From 49204c116a9ee24536d371be02a2f05e6493c949 Mon Sep 17 00:00:00 2001
From: Antti P Miettinen <amiettinen@nvidia.com>
Date: Thu, 21 Nov 2013 14:32:05 -0800
Subject: [PATCH] block/partitions/efi.c: fix bound check
Use ARRAY_SIZE instead of sizeof to get proper max for label length.
Since this is just a read out of bounds it's not that bad, but the
problem becomes user-visible eg if one tries to use DEBUG_PAGEALLOC and
DEBUG_RODATA, at least with some enhancements from Hiroshi. Of course
the destination array can contain garbage when we read beyond the end of
source array so that would be another user-visible problem.
Signed-off-by: Antti P Miettinen <amiettinen@nvidia.com>
Reviewed-by: Hiroshi Doyu <hdoyu@nvidia.com>
Tested-by: Hiroshi Doyu <hdoyu@nvidia.com>
Cc: Will Drewry <wad@chromium.org>
Cc: Matt Fleming <matt.fleming@intel.com>
Acked-by: Davidlohr Bueso <davidlohr@hp.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
block/partitions/efi.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/block/partitions/efi.c b/block/partitions/efi.c
index a8287b49d0621..dc51f467a5605 100644
--- a/block/partitions/efi.c
+++ b/block/partitions/efi.c
@@ -96,6 +96,7 @@
* - Code works, detects all the partitions.
*
************************************************************/
+#include <linux/kernel.h>
#include <linux/crc32.h>
#include <linux/ctype.h>
#include <linux/math64.h>
@@ -715,8 +716,8 @@ int efi_partition(struct parsed_partitions *state)
efi_guid_unparse(&ptes[i].unique_partition_guid, info->uuid);
/* Naively convert UTF16-LE to 7 bits. */
- label_max = min(sizeof(info->volname) - 1,
- sizeof(ptes[i].partition_name));
+ label_max = min(ARRAY_SIZE(info->volname) - 1,
+ ARRAY_SIZE(ptes[i].partition_name));
info->volname[label_max] = 0;
while (label_count < label_max) {
u8 c = ptes[i].partition_name[label_count] & 0xff;
--
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