When the bootloader is UNLOCKED, it should be possible to boot Android
even if AVB reports verification errors [1].

This allows developers to flash modified partitions on
userdebug/engineering builds.

Developers can do so on unlocked devices with:
$ fastboot flash --disable-verity --disable-verification vbmeta vbmeta.img

In such case, bootmeth_android refuses to boot.

Allow the boot to continue when the device is UNLOCKED and AVB reports
verification errors.

[1] 
https://source.android.com/docs/security/features/verifiedboot/boot-flow#unlocked-devices
Fixes: 125d9f3306ea ("bootstd: Add a bootmeth for Android")
Signed-off-by: Mattijs Korpershoek <[email protected]>
---
 boot/bootmeth_android.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/boot/bootmeth_android.c b/boot/bootmeth_android.c
index 
2cd167f80280801618a317a65e93a10e70a0d9ee..564d21784feb0667bf9bed2a59be0a232601a7dd
 100644
--- a/boot/bootmeth_android.c
+++ b/boot/bootmeth_android.c
@@ -407,11 +407,16 @@ static int run_avb_verification(struct bootflow *bflow)
                                 AVB_HASHTREE_ERROR_MODE_RESTART_AND_INVALIDATE,
                                 &out_data);
 
-       if (result != AVB_SLOT_VERIFY_RESULT_OK) {
+       if (result != AVB_SLOT_VERIFY_RESULT_OK && !unlocked) {
                printf("Verification failed, reason: %s\n",
                       str_avb_slot_error(result));
                avb_slot_verify_data_free(out_data);
                return log_msg_ret("avb verify", -EIO);
+       } else if (result != AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION && 
unlocked) {
+               printf("Unlocked verification failed, reason: %s\n",
+                      str_avb_slot_error(result));
+               avb_slot_verify_data_free(out_data);
+               return log_msg_ret("avb verify unlocked", -EIO);
        }
 
        if (unlocked)
@@ -427,9 +432,11 @@ static int run_avb_verification(struct bootflow *bflow)
                        goto free_out_data;
        }
 
-       ret = avb_append_commandline(bflow, out_data->cmdline);
-       if (ret < 0)
-               goto free_out_data;
+       if (result == AVB_SLOT_VERIFY_RESULT_OK) {
+               ret = avb_append_commandline(bflow, out_data->cmdline);
+               if (ret < 0)
+                       goto free_out_data;
+       }
 
        return 0;
 

-- 
2.47.1

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