ze_t size);
 #endif
 
 #ifdef CONFIG_IMA_SECURE_AND_OR_TRUSTED_BOOT
diff --git a/security/integrity/ima/ima_kexec.c b/security/integrity/ima/ima_kexec.c
index 7362f68f2d8b..8b24e3312ea0 100644
--- a/security/integrity/ima/ima_kexec.c
+++ b/security/integrity/ima/ima_kexec.c
@@ -12,6 +12,8 @@
 #include <linux/kexec.h>
 #include <linux/of.h>
 #include <linux/ima.h>
+#include <linux/mm.h>
+#include <linux/overflow.h>
 #include <linux/reboot.h>
 #include <asm/page.h>
 #include "ima.h"
@@ -296,3 +298,36 @@ void __init ima_load_kexec_buffer(void)
 		pr_debug("Error restoring the measurement list: %d\n", rc);
 	}
 }
+
+/*
+ * ima_validate_range - verify a physical buffer lies in addressable RAM
+ * @phys: physical start address of the buffer from previous kernel
+ * @size: size of the buffer
+ *
+ * On success return 0. On failure returns -EINVAL so callers can skip
+ * restoring.
+ */
+int ima_validate_range(phys_addr_t phys, size_t size)
+{
+	unsigned long start_pfn, end_pfn;
+	phys_addr_t end_phys;
+
+	if (check_add_overflow(phys, (phys_addr_t)size - 1, &end_phys))
+		return -EINVAL;
+
+	start_pfn = PHYS_PFN(phys);
+	end_pfn = PHYS_PFN(end_phys);
+
+#ifdef CONFIG_X86
+	if (!pfn_range_is_mapped(start_pfn, end_pfn))
+#else
+	if (!page_is_ram(start_pfn) || !page_is_ram(end_pfn))
+#endif
+	{
+		pr_warn("IMA: previous kernel measurement buffer %pa (size 0x%zx) lies outside available memory\n",
+			&phys, size);
+		return -EINVAL;
+	}
+
+	return 0;
+}
-- 
2.50.1[PATCH v3 1/3] ima: verify the previous kernel's IMA buffer lies in addressable RAMHarshit Mogalapalli <harshit.m.mogalapalli@oracle.com> undefinedzohar@linux.ibm.com, akpm@linux-foundation.org undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined undefined¨r„ę/