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From:   Jiasheng Jiang <jiasheng@iscas.ac.cn>
To:     dwlsalmeida@gmail.com, mchehab@kernel.org
Cc:     linux-media@vger.kernel.org, linux-kernel@vger.kernel.org,
        Jiasheng Jiang <jiasheng@iscas.ac.cn>
Subject: [PATCH 1/2] media: vidtv: psi: Add check for kstrdup
Date:   Mon, 19 Jun 2023 16:12:01 +0800
Message-Id: <20230619081202.25283-1-jiasheng@iscas.ac.cn>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Add check for the return value of kstrdup() and return the error
if it fails in order to avoid NULL pointer dereference.

Fixes: 7a7899f6f58e ("media: vidtv: psi: Implement an Event Information Table (EIT)")
Fixes: c2f78f0cb294 ("media: vidtv: psi: add a Network Information Table (NIT)")
Fixes: f90cf6079bf6 ("media: vidtv: add a bridge driver")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
---
 drivers/media/test-drivers/vidtv/vidtv_psi.c | 45 +++++++++++++++++---
 1 file changed, 40 insertions(+), 5 deletions(-)

diff --git a/drivers/media/test-drivers/vidtv/vidtv_psi.c b/drivers/media/test-drivers/vidtv/vidtv_psi.c
index ce0b7a6e92dc..2a51c898c11e 100644
--- a/drivers/media/test-drivers/vidtv/vidtv_psi.c
+++ b/drivers/media/test-drivers/vidtv/vidtv_psi.c
@@ -301,16 +301,29 @@ struct vidtv_psi_desc_service *vidtv_psi_service_desc_init(struct vidtv_psi_desc
 
 	desc->service_name_len = service_name_len;
 
-	if (service_name && service_name_len)
+	if (service_name && service_name_len) {
 		desc->service_name = kstrdup(service_name, GFP_KERNEL);
+		if (!desc->service_name)
+			goto free_desc;
+	}
 
 	desc->provider_name_len = provider_name_len;
 
-	if (provider_name && provider_name_len)
+	if (provider_name && provider_name_len) {
 		desc->provider_name = kstrdup(provider_name, GFP_KERNEL);
+		if (!desc->provider_name)
+			goto free_desc_service_name;
+	}
 
 	vidtv_psi_desc_chain(head, (struct vidtv_psi_desc *)desc);
 	return desc;
+
+free_desc_service_name:
+	if (service_name && service_name_len)
+		kfree(desc->service_name);
+free_desc:
+	kfree(desc);
+	return NULL;
 }
 
 struct vidtv_psi_desc_registration
@@ -355,8 +368,13 @@ struct vidtv_psi_desc_network_name
 
 	desc->length = network_name_len;
 
-	if (network_name && network_name_len)
+	if (network_name && network_name_len) {
 		desc->network_name = kstrdup(network_name, GFP_KERNEL);
+		if (!desc->network_name) {
+			kfree(desc);
+			return NULL;
+		}
+	}
 
 	vidtv_psi_desc_chain(head, (struct vidtv_psi_desc *)desc);
 	return desc;
@@ -442,15 +460,32 @@ struct vidtv_psi_desc_short_event
 		iso_language_code = "eng";
 
 	desc->iso_language_code = kstrdup(iso_language_code, GFP_KERNEL);
+	if (!desc->iso_language_code)
+		goto free_desc;
 
-	if (event_name && event_name_len)
+	if (event_name && event_name_len) {
 		desc->event_name = kstrdup(event_name, GFP_KERNEL);
+		if (!desc->event_name)
+			goto free_desc_language_code;
+	}
 
-	if (text && text_len)
+	if (text && text_len) {
 		desc->text = kstrdup(text, GFP_KERNEL);
+		if (!desc->text)
+			goto free_desc_event_name;
+	}
 
 	vidtv_psi_desc_chain(head, (struct vidtv_psi_desc *)desc);
 	return desc;
+
+free_desc_event_name:
+	if (event_name && event_name_len)
+		kfree(desc->event_name);
+free_desc_language_code:
+	kfree(desc->iso_language_code);
+free_desc:
+	kfree(desc);
+	return NULL;
 }
 
 struct vidtv_psi_desc *vidtv_psi_desc_clone(struct vidtv_psi_desc *desc)
-- 
2.25.1