[PATCH] media: rockchip: rga: Fix possible ERR_PTR dereference in rga_buf_init()

[Alper Ak]

rga_get_frame() can return ERR_PTR(-EINVAL) when buffer type is
unsupported or invalid. rga_buf_init() does not check the return value
and unconditionally dereferences the pointer when accessing f->size.

Add proper ERR_PTR checking and return the error to prevent
dereferencing an invalid pointer.

Fixes: 6040702ade23 ("media: rockchip: rga: allocate DMA descriptors per buffer")
Signed-off-by: Alper Ak <alperyasinak1 at gmail.com>
---
 drivers/media/platform/rockchip/rga/rga-buf.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/media/platform/rockchip/rga/rga-buf.c b/drivers/media/platform/rockchip/rga/rga-buf.c
index 730bdf98565a..bb575873f2b2 100644
--- a/drivers/media/platform/rockchip/rga/rga-buf.c
+++ b/drivers/media/platform/rockchip/rga/rga-buf.c
@@ -80,6 +80,9 @@ static int rga_buf_init(struct vb2_buffer *vb)
 	struct rga_frame *f = rga_get_frame(ctx, vb->vb2_queue->type);
 	size_t n_desc = 0;
 
+	if (IS_ERR(f))
+		return PTR_ERR(f);
+
 	n_desc = DIV_ROUND_UP(f->size, PAGE_SIZE);
 
 	rbuf->n_desc = n_desc;
-- 
2.43.0