diff --git a/drivers/acpi/apei/erst.c b/drivers/acpi/apei/erst.c
index 6742f6c68034c5e833505d294902dd97c274c1b0..9bff853e85f37831d8d053a2aa363f139537c9b5 100644
--- a/drivers/acpi/apei/erst.c
+++ b/drivers/acpi/apei/erst.c
@@ -1007,7 +1007,7 @@ static ssize_t erst_reader(struct pstore_record *record)
 	/* The record may be cleared by others, try read next record */
 	if (len == -ENOENT)
 		goto skip;
-	else if (len < sizeof(*rcd)) {
+	else if (len < 0 || len < sizeof(*rcd)) {
 		rc = -EIO;
 		goto out;
 	}