From: Julien Grall <julien.grall@arm.com>
Date: Thu, 4 May 2017 19:36:41 +0000 (+0100)
Subject: xen/arm: efi: Avoid out-of-bounds write in meminfo_add_bank
X-Git-Tag: 4.9.0-rc4~10
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=a68ffd36e9eae8db318c5752f5319d2901ef74b3;p=xen.git

xen/arm: efi: Avoid out-of-bounds write in meminfo_add_bank

Commit 2c77db77 "xen/arm: efi: Avoid duplicating the addition of a new
bank", introduced a new function meminfo_add_bank that add a new bank.
This new code fails to check correctly the size of the array which may
result to an out-of-bounds write.

Coverity-ID: 1433183
Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
---

diff --git a/xen/arch/arm/efi/efi-boot.h b/xen/arch/arm/efi/efi-boot.h
index e1e447ac8e..2986c83447 100644
--- a/xen/arch/arm/efi/efi-boot.h
+++ b/xen/arch/arm/efi/efi-boot.h
@@ -128,7 +128,7 @@ static bool __init meminfo_add_bank(struct meminfo *mem,
 {
     struct membank *bank;
 
-    if ( mem->nr_banks > NR_MEM_BANKS )
+    if ( mem->nr_banks >= NR_MEM_BANKS )
         return false;
 
     bank = &mem->bank[mem->nr_banks];