spcom: check buf size for send modified command

Check buffer size validity before allocating kernel buffer.

CRs-Fixed: 1094140
Change-Id: I8c280b60f316d7bae87644104d18aa7df4af9efe
Signed-off-by: Amir Samuelov <amirs@codeaurora.org>

1 files changed, 34 insertions, 0 deletions

diff --git a/drivers/soc/qcom/spcom.c b/drivers/soc/qcom/spcom.c
index 0c5f3b84162b..48f11572a92b 100644
--- a/drivers/soc/qcom/spcom.c
+++ b/drivers/soc/qcom/spcom.c
@@ -1407,6 +1407,11 @@ static int modify_ion_addr(void *buf,
 		return -ENODEV;
 	}
 
+	if (buf_size < sizeof(uint64_t)) {
+		pr_err("buf size too small [%d].\n", buf_size);
+		return -ENODEV;
+	}
+
 	if (buf_offset > buf_size - sizeof(uint64_t)) {
 		pr_err("invalid buf_offset [%d].\n", buf_offset);
 		return -ENODEV;
@@ -1469,6 +1474,16 @@ static int spcom_handle_send_modified_command(struct spcom_channel *ch,
 
 	pr_debug("send req/resp ch [%s] size [%d] .\n", ch->name, size);
 
+	/*
+	 * check that cmd buf size is at least struct size,
+	 * to allow access to struct fields.
+	 */
+	if (size < sizeof(*cmd)) {
+		pr_err("ch [%s] invalid cmd buf.\n",
+			ch->name);
+		return -EINVAL;
+	}
+
 	/* Check if remote side connect */
 	if (!spcom_is_channel_connected(ch)) {
 		pr_err("ch [%s] remote side not connect.\n", ch->name);
@@ -1481,6 +1496,18 @@ static int spcom_handle_send_modified_command(struct spcom_channel *ch,
 	timeout_msec = cmd->timeout_msec;
 	memcpy(ion_info, cmd->ion_info, sizeof(ion_info));
 
+	/* Check param validity */
+	if (buf_size > SPCOM_MAX_RESPONSE_SIZE) {
+		pr_err("ch [%s] invalid buf size [%d].\n",
+			ch->name, buf_size);
+		return -EINVAL;
+	}
+	if (size != sizeof(*cmd) + buf_size) {
+		pr_err("ch [%s] invalid cmd size [%d].\n",
+			ch->name, size);
+		return -EINVAL;
+	}
+
 	/* Allocate Buffers*/
 	tx_buf_size = sizeof(*hdr) + buf_size;
 	tx_buf = kzalloc(tx_buf_size, GFP_KERNEL);
@@ -1746,6 +1773,13 @@ static int spcom_handle_read_req_resp(struct spcom_channel *ch,
 		return -ENOTCONN;
 	}
 
+	/* Check param validity */
+	if (size > SPCOM_MAX_RESPONSE_SIZE) {
+		pr_err("ch [%s] inavlid size [%d].\n",
+			ch->name, size);
+		return -EINVAL;
+	}
+
 	/* Allocate Buffers*/
 	rx_buf_size = sizeof(*hdr) + size;
 	rx_buf = kzalloc(rx_buf_size, GFP_KERNEL);