From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757332Ab2CESHf (ORCPT ); Mon, 5 Mar 2012 13:07:35 -0500 Received: from rcsinet15.oracle.com ([148.87.113.117]:25797 "EHLO rcsinet15.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755271Ab2CESHd (ORCPT ); Mon, 5 Mar 2012 13:07:33 -0500 Date: Mon, 5 Mar 2012 21:06:14 +0300 From: Dan Carpenter To: "H. Peter Anvin" Cc: Thomas Gleixner , Ingo Molnar , x86@kernel.org, Matt Fleming , Maarten Lankhorst , linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org Subject: [patch v2] x86, efi: fix pointer math issue in handle_ramdisks() Message-ID: <20120305180614.GA26880@elgon.mountain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20120303075443.GC16816@elte.hu> User-Agent: Mutt/1.5.21 (2010-09-15) X-Source-IP: ucsinet21.oracle.com [156.151.31.93] X-CT-RefId: str=0001.0A090209.4F55009D.0058,ss=1,re=0.000,fgs=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org "filename" is a efi_char16_t string so this check for reaching the end of the array doesn't work. We need to cast the pointer to (u8 *) before doing the math. This patch changes the "filename" to "filename_16" to avoid confusion in the future. Signed-off-by: Dan Carpenter --- v2: Rename "filename" to "filename_16" Also changed cast from (char *) to (u8 *) because it's not a C character string. Ingo suggested (void *) but that's a GCCism I think. diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c index fec216f..0cdfc0d 100644 --- a/arch/x86/boot/compressed/eboot.c +++ b/arch/x86/boot/compressed/eboot.c @@ -539,7 +539,7 @@ static efi_status_t handle_ramdisks(efi_loaded_image_t *image, struct initrd *initrd; efi_file_handle_t *h; efi_file_info_t *info; - efi_char16_t filename[256]; + efi_char16_t filename_16[256]; unsigned long info_sz; efi_guid_t info_guid = EFI_FILE_INFO_ID; efi_char16_t *p; @@ -552,14 +552,14 @@ static efi_status_t handle_ramdisks(efi_loaded_image_t *image, str += 7; initrd = &initrds[i]; - p = filename; + p = filename_16; /* Skip any leading slashes */ while (*str == '/' || *str == '\\') str++; while (*str && *str != ' ' && *str != '\n') { - if (p >= filename + sizeof(filename)) + if ((u8 *)p >= (u8 *)filename_16 + sizeof(filename_16)) break; *p++ = *str++; @@ -583,7 +583,7 @@ static efi_status_t handle_ramdisks(efi_loaded_image_t *image, goto free_initrds; } - status = efi_call_phys5(fh->open, fh, &h, filename, + status = efi_call_phys5(fh->open, fh, &h, filename_16, EFI_FILE_MODE_READ, (u64)0); if (status != EFI_SUCCESS) goto close_handles;