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* [PATCH] x86, efi: initial the local variable of DataSize to zero
@ 2013-04-26 17:19 Lee, Chun-Yi
  2013-04-29  9:55 ` Matt Fleming
  2013-04-29 10:25 ` joeyli
  0 siblings, 2 replies; 6+ messages in thread
From: Lee, Chun-Yi @ 2013-04-26 17:19 UTC (permalink / raw)
  To: matt.fleming, mjg59
  Cc: linux-efi, linux-kernel, Lee, Chun-Yi, Matthew Garrett,
	H. Peter Anvin

That will be better initial the value of DataSize to zero for the input of
GetVariable(), otherwise we will feed a random value. The debug log of input
DataSize like this:

...
[  195.915612] EFI Variables Facility v0.08 2004-May-17
[  195.915819] efi: size: 18446744071581821342
[  195.915969] efi:  size': 18446744071581821342
[  195.916324] efi: size: 18446612150714306560
[  195.916632] efi:  size': 18446612150714306560
[  195.917159] efi: size: 18446612150714306560
[  195.917453] efi:  size': 18446612150714306560
...

Found on Acer Aspire V3 BIOS, it will not return the size of data if we input a
non-zero DataSize.

Cc: Matthew Garrett <mjg@redhat.com>
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Lee, Chun-Yi <jlee@suse.com>
---
 arch/x86/platform/efi/efi.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index e4a86a6..cb59732 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -204,7 +204,7 @@ static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
 	}
 
 	if (boot_used_size && !finished) {
-		unsigned long size;
+		unsigned long size = 0;
 		u32 attr;
 		efi_status_t s;
 		void *tmp;
-- 
1.6.0.2


^ permalink raw reply related	[flat|nested] 6+ messages in thread
* [PATCH] x86, efi: initial the local variable of DataSize to zero
@ 2013-05-02 14:07 Lee, Chun-Yi
  2013-05-03  8:50 ` Matt Fleming
  0 siblings, 1 reply; 6+ messages in thread
From: Lee, Chun-Yi @ 2013-05-02 14:07 UTC (permalink / raw)
  To: matt.fleming, mjg59
  Cc: linux-efi, linux-kernel, Lee, Chun-Yi, Matthew Garrett,
	H. Peter Anvin

That will be better initial the value of DataSize to zero for the input of
GetVariable(), otherwise we will feed a random value. The debug log of input
DataSize like this:

...
[  195.915612] EFI Variables Facility v0.08 2004-May-17
[  195.915819] efi: size: 18446744071581821342
[  195.915969] efi:  size': 18446744071581821342
[  195.916324] efi: size: 18446612150714306560
[  195.916632] efi:  size': 18446612150714306560
[  195.917159] efi: size: 18446612150714306560
[  195.917453] efi:  size': 18446612150714306560
...

The size' is value that was returned by BIOS.

After applied this patch:
[   82.442042] EFI Variables Facility v0.08 2004-May-17
[   82.442202] efi: size: 0
[   82.442360] efi:  size': 1039
[   82.443828] efi: size: 0
[   82.444127] efi:  size': 2616
[   82.447057] efi: size: 0
[   82.447356] efi:  size': 5832
...

Found on Acer Aspire V3 BIOS, it will not return the size of data if we input a
non-zero DataSize.

Cc: Matthew Garrett <mjg@redhat.com>
Cc: Matt Fleming <matt.fleming@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Lee, Chun-Yi <jlee@suse.com>
---
 arch/x86/platform/efi/efi.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
index e4a86a6..cb59732 100644
--- a/arch/x86/platform/efi/efi.c
+++ b/arch/x86/platform/efi/efi.c
@@ -204,7 +204,7 @@ static efi_status_t virt_efi_get_next_variable(unsigned long *name_size,
 	}
 
 	if (boot_used_size && !finished) {
-		unsigned long size;
+		unsigned long size = 0;
 		u32 attr;
 		efi_status_t s;
 		void *tmp;
-- 
1.6.0.2


^ permalink raw reply related	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2013-05-03  8:50 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
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2013-04-26 17:19 [PATCH] x86, efi: initial the local variable of DataSize to zero Lee, Chun-Yi
2013-04-29  9:55 ` Matt Fleming
2013-04-29 10:25 ` joeyli
2013-04-29 10:34   ` joeyli
  -- strict thread matches above, loose matches on Subject: below --
2013-05-02 14:07 Lee, Chun-Yi
2013-05-03  8:50 ` Matt Fleming

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