[Skiboot] [PATCH] vpd: Sanitize VPD data

[Vasant Hegde]

On OpenPower system, VPD keyword size tells us the maximum size of the data.
But they fill trailing end with space (0x20) instead of NULL. Also spec
doesn't stop user to have space (0x20) within actual data.

This patch discards trailing spaces before populating device tree.

Reported-by: Pridhiviraj Paidipeddi <ppaidipe at linux.vnet.ibm.com>
Signed-off-by: Vasant Hegde <hegdevasant at linux.vnet.ibm.com>
---
 hdata/vpd.c | 45 ++++++++++++++++++++++++++++++++++++---------
 1 file changed, 36 insertions(+), 9 deletions(-)

diff --git a/hdata/vpd.c b/hdata/vpd.c
index 038569af0..5379a67b4 100644
--- a/hdata/vpd.c
+++ b/hdata/vpd.c
@@ -22,6 +22,7 @@
 #include <device.h>
 #include "hdata.h"
 #include <inttypes.h>
+#include <mem_region-malloc.h>
 
 struct card_info {
 	const char *ccin; 	/* Customer card identification number */
@@ -221,6 +222,32 @@ static const struct card_info *card_info_lookup(char *ccin)
 	return NULL;
 }
 
+/* Discard trailing spaces and populate device tree */
+static struct dt_property *dt_add_prop_sanitize_val(struct dt_node *node,
+			     const char *name, const char *val, int vlen)
+{
+	char *prop = zalloc(vlen + 1);
+	int i;
+	struct dt_property *p = NULL;
+
+	if (!prop)
+		return p;
+
+	memcpy(prop, val, vlen);
+	for (i = vlen - 1; i >= 0; i--) {
+		if (prop[i] != 0x20) {
+			prop[i + 1] = '\0';
+			break;
+		}
+	}
+
+	if (i >= 0)
+		p = dt_add_property_string(node, name, prop);
+
+	free(prop);
+	return p;
+}
+
 /*
  * For OpenPOWER, we only decipher OPFR records. While OP HDAT have VINI
  * records too, populating the fields in there is optional. Also, there
@@ -235,27 +262,27 @@ static void vpd_opfr_parse(struct dt_node *node,
 	/* Vendor Name */
 	kw = vpd_find(fruvpd, fruvpd_sz, "OPFR", "VN", &sz);
 	if (kw)
-		dt_add_property_nstr(node, "vendor", kw, sz);
+		dt_add_prop_sanitize_val(node, "vendor", kw, sz);
 
 	/* FRU Description */
 	kw = vpd_find(fruvpd, fruvpd_sz, "OPFR", "DR", &sz);
 	if (kw)
-		dt_add_property_nstr(node, "description", kw, sz);
+		dt_add_prop_sanitize_val(node, "description", kw, sz);
 
 	/* Part number */
 	kw = vpd_find(fruvpd, fruvpd_sz, "OPFR", "VP", &sz);
 	if (kw)
-		dt_add_property_nstr(node, "part-number", kw, sz);
+		dt_add_prop_sanitize_val(node, "part-number", kw, sz);
 
 	/* Serial number */
 	kw = vpd_find(fruvpd, fruvpd_sz, "OPFR", "VS", &sz);
 	if (kw)
-		dt_add_property_nstr(node, "serial-number", kw, sz);
+		dt_add_prop_sanitize_val(node, "serial-number", kw, sz);
 
 	/* Build date in BCD */
 	kw = vpd_find(fruvpd, fruvpd_sz, "OPFR", "MB", &sz);
 	if (kw)
-		dt_add_property_nstr(node, "build-date", kw, sz);
+		dt_add_prop_sanitize_val(node, "build-date", kw, sz);
 
 	return;
 }
@@ -272,12 +299,12 @@ static void vpd_vrml_parse(struct dt_node *node,
 	/* Part number */
 	kw = vpd_find(fruvpd, fruvpd_sz, "VRML", "PN", &sz);
 	if (kw)
-		dt_add_property_nstr(node, "part-number", kw, sz);
+		dt_add_prop_sanitize_val(node, "part-number", kw, sz);
 
 	/* Serial number */
 	kw = vpd_find(fruvpd, fruvpd_sz, "VRML", "SN", &sz);
 	if (kw)
-		dt_add_property_nstr(node, "serial-number", kw, sz);
+		dt_add_prop_sanitize_val(node, "serial-number", kw, sz);
 
 	return;
 }
@@ -548,13 +575,13 @@ static void sysvpd_parse_opp(const void *sysvpd, unsigned int sysvpd_sz)
 
 	v = vpd_find(sysvpd, sysvpd_sz, "OSYS", "MM", &sz);
 	if (v)
-		dt_add_property_nstr(dt_root, "model", v, sz);
+		dt_add_prop_sanitize_val(dt_root, "model", v, sz);
 	else
 		dt_add_property_string(dt_root, "model", "Unknown");
 
 	v = vpd_find(sysvpd, sysvpd_sz, "OSYS", "SS", &sz);
 	if (v)
-		dt_add_property_nstr(dt_root, "system-id", v, sz);
+		dt_add_prop_sanitize_val(dt_root, "system-id", v, sz);
 	else
 		dt_add_property_string(dt_root, "system-id", "Unknown");
 }
-- 
2.14.3