[PATCH] dmi: Avoid unaligned memory access in save_mem_devices()

[PATCH] dmi: Avoid unaligned memory access in save_mem_devices()

[Luck, Tony]

Firmware is not required to maintain alignment of SMBIOS entries,
so we should take care accessing fields within these structures.
Use "get_unaligned()" to avoid problems.

Signed-off-by: Tony Luck <tony.luck@intel.com>
---

Ingo: belongs on top of the patches already in x86/mce branch
Found on ia64 (which grumbles about unaligned access)

 drivers/firmware/dmi_scan.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/firmware/dmi_scan.c b/drivers/firmware/dmi_scan.c
index 59579a744d58..c7e81ff8f3ef 100644
--- a/drivers/firmware/dmi_scan.c
+++ b/drivers/firmware/dmi_scan.c
@@ -8,6 +8,7 @@
 #include <linux/bootmem.h>
 #include <linux/random.h>
 #include <asm/dmi.h>
+#include <asm/unaligned.h>
 
 /*
  * DMI stands for "Desktop Management Interface".  It is part
@@ -347,7 +348,7 @@ static void __init save_mem_devices(const struct dmi_header *dm, void *v)
 		pr_warn(FW_BUG "Too many DIMM entries in SMBIOS table\n");
 		return;
 	}
-	dmi_memdev[nr].handle = dm->handle;
+	dmi_memdev[nr].handle = get_unaligned(&dm->handle);
 	dmi_memdev[nr].device = dmi_string(dm, d[0x10]);
 	dmi_memdev[nr].bank = dmi_string(dm, d[0x11]);
 	nr++;
-- 
1.8.4.1

[tip:x86/mce] dmi: Avoid unaligned memory access in save_mem_devices()

[tip-bot for Luck, Tony]

Commit-ID:  0841c04d65937ad2808f59c43cb54a92473c8f0e
Gitweb:     http://git.kernel.org/tip/0841c04d65937ad2808f59c43cb54a92473c8f0e
Author:     Luck, Tony <tony.luck@intel.com>
AuthorDate: Fri, 1 Nov 2013 13:59:52 -0700
Committer:  Ingo Molnar <mingo@kernel.org>
CommitDate: Sun, 3 Nov 2013 10:40:12 +0100

dmi: Avoid unaligned memory access in save_mem_devices()

Firmware is not required to maintain alignment of SMBIOS
entries, so we should take care accessing fields within these
structures. Use "get_unaligned()" to avoid problems.

[ Found on ia64 (which grumbles about unaligned access) ]

Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Chen Gong <gong.chen@linux.intel.com>
Link: http://lkml.kernel.org/r/27d82dbff5be1025bf18ab88498632d36c2fcf3c.1383331440.git.tony.luck@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 drivers/firmware/dmi_scan.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/firmware/dmi_scan.c b/drivers/firmware/dmi_scan.c
index 59579a7..c7e81ff 100644
--- a/drivers/firmware/dmi_scan.c
+++ b/drivers/firmware/dmi_scan.c
@@ -8,6 +8,7 @@
 #include <linux/bootmem.h>
 #include <linux/random.h>
 #include <asm/dmi.h>
+#include <asm/unaligned.h>
 
 /*
  * DMI stands for "Desktop Management Interface".  It is part
@@ -347,7 +348,7 @@ static void __init save_mem_devices(const struct dmi_header *dm, void *v)
 		pr_warn(FW_BUG "Too many DIMM entries in SMBIOS table\n");
 		return;
 	}
-	dmi_memdev[nr].handle = dm->handle;
+	dmi_memdev[nr].handle = get_unaligned(&dm->handle);
 	dmi_memdev[nr].device = dmi_string(dm, d[0x10]);
 	dmi_memdev[nr].bank = dmi_string(dm, d[0x11]);
 	nr++;