Define constants for the lengths of the serial number, model number

and firmware revision in the controller's identify structure.

Also modify consumers of these fields to ensure they only use the
specified number of bytes for their respective fields.

Sponsored by:	Intel
Reviewed by:	carl
MFC after:	3 days

2 files changed, 13 insertions, 5 deletions

diff --git a/sys/dev/nvd/nvd.c b/sys/dev/nvd/nvd.c
index 1d2d891..868a238 100644
--- a/sys/dev/nvd/nvd.c
+++ b/sys/dev/nvd/nvd.c
@@ -306,12 +306,16 @@ nvd_new_disk(struct nvme_namespace *ns, void *ctrlr_arg)
 	disk->d_flags |= DISKFLAG_UNMAPPED_BIO;
 #endif
 
+	/*
+	 * d_ident and d_descr are both far bigger than the length of either
+	 *  the serial or model number strings.
+	 */
 	strlcpy(disk->d_ident, nvme_ns_get_serial_number(ns),
-	    sizeof(disk->d_ident));
+	    min(sizeof(disk->d_ident), NVME_SERIAL_NUMBER_LENGTH));
 
 #if __FreeBSD_version >= 900034
 	strlcpy(disk->d_descr, nvme_ns_get_model_number(ns),
-	    sizeof(disk->d_descr));
+	    min(sizeof(disk->d_descr), NVME_MODEL_NUMBER_LENGTH));
 #endif
 
 	disk_create(disk, DISK_VERSION);
diff --git a/sys/dev/nvme/nvme.h b/sys/dev/nvme/nvme.h
index df409cc..f30505a 100644
--- a/sys/dev/nvme/nvme.h
+++ b/sys/dev/nvme/nvme.h
@@ -389,6 +389,10 @@ enum nvme_activate_action {
 	NVME_AA_ACTIVATE			= 0x2,
 };
 
+#define NVME_SERIAL_NUMBER_LENGTH	20
+#define NVME_MODEL_NUMBER_LENGTH	40
+#define NVME_FIRMWARE_REVISION_LENGTH	8
+
 struct nvme_controller_data {
 
 	/* bytes 0-255: controller capabilities and features */
@@ -400,13 +404,13 @@ struct nvme_controller_data {
 	uint16_t		ssvid;
 
 	/** serial number */
-	int8_t			sn[20];
+	int8_t			sn[NVME_SERIAL_NUMBER_LENGTH];
 
 	/** model number */
-	int8_t			mn[40];
+	int8_t			mn[NVME_MODEL_NUMBER_LENGTH];
 
 	/** firmware revision */
-	uint8_t			fr[8];
+	uint8_t			fr[NVME_FIRMWARE_REVISION_LENGTH];
 
 	/** recommended arbitration burst */
 	uint8_t			rab;