media: vidtv: add error checks

Currently, there are not checks if something gets bad during
memory allocation: it will simply use NULL pointers and
crash.

Add error path at the logic which allocates memory for the
MPEG-TS generator code, propagating the errors up to the
vidtv_bridge. Now, if something wents bad, start_streaming
will return an error that userspace can detect:

	ERROR    DMX_SET_PES_FILTER failed (PID = 0x2000): 12 Cannot allocate memory

and the driver doesn't crash.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

1 files changed, 16 insertions, 3 deletions

diff --git a/drivers/media/test-drivers/vidtv/vidtv_s302m.c b/drivers/media/test-drivers/vidtv/vidtv_s302m.c
index ec88af63a74e..146e4e9d361b 100644
--- a/drivers/media/test-drivers/vidtv/vidtv_s302m.c
+++ b/drivers/media/test-drivers/vidtv/vidtv_s302m.c
@@ -144,7 +144,11 @@ static const struct tone_duration beethoven_5th_symphony[] = {
 
 static struct vidtv_access_unit *vidtv_s302m_access_unit_init(struct vidtv_access_unit *head)
 {
-	struct vidtv_access_unit *au = kzalloc(sizeof(*au), GFP_KERNEL);
+	struct vidtv_access_unit *au;
+
+	au = kzalloc(sizeof(*au), GFP_KERNEL);
+	if (!au)
+		return NULL;
 
 	if (head) {
 		while (head->next)
@@ -441,9 +445,13 @@ static u32 vidtv_s302m_clear(struct vidtv_encoder *e)
 struct vidtv_encoder
 *vidtv_s302m_encoder_init(struct vidtv_s302m_encoder_init_args args)
 {
-	struct vidtv_encoder *e = kzalloc(sizeof(*e), GFP_KERNEL);
+	struct vidtv_encoder *e;
 	u32 priv_sz = sizeof(struct vidtv_s302m_ctx);
-	struct vidtv_s302m_ctx *ctx = kzalloc(priv_sz, GFP_KERNEL);
+	struct vidtv_s302m_ctx *ctx;
+
+	e = kzalloc(sizeof(*e), GFP_KERNEL);
+	if (!e)
+		return NULL;
 
 	e->id = S302M;
 
@@ -461,6 +469,11 @@ struct vidtv_encoder
 	e->src_buf_offset = 0;
 
 	e->is_video_encoder = false;
+
+	ctx = kzalloc(priv_sz, GFP_KERNEL);
+	if (!ctx)
+		return NULL;
+
 	e->ctx = ctx;
 	ctx->last_duration = 0;