dcavalca / rpms / grub2

Forked from rpms/grub2 2 years ago
Clone

Blame SOURCES/0480-efi-net-Fix-malformed-device-path-arithmetic-errors-.patch

468bd4
From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
468bd4
From: Thomas Frauendorfer | Miray Software <tf@miray.de>
468bd4
Date: Tue, 4 Aug 2020 17:13:05 +0200
468bd4
Subject: [PATCH] efi/net: Fix malformed device path arithmetic errors in efi
468bd4
 net methods
468bd4
468bd4
---
468bd4
 grub-core/net/efi/net.c | 26 ++++++++++++++++++++------
468bd4
 1 file changed, 20 insertions(+), 6 deletions(-)
468bd4
468bd4
diff --git a/grub-core/net/efi/net.c b/grub-core/net/efi/net.c
468bd4
index 3ae1fbbe3c8..a58c24f6364 100644
468bd4
--- a/grub-core/net/efi/net.c
468bd4
+++ b/grub-core/net/efi/net.c
468bd4
@@ -1318,11 +1318,18 @@ grub_efi_net_boot_from_https (void)
468bd4
 
468bd4
   dp = grub_efi_get_device_path (image->device_handle);
468bd4
 
468bd4
-  while (1)
468bd4
+  while (dp)
468bd4
     {
468bd4
+      grub_efi_uint16_t len = GRUB_EFI_DEVICE_PATH_LENGTH (dp);
468bd4
+      if (len < 4)
468bd4
+      {
468bd4
+	grub_error(GRUB_ERR_OUT_OF_RANGE,
468bd4
+		   "malformed EFI Device Path node has length=%d", len);
468bd4
+	break;
468bd4
+      }
468bd4
+
468bd4
       grub_efi_uint8_t type = GRUB_EFI_DEVICE_PATH_TYPE (dp);
468bd4
       grub_efi_uint8_t subtype = GRUB_EFI_DEVICE_PATH_SUBTYPE (dp);
468bd4
-      grub_efi_uint16_t len = GRUB_EFI_DEVICE_PATH_LENGTH (dp);
468bd4
 
468bd4
       if ((type == GRUB_EFI_MESSAGING_DEVICE_PATH_TYPE)
468bd4
 	  && (subtype == GRUB_EFI_URI_DEVICE_PATH_SUBTYPE))
468bd4
@@ -1335,7 +1342,7 @@ grub_efi_net_boot_from_https (void)
468bd4
 
468bd4
       if (GRUB_EFI_END_ENTIRE_DEVICE_PATH (dp))
468bd4
         break;
468bd4
-      dp = (grub_efi_device_path_t *) ((char *) dp + len);
468bd4
+      dp = GRUB_EFI_NEXT_DEVICE_PATH(dp);
468bd4
     }
468bd4
 
468bd4
   return 0;
468bd4
@@ -1353,11 +1360,18 @@ grub_efi_net_boot_from_opa (void)
468bd4
 
468bd4
   dp = grub_efi_get_device_path (image->device_handle);
468bd4
 
468bd4
-  while (1)
468bd4
+  while (dp)
468bd4
     {
468bd4
+      grub_efi_uint16_t len = GRUB_EFI_DEVICE_PATH_LENGTH (dp);
468bd4
+      if (len < 4)
468bd4
+      {
468bd4
+	grub_error(GRUB_ERR_OUT_OF_RANGE,
468bd4
+		   "malformed EFI Device Path node has length=%d", len);
468bd4
+	break;
468bd4
+      }
468bd4
+
468bd4
       grub_efi_uint8_t type = GRUB_EFI_DEVICE_PATH_TYPE (dp);
468bd4
       grub_efi_uint8_t subtype = GRUB_EFI_DEVICE_PATH_SUBTYPE (dp);
468bd4
-      grub_efi_uint16_t len = GRUB_EFI_DEVICE_PATH_LENGTH (dp);
468bd4
 
468bd4
       if ((type == GRUB_EFI_MESSAGING_DEVICE_PATH_TYPE)
468bd4
 	  && (subtype == GRUB_EFI_MAC_ADDRESS_DEVICE_PATH_SUBTYPE))
468bd4
@@ -1368,7 +1382,7 @@ grub_efi_net_boot_from_opa (void)
468bd4
 
468bd4
       if (GRUB_EFI_END_ENTIRE_DEVICE_PATH (dp))
468bd4
         break;
468bd4
-      dp = (grub_efi_device_path_t *) ((char *) dp + len);
468bd4
+      dp = GRUB_EFI_NEXT_DEVICE_PATH(dp);
468bd4
     }
468bd4
 
468bd4
   return 0;