Merge tag 'efi-urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/mfleming/efi into x86/urgent

Pull EFI fixes from Matt Fleming:

" - Fix regression in DMI sysfs code for handling "End of Table" entry
    and a type bug that could lead to integer overflow. (Ivan Khoronzhuk)

  - Fix boundary checking in efi_high_alloc() which can lead to memory
    corruption in the EFI boot stubs. (Yinghai Lu)"

Signed-off-by: Ingo Molnar <mingo@kernel.org>

2 files changed, 13 insertions, 12 deletions

diff --git a/drivers/firmware/dmi_scan.c b/drivers/firmware/dmi_scan.c
index c5f7b4e..69fac06 100644
--- a/drivers/firmware/dmi_scan.c
+++ b/drivers/firmware/dmi_scan.c
@@ -78,7 +78,7 @@ static const char * __init dmi_string(const struct dmi_header *dm, u8 s)
  *	We have to be cautious here. We have seen BIOSes with DMI pointers
  *	pointing to completely the wrong place for example
  */
-static void dmi_table(u8 *buf, int len, int num,
+static void dmi_table(u8 *buf, u32 len, int num,
 		      void (*decode)(const struct dmi_header *, void *),
 		      void *private_data)
 {
@@ -93,12 +93,6 @@ static void dmi_table(u8 *buf, int len, int num,
 		const struct dmi_header *dm = (const struct dmi_header *)data;
 
 		/*
-		 * 7.45 End-of-Table (Type 127) [SMBIOS reference spec v3.0.0]
-		 */
-		if (dm->type == DMI_ENTRY_END_OF_TABLE)
-			break;
-
-		/*
 		 *  We want to know the total length (formatted area and
 		 *  strings) before decoding to make sure we won't run off the
 		 *  table in dmi_decode or dmi_string
@@ -108,13 +102,20 @@ static void dmi_table(u8 *buf, int len, int num,
 			data++;
 		if (data - buf < len - 1)
 			decode(dm, private_data);
+
+		/*
+		 * 7.45 End-of-Table (Type 127) [SMBIOS reference spec v3.0.0]
+		 */
+		if (dm->type == DMI_ENTRY_END_OF_TABLE)
+			break;
+
 		data += 2;
 		i++;
 	}
 }
 
 static phys_addr_t dmi_base;
-static u16 dmi_len;
+static u32 dmi_len;
 static u16 dmi_num;
 
 static int __init dmi_walk_early(void (*decode)(const struct dmi_header *,
diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c
index 2fe1950..f07d4a6 100644
--- a/drivers/firmware/efi/libstub/efi-stub-helper.c
+++ b/drivers/firmware/efi/libstub/efi-stub-helper.c
@@ -179,12 +179,12 @@ again:
 		start = desc->phys_addr;
 		end = start + desc->num_pages * (1UL << EFI_PAGE_SHIFT);
 
-		if ((start + size) > end || (start + size) > max)
-			continue;
-
-		if (end - size > max)
+		if (end > max)
 			end = max;
 
+		if ((start + size) > end)
+			continue;
+
 		if (round_down(end - size, align) < start)
 			continue;