platform/x86/amd/hsmp: Ensure sock->metric_tbl_addr is non-NULL

[ Upstream commit 2c78fb2 ]

If metric table address is not allocated, accessing metrics_bin will
result in a NULL pointer dereference, so add a check.

Fixes: 5150542 ("platform/x86/amd/hsmp: add support for metrics tbl")
Signed-off-by: Suma Hegde <suma.hegde@amd.com>
Link: https://lore.kernel.org/r/20250807100637.952729-1-suma.hegde@amd.com
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: sumachidanand

drivers/platform/x86/amd/hsmp/hsmp.c

@@ -356,6 +356,11 @@ ssize_t hsmp_metric_tbl_read(struct hsmp_socket *sock, char *buf, size_t size)
 	if (!sock || !buf)
 		return -EINVAL;
 
+	if (!sock->metric_tbl_addr) {
+		dev_err(sock->dev, "Metrics table address not available\n");
+		return -ENOMEM;
+	}
+
 	/* Do not support lseek(), also don't allow more than the size of metric table */
 	if (size != sizeof(struct hsmp_metric_table)) {
 		dev_err(sock->dev, "Wrong buffer size\n");