass=file permissive=1
[   98.392458@1] type=1400 audit(98.304:46): avc: denied { read } for pid=4076 comm="Thread-4" path="/data/cache/update.zip" dev="mmcblk0p17" ino=316 scontext=u:r:system_app:s0 tcontext=u:object_r:cache_file:s0 tclass=file permissive=1
[   98.618368@2] success set parent gpu_p1_composite rate to 500000000
[   99.302385@1] success set parent gpu_p0_composite rate to 400000000
[  100.074360@1] success set parent gpu_p1_composite rate to 285714285
[  101.234329@3] success set parent gpu_p0_composite rate to 125000000
[  101.344037@0] aml_snd_card_tv aml_snd_tv: I2S playback disable
[  101.344244@0] aml_snd_card_tv aml_snd_tv: IEC958 playback disable
[  120.075238@1] type=1400 audit(98.304:46): avc: denied { read } for pid=4076 comm="Thread-4" path="/data/cache/update.zip" dev="mmcblk0p17" ino=316 scontext=u:r:system_app:s0 tcontext=u:object_r:cache_file:s0 tclass=file permissive=1
[  120.090346@1] type=1400 audit(120.024:47): avc: denied { setattr } for pid=4076 comm="Thread-4" name="uncrypt_file" dev="mmcblk0p3" ino=13 scontext=u:r:system_app:s0 tcontext=u:object_r:cache_recovery_file:s0 tclass=file permissive=1
[  121.326417@0] success set parent gpu_p1_composite rate to 666666666
[  121.734307@0] success set parent gpu_p0_composite rate to 500000000
[  121.897440@1] BT_RADIO going: off
[  121.897470@1] BCM_BT: going OFF
[  122.342361@2] success set parent gpu_p1_composite rate to 400000000
[  123.438484@0] success set parent gpu_p0_composite rate to 285714285
[  123.556904@1] type=1400 audit(120.024:47): avc: denied { setattr } for pid=4076 comm="Thread-4" name="uncrypt_file" dev="mmcblk0p3" ino=13 scontext=u:r:system_app:s0 tcontext=u:object_r:cache_recovery_file:s0 tclass=file permissive=1
[  123.572107@1] type=1400 audit(123.508:48): avc: denied { getattr } for pid=4211 comm="uncrypt" path="/data/cache" dev="mmcblk0p17" ino=19 scontext=u:r:uncrypt:s0 tcontext=u:object_r:cache_file:s0 tclass=dir permissive=1
[  123.591568@1] type=1400 audit(123.508:48): avc: denied { getattr } for pid=4211 comm="uncrypt" path="/data/cache" dev="mmcblk0p17" ino=19 scontext=u:r:uncrypt:s0 tcontext=u:object_r:cache_file:s0 tclass=dir permissive=1
[  123.610598@1] type=1400 audit(123.508:49): avc: denied { getattr } for pid=4211 comm="uncrypt" path="/data/cache/update.zip" dev="mmcblk0p17" ino=316 scontext=u:r:uncrypt:s0 tcontext=u:object_r:cache_file:s0 tclass=file permissive=1
[  123.631453@1] type=1400 audit(123.508:49): avc: denied { getattr } for pid=4211 comm="uncrypt" path="/data/cache/update.zip" dev="mmcblk0p17" ino=316 scontext=u:r:uncrypt:s0 tcontext=u:object_r:cache_file:s0 tclass=file permissive=1
[  123.652217@1] type=1400 audit(123.512:50): avc: denied { read } for pid=4211 comm="uncrypt" name="update.zip" dev="mmcblk0p17" ino=316 scontext=u:r:uncrypt:s0 tcontext=u:object_r:cache_file:s0 tclass=file permissive=1
[  123.672583@1] type=1400 audit(123.512:50): avc: denied { read } for pid=4211 comm="uncrypt" name="update.zip" dev="mmcblk0p17" ino=316 scontext=u:r:uncrypt:s0 tcontext=u:object_r:cache_file:s0 tclass=file permissive=1
[  123.689809@1] type=1400 audit(123.512:51): avc: denied { open } for pid=4211 comm="uncrypt" path="/data/cache/update.zip" dev="mmcblk0p17" ino=316 scontext=u:r:uncrypt:s0 tcontext=u:object_r:cache_file:s0 tclass=file permissive=1
[  124.950389@3] success set parent gpu_p1_composite rate to 125000000

我们根据提示信息，增加相应的selinux权限：

diff --git a/common/sepolicy/system_app.te b/common/sepolicy/system_app.te
index 17e7f4e..3c77d47 100644
--- a/common/sepolicy/system_app.te
+++ b/common/sepolicy/system_app.te
@@ -23,8 +23,8 @@
 #allow system_app unlabeled:file { lock open read write getattr };
 #
 ## /cache_file for dvb app creat update.zip file at /cache  dir
-allow system_app cache_file:dir { search add_name write };
-allow system_app cache_file:file { create getattr open write };
+allow system_app cache_file:dir { search add_name remove_name write };
+allow system_app cache_file:file { create getattr open write unlink read };
 #
 #allow system_app log_file:dir { search read open getattr };
 #allow system_app log_file:file { read open getattr };
diff --git a/common/sepolicy/uncrypt.te b/common/sepolicy/uncrypt.te
new file mode 100644
index 0000000..578a6d7
--- /dev/null
+++ b/common/sepolicy/uncrypt.te
@@ -0,0 +1,2 @@
+allow uncrypt cache_file:dir getattr;
+allow uncrypt cache_file:file { open read getattr };

然后就可以正常升级了。至于如何通过提示的avc: denied信息增加selinux权限，可以自行学习。