misc: fastrpc: Fix ownership reassignment of remote heap

Audio PD daemon will allocate memory for audio PD dynamic loading
usage when it is attaching for the first time to audio PD. As
part of this, the memory ownership is moved to the VM where
audio PD can use it. In case daemon process is killed without any
impact to DSP audio PD, the daemon process will retry to attach to
audio PD and in this case memory won't be reallocated. If the invoke
fails due to any reason, as part of err_invoke, the memory ownership
is getting reassigned to HLOS even when the memory was not allocated.
At this time the audio PD might still be using the memory and an
attemp of ownership reassignment would result in memory issue.

Fixes: 0871561 ("misc: fastrpc: Add support for audiopd")
Cc: stable <stable@kernel.org>
Signed-off-by: Ekansh Gupta <quic_ekangupt@quicinc.com>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Link: https://lore.kernel.org/r/20240628114501.14310-6-srinivas.kandagatla@linaro.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: Ekansh Gupta

drivers/misc/fastrpc.c

@@ -1238,6 +1238,7 @@ static int fastrpc_init_create_static_process(struct fastrpc_user *fl,
 	struct fastrpc_phy_page pages[1];
 	char *name;
 	int err;
+	bool scm_done = false;
 	struct {
 		int pgid;
 		u32 namelen;
@@ -1289,6 +1290,7 @@ static int fastrpc_init_create_static_process(struct fastrpc_user *fl,
 					fl->cctx->remote_heap->phys, fl->cctx->remote_heap->size, err);
 				goto err_map;
 			}
+			scm_done = true;
 		}
 	}
 
@@ -1324,7 +1326,7 @@ static int fastrpc_init_create_static_process(struct fastrpc_user *fl,
 
 	return 0;
 err_invoke:
-	if (fl->cctx->vmcount) {
+	if (fl->cctx->vmcount && scm_done) {
 		u64 src_perms = 0;
 		struct qcom_scm_vmperm dst_perms;
 		u32 i;