From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Ben Hutchings , Matt Fleming , Kamal Mostafa Subject: [PATCH 141/145] x86/efi: Fix dummy variable buffer allocation Date: Wed, 17 Jul 2013 15:47:53 -0700 Message-Id: <1374101277-7915-142-git-send-email-kamal@canonical.com> In-Reply-To: <1374101277-7915-1-git-send-email-kamal@canonical.com> References: <1374101277-7915-1-git-send-email-kamal@canonical.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.8.13.5 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Ben Hutchings commit b8cb62f82103083a6e8fa5470bfe634a2c06514d upstream. 1. Check for allocation failure 2. Clear the buffer contents, as they may actually be written to flash 3. Don't leak the buffer Compile-tested only. [ Tested successfully on my buggy ASUS machine - Matt ] Signed-off-by: Ben Hutchings Signed-off-by: Matt Fleming Signed-off-by: Kamal Mostafa --- arch/x86/platform/efi/efi.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c index 87e91ba..fe2ac4f 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -1060,7 +1060,10 @@ efi_status_t efi_query_variable_store(u32 attributes, unsigned long size) * that by attempting to use more space than is available. */ unsigned long dummy_size = remaining_size + 1024; - void *dummy = kmalloc(dummy_size, GFP_ATOMIC); + void *dummy = kzalloc(dummy_size, GFP_ATOMIC); + + if (!dummy) + return EFI_OUT_OF_RESOURCES; status = efi.set_variable(efi_dummy_name, &EFI_DUMMY_GUID, EFI_VARIABLE_NON_VOLATILE | @@ -1080,6 +1083,8 @@ efi_status_t efi_query_variable_store(u32 attributes, unsigned long size) 0, dummy); } + kfree(dummy); + /* * The runtime code may now have triggered a garbage collection * run, so check the variable info again -- 1.8.1.2