Merge tag 'dmi-for-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging

Pull dmi updates from Jean Delvare:
 "Bug fixes:

   - KCFI violation in dmi-id

   - stop decoding on broken (short) DMI table entry

  New features:

   - print info about populated memory slots at boot"

* tag 'dmi-for-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging:
  firmware: dmi: Add info message for number of populated and total memory slots
  firmware: dmi: Stop decoding on broken entry
  firmware: dmi-id: add a release callback function

2 files changed, 23 insertions, 1 deletions

diff --git a/drivers/firmware/dmi-id.c b/drivers/firmware/dmi-id.c
index 5f3a3e913d28..d19c78a78ae3 100644
--- a/drivers/firmware/dmi-id.c
+++ b/drivers/firmware/dmi-id.c
@@ -169,9 +169,14 @@ static int dmi_dev_uevent(const struct device *dev, struct kobj_uevent_env *env)
 	return 0;
 }
 
+static void dmi_dev_release(struct device *dev)
+{
+	kfree(dev);
+}
+
 static struct class dmi_class = {
 	.name = "dmi",
-	.dev_release = (void(*)(struct device *)) kfree,
+	.dev_release = dmi_dev_release,
 	.dev_uevent = dmi_dev_uevent,
 };
 
diff --git a/drivers/firmware/dmi_scan.c b/drivers/firmware/dmi_scan.c
index 015c95a825d3..68231c638c55 100644
--- a/drivers/firmware/dmi_scan.c
+++ b/drivers/firmware/dmi_scan.c
@@ -42,6 +42,7 @@ static struct dmi_memdev_info {
 	u8 type;		/* DDR2, DDR3, DDR4 etc */
 } *dmi_memdev;
 static int dmi_memdev_nr;
+static int dmi_memdev_populated_nr __initdata;
 
 static const char * __init dmi_string_nosave(const struct dmi_header *dm, u8 s)
 {
@@ -102,6 +103,17 @@ static void dmi_decode_table(u8 *buf,
 		const struct dmi_header *dm = (const struct dmi_header *)data;
 
 		/*
+		 * If a short entry is found (less than 4 bytes), not only it
+		 * is invalid, but we cannot reliably locate the next entry.
+		 */
+		if (dm->length < sizeof(struct dmi_header)) {
+			pr_warn(FW_BUG
+				"Corrupted DMI table, offset %zd (only %d entries processed)\n",
+				data - buf, i);
+			break;
+		}
+
+		/*
 		 *  We want to know the total length (formatted area and
 		 *  strings) before decoding to make sure we won't run off the
 		 *  table in dmi_decode or dmi_string
@@ -448,6 +460,9 @@ static void __init save_mem_devices(const struct dmi_header *dm, void *v)
 	else
 		bytes = (u64)get_unaligned((u32 *)&d[0x1C]) << 20;
 
+	if (bytes)
+		dmi_memdev_populated_nr++;
+
 	dmi_memdev[nr].size = bytes;
 	nr++;
 }
@@ -824,6 +839,8 @@ void __init dmi_setup(void)
 		return;
 
 	dmi_memdev_walk();
+	pr_info("DMI: Memory slots populated: %d/%d\n",
+		dmi_memdev_populated_nr, dmi_memdev_nr);
 	dump_stack_set_arch_desc("%s", dmi_ids_string);
 }