cryptfs: kill processes with open files on tmpfs /data
cryptfs will fail to remount /data at boot if any processes (e.g.
dex2oat) have files open on the tmpfs /data partition. Since these
files are about to be destroyed anyway, just kill the offending
processes: first with SIGHUP and finally with SIGKILL.
Also remove a stray i++ that effectively cut the number of retries in
half.
Bug: 17576594
Change-Id: I76fb90ce2e52846ffb9de706e52b7bde98b4186a
Signed-off-by: Greg Hackmann <ghackmann@google.com>
diff --git a/cryptfs.c b/cryptfs.c
index 2878b20..606b9f1 100644
--- a/cryptfs.c
+++ b/cryptfs.c
@@ -1427,26 +1427,38 @@
return encrypt_master_key(passwd, salt, key_buf, master_key, crypt_ftr);
}
-static int wait_and_unmount(char *mountpoint)
+static int wait_and_unmount(char *mountpoint, bool kill)
{
int i, err, rc;
#define WAIT_UNMOUNT_COUNT 20
/* Now umount the tmpfs filesystem */
for (i=0; i<WAIT_UNMOUNT_COUNT; i++) {
- if (umount(mountpoint)) {
- if (errno == EINVAL) {
- /* EINVAL is returned if the directory is not a mountpoint,
- * i.e. there is no filesystem mounted there. So just get out.
- */
- break;
- }
- err = errno;
- sleep(1);
- i++;
- } else {
- break;
+ if (umount(mountpoint) == 0) {
+ break;
}
+
+ if (errno == EINVAL) {
+ /* EINVAL is returned if the directory is not a mountpoint,
+ * i.e. there is no filesystem mounted there. So just get out.
+ */
+ break;
+ }
+
+ err = errno;
+
+ /* If allowed, be increasingly aggressive before the last two retries */
+ if (kill) {
+ if (i == (WAIT_UNMOUNT_COUNT - 3)) {
+ SLOGW("sending SIGHUP to processes with open files\n");
+ vold_killProcessesWithOpenFiles(mountpoint, 1);
+ } else if (i == (WAIT_UNMOUNT_COUNT - 2)) {
+ SLOGW("sending SIGKILL to processes with open files\n");
+ vold_killProcessesWithOpenFiles(mountpoint, 2);
+ }
+ }
+
+ sleep(1);
}
if (i < WAIT_UNMOUNT_COUNT) {
@@ -1588,7 +1600,7 @@
return -1;
}
- if (! (rc = wait_and_unmount(DATA_MNT_POINT)) ) {
+ if (! (rc = wait_and_unmount(DATA_MNT_POINT, true)) ) {
/* If ro.crypto.readonly is set to 1, mount the decrypted
* filesystem readonly. This is used when /data is mounted by
* recovery mode.
@@ -2886,13 +2898,13 @@
* above, so just unmount it now. We must do this _AFTER_ killing the framework,
* unlike the case for vold managed devices above.
*/
- if (wait_and_unmount(sd_mnt_point)) {
+ if (wait_and_unmount(sd_mnt_point, false)) {
goto error_shutting_down;
}
}
/* Now unmount the /data partition. */
- if (wait_and_unmount(DATA_MNT_POINT)) {
+ if (wait_and_unmount(DATA_MNT_POINT, false)) {
if (allow_reboot) {
goto error_shutting_down;
} else {