From b35b16d2be61943373f16ceb6184a66da84ab229 Mon Sep 17 00:00:00 2001 From: Ben Hutchings Date: Sun, 16 Jun 2013 21:27:12 +0100 Subject: [PATCH] x86/efi: Fix dummy variable buffer allocation 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 --- 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 8ea99d894468..f9537e3044ff 100644 --- a/arch/x86/platform/efi/efi.c +++ b/arch/x86/platform/efi/efi.c @@ -875,7 +875,10 @@ 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 | @@ -895,6 +898,8 @@ 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 -- 2.39.2