ANDROID: binder: fix transaction leak.

If a call to put_user() fails, we failed to
properly free a transaction and send a failed
reply (if necessary).

Bug: 63117588
Test: binderLibTest

Change-Id: Ia98db8cd82ce354a4cdc8811c969988d585c7e31
Signed-off-by: Martijn Coenen <maco@android.com>
This commit is contained in:
Martijn Coenen
2017-08-24 15:23:36 +02:00
committed by Amit Pundir
parent 823e6ab07b
commit b6f477cdc1

View File

@@ -2106,6 +2106,26 @@ static void binder_send_failed_reply(struct binder_transaction *t,
}
}
/**
* binder_cleanup_transaction() - cleans up undelivered transaction
* @t: transaction that needs to be cleaned up
* @reason: reason the transaction wasn't delivered
* @error_code: error to return to caller (if synchronous call)
*/
static void binder_cleanup_transaction(struct binder_transaction *t,
const char *reason,
uint32_t error_code)
{
if (t->buffer->target_node && !(t->flags & TF_ONE_WAY)) {
binder_send_failed_reply(t, error_code);
} else {
binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
"undelivered transaction %d, %s\n",
t->debug_id, reason);
binder_free_transaction(t);
}
}
/**
* binder_validate_object() - checks for a valid metadata object in a buffer.
* @buffer: binder_buffer that we're parsing.
@@ -4188,12 +4208,20 @@ retry:
if (put_user(cmd, (uint32_t __user *)ptr)) {
if (t_from)
binder_thread_dec_tmpref(t_from);
binder_cleanup_transaction(t, "put_user failed",
BR_FAILED_REPLY);
return -EFAULT;
}
ptr += sizeof(uint32_t);
if (copy_to_user(ptr, &tr, sizeof(tr))) {
if (t_from)
binder_thread_dec_tmpref(t_from);
binder_cleanup_transaction(t, "copy_to_user failed",
BR_FAILED_REPLY);
return -EFAULT;
}
ptr += sizeof(tr);
@@ -4263,15 +4291,9 @@ static void binder_release_work(struct binder_proc *proc,
struct binder_transaction *t;
t = container_of(w, struct binder_transaction, work);
if (t->buffer->target_node &&
!(t->flags & TF_ONE_WAY)) {
binder_send_failed_reply(t, BR_DEAD_REPLY);
} else {
binder_debug(BINDER_DEBUG_DEAD_TRANSACTION,
"undelivered transaction %d\n",
t->debug_id);
binder_free_transaction(t);
}
binder_cleanup_transaction(t, "process died.",
BR_DEAD_REPLY);
} break;
case BINDER_WORK_RETURN_ERROR: {
struct binder_error *e = container_of(