[fastboot] support `erase userdata` as a no-op
A common Android workflow is to pass `-w` to fastboot which triggers an
`erase userdata` command; we can't really support this at the moment
because userdata is nested inside the FVM/super image and gets
automatically erased when we flash that partition, but we've been asked
to ignore this request rather than error out.
Bug: b/322897225
Change-Id: I0ca301c723ae9b5d7057e9b472e0bc1f40b5597d
Reviewed-on: https://turquoise-internal-review.googlesource.com/c/third_party/u-boot/+/803950
Reviewed-by: Yecheng Zhao <zyecheng@google.com>
GitOrigin-RevId: 77d68b2c514684a1848243941640f25453b0ee0f
diff --git a/drivers/usb/gadget/f_fastboot.c b/drivers/usb/gadget/f_fastboot.c
index 301f133..d70b4a2 100644
--- a/drivers/usb/gadget/f_fastboot.c
+++ b/drivers/usb/gadget/f_fastboot.c
@@ -464,8 +464,12 @@
// but is just the FVM.
{ GPT_FVM_NAME, "super", WRITE | ERASE },
{ GPT_DURABLE_BOOT_NAME, "misc", ERASE },
- // Upstream code also aliases userdata -> data and dts -> dtb, but we
- // don't need these at the moment.
+ // `fastboot -w` flag triggers `erase userdata`; functionally this doesn't
+ // apply for Fuchsia since userdata is stored in the FVM and we can't wipe
+ // it separately, so for now we accept `erase userdata` but it's just a
+ // no-op.
+ { "userdata", NULL, ERASE },
+ // Upstream also aliases dts -> dtb, but we don't need this at the moment.
// clang-format on
};
@@ -926,10 +930,6 @@
if (has_boot_slot == 0) {
strncat(response, "ext4", chars_left);
}
- } else if (!strcmp_l1("partition-type:data", cmd)) {
- strncat(response, "ext4", chars_left);
- } else if (!strcmp_l1("partition-type:userdata", cmd)) {
- strncat(response, "ext4", chars_left);
} else if (!strcmp_l1("partition-type:system", cmd)) {
strncat(response, "ext4", chars_left);
} else if (!strcmp_l1("partition-type:vendor", cmd)) {
@@ -1392,6 +1392,19 @@
char* response = response_str;
char *cmd = req->buf;
+ // Set `send_okay` when we've previously sent an INFO response and just want
+ // to finish the command with OKAY.
+ //
+ // Do this first, since in this case we've already parsed the command string
+ // and would fail to find the partition name if we try to do it again here.
+ static int send_okay = 0;
+ if (send_okay) {
+ send_okay = 0;
+ fastboot_okay(NULL);
+ fastboot_tx_write_str(response_str);
+ return;
+ }
+
printf("cmd cb_erase is %s\n", cmd);
const char *part = parse_fb_cmd_partition(cmd);
if (!part) {
@@ -1404,6 +1417,19 @@
return;
}
+ // Special case for "userdata" partition, we just ignore requests to erase
+ // so that `fastboot -w` doesn't error out (b/322897225). In our case
+ // flashing FVM/super automatically wipes userdata.
+ if (strcmp(part, "userdata") == 0) {
+ // This is a bit non-standard so send an INFO message first to alert
+ // users that we're not actually erasing userdata here.
+ fastboot_busy(
+ "erase userdata is a no-op; flash super to wipe userdata");
+ fastboot_tx_write_str(response_str);
+ send_okay = 1;
+ return;
+ }
+
//strcpy(response, "FAILno erase device defined");
if (is_mainstorage_emmc()) {
#ifdef CONFIG_FASTBOOT_FLASH_MMC_DEV
