GRUB: fix security issue with password auth (integer underflow)

1 files changed, 45 insertions, 0 deletions

diff --git a/resources/grub/patch/secfix/0001-Fix-CVE-2015-8370-Grub2-user-pass-vulnerability.patch b/resources/grub/patch/secfix/0001-Fix-CVE-2015-8370-Grub2-user-pass-vulnerability.patch
new file mode 100644
index 00000000..5701b547
--- /dev/null
+++ b/resources/grub/patch/secfix/0001-Fix-CVE-2015-8370-Grub2-user-pass-vulnerability.patch
@@ -0,0 +1,45 @@
+From 88c9657960a6c5d3673a25c266781e876c181add Mon Sep 17 00:00:00 2001
+From: Hector Marco-Gisbert <hecmargi@upv.es>
+Date: Fri, 13 Nov 2015 16:21:09 +0100
+Subject: [PATCH] Fix security issue when reading username and password
+
+  This patch fixes two integer underflows at:
+    * grub-core/lib/crypto.c
+    * grub-core/normal/auth.c
+
+Signed-off-by: Hector Marco-Gisbert <hecmargi@upv.es>
+Signed-off-by: Ismael Ripoll-Ripoll <iripoll@disca.upv.es>
+---
+ grub-core/lib/crypto.c  | 2 +-
+ grub-core/normal/auth.c | 2 +-
+ 2 files changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/grub-core/lib/crypto.c b/grub-core/lib/crypto.c
+index 010e550..524a3d8 100644
+--- a/grub-core/lib/crypto.c
++++ b/grub-core/lib/crypto.c
+@@ -468,7 +468,7 @@ grub_password_get (char buf[], unsigned buf_size)
+ 	  break;
+ 	}
+ 
+-      if (key == '\b')
++      if (key == '\b' && cur_len)
+ 	{
+ 	  cur_len--;
+ 	  continue;
+diff --git a/grub-core/normal/auth.c b/grub-core/normal/auth.c
+index c6bd96e..5782ec5 100644
+--- a/grub-core/normal/auth.c
++++ b/grub-core/normal/auth.c
+@@ -172,7 +172,7 @@ grub_username_get (char buf[], unsigned buf_size)
+ 	  break;
+ 	}
+ 
+-      if (key == '\b')
++      if (key == '\b' && cur_len)
+ 	{
+ 	  cur_len--;
+ 	  grub_printf ("\b");
+-- 
+1.9.1
+