2 files changed, 45 insertions, 14 deletions

diff --git a/drivers/acpi/apei/einj-core.c b/drivers/acpi/apei/einj-core.c
index 2561b045acc7..3c87953dbd19 100644
--- a/drivers/acpi/apei/einj-core.c
+++ b/drivers/acpi/apei/einj-core.c
@@ -656,6 +656,43 @@ static int __einj_error_inject(u32 type, u32 flags, u64 param1, u64 param2,
 	return rc;
 }
 
+/* Allow almost all types of address except MMIO. */
+static bool is_allowed_range(u64 base_addr, u64 size)
+{
+	int i;
+	/*
+	 * MMIO region is usually claimed with IORESOURCE_MEM + IORES_DESC_NONE.
+	 * However, IORES_DESC_NONE is treated like a wildcard when we check if
+	 * region intersects with known resource. So do an allow list check for
+	 * IORES_DESCs that definitely or most likely not MMIO.
+	 */
+	int non_mmio_desc[] = {
+		IORES_DESC_CRASH_KERNEL,
+		IORES_DESC_ACPI_TABLES,
+		IORES_DESC_ACPI_NV_STORAGE,
+		IORES_DESC_PERSISTENT_MEMORY,
+		IORES_DESC_PERSISTENT_MEMORY_LEGACY,
+		/* Treat IORES_DESC_DEVICE_PRIVATE_MEMORY as MMIO. */
+		IORES_DESC_RESERVED,
+		IORES_DESC_SOFT_RESERVED,
+	};
+
+	if (region_intersects(base_addr, size, IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE)
+			      == REGION_INTERSECTS)
+		return true;
+
+	for (i = 0; i < ARRAY_SIZE(non_mmio_desc); ++i) {
+		if (region_intersects(base_addr, size, IORESOURCE_MEM, non_mmio_desc[i])
+				      == REGION_INTERSECTS)
+			return true;
+	}
+
+	if (arch_is_platform_page(base_addr))
+		return true;
+
+	return false;
+}
+
 /* Inject the specified hardware error */
 int einj_error_inject(u32 type, u32 flags, u64 param1, u64 param2, u64 param3,
 		      u64 param4)
@@ -702,19 +739,15 @@ int einj_error_inject(u32 type, u32 flags, u64 param1, u64 param2, u64 param3,
 	 * Disallow crazy address masks that give BIOS leeway to pick
 	 * injection address almost anywhere. Insist on page or
 	 * better granularity and that target address is normal RAM or
-	 * NVDIMM.
+	 * as long as is not MMIO.
 	 */
 	base_addr = param1 & param2;
 	size = ~param2 + 1;
 
-	if (((param2 & PAGE_MASK) != PAGE_MASK) ||
-	    ((region_intersects(base_addr, size, IORESOURCE_SYSTEM_RAM, IORES_DESC_NONE)
-				!= REGION_INTERSECTS) &&
-	     (region_intersects(base_addr, size, IORESOURCE_MEM, IORES_DESC_PERSISTENT_MEMORY)
-				!= REGION_INTERSECTS) &&
-	     (region_intersects(base_addr, size, IORESOURCE_MEM, IORES_DESC_SOFT_RESERVED)
-				!= REGION_INTERSECTS) &&
-	     !arch_is_platform_page(base_addr)))
+	if ((param2 & PAGE_MASK) != PAGE_MASK)
+		return -EINVAL;
+
+	if (!is_allowed_range(base_addr, size))
 		return -EINVAL;
 
 	if (is_zero_pfn(base_addr >> PAGE_SHIFT))
diff --git a/drivers/acpi/apei/erst-dbg.c b/drivers/acpi/apei/erst-dbg.c
index 246076341e8c..ff0e8bf8e97a 100644
--- a/drivers/acpi/apei/erst-dbg.c
+++ b/drivers/acpi/apei/erst-dbg.c
@@ -60,9 +60,8 @@ static long erst_dbg_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
 
 	switch (cmd) {
 	case APEI_ERST_CLEAR_RECORD:
-		rc = copy_from_user(&record_id, (void __user *)arg,
-				    sizeof(record_id));
-		if (rc)
+		if (copy_from_user(&record_id, (void __user *)arg,
+				   sizeof(record_id)))
 			return -EFAULT;
 		return erst_clear(record_id);
 	case APEI_ERST_GET_RECORD_COUNT:
@@ -175,8 +174,7 @@ static ssize_t erst_dbg_write(struct file *filp, const char __user *ubuf,
 		erst_dbg_buf = p;
 		erst_dbg_buf_len = usize;
 	}
-	rc = copy_from_user(erst_dbg_buf, ubuf, usize);
-	if (rc) {
+	if (copy_from_user(erst_dbg_buf, ubuf, usize)) {
 		rc = -EFAULT;
 		goto out;
 	}