From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Lee, Chun-Yi" Subject: [PATCH] x86, efi: initial the local variable of DataSize to zero Date: Thu, 2 May 2013 22:07:01 +0800 Message-ID: <1367503621-13004-1-git-send-email-jlee@suse.com> Return-path: Sender: linux-efi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: matt.fleming-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org, mjg59-1xO5oi07KQx4cg9Nei1l7Q@public.gmane.org Cc: linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, "Lee, Chun-Yi" , Matthew Garrett , "H. Peter Anvin" List-Id: linux-efi@vger.kernel.org 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 Cc: Matt Fleming Cc: H. Peter Anvin Signed-off-by: Lee, Chun-Yi --- 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