1 files changed, 8 insertions, 0 deletions

diff --git a/arch/x86/kernel/e820_64.c b/arch/x86/kernel/e820_64.c
index 151236896243..8e7321101a0a 100644
--- a/arch/x86/kernel/e820_64.c
+++ b/arch/x86/kernel/e820_64.c
@@ -691,6 +691,8 @@ static int __init parse_memmap_opt(char *p)
         mem_size = memparse(p, &p);
         if (p == oldp)
                 return -EINVAL;
+
+        userdef = 1;
         if (*p == '@') {
                 start_at = memparse(p+1, &p);
                 add_memory_region(start_at, mem_size, E820_RAM);
@@ -710,6 +712,12 @@ early_param("memmap", parse_memmap_opt);
 void __init finish_e820_parsing(void)
 {
         if (userdef) {
+                char nr = e820.nr_map;
+
+                if (sanitize_e820_map(e820.map, &nr) < 0)
+                        early_panic("Invalid user supplied memory map");
+                e820.nr_map = nr;
+
                 printk(KERN_INFO "user-defined physical RAM map:\n");
                 e820_print_map("user");
         }