Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755933AbaBEUxE (ORCPT ); Wed, 5 Feb 2014 15:53:04 -0500 Received: from mail1.windriver.com ([147.11.146.13]:48228 "EHLO mail1.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754709AbaBEUFz (ORCPT ); Wed, 5 Feb 2014 15:05:55 -0500 From: Paul Gortmaker To: , CC: Denys Vlasenko , Oleg Nesterov , Venu Byravarasu , Andrew Morton , Paul Gortmaker Subject: [v2.6.34-stable 090/213] coredump: prevent double-free on an error path in core dumper Date: Wed, 5 Feb 2014 15:00:45 -0500 Message-ID: <1391630568-49251-91-git-send-email-paul.gortmaker@windriver.com> X-Mailer: git-send-email 1.8.5.2 In-Reply-To: <1391630568-49251-1-git-send-email-paul.gortmaker@windriver.com> References: <1391630568-49251-1-git-send-email-paul.gortmaker@windriver.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Denys Vlasenko ------------------- This is a commit scheduled for the next v2.6.34 longterm release. http://git.kernel.org/?p=linux/kernel/git/paulg/longterm-queue-2.6.34.git If you see a problem with using this for longterm, please comment. ------------------- commit f34f9d186df35e5c39163444c43b4fc6255e39c5 upstream. In !CORE_DUMP_USE_REGSET case, if elf_note_info_init fails to allocate memory for info->fields, it frees already allocated stuff and returns error to its caller, fill_note_info. Which in turn returns error to its caller, elf_core_dump. Which jumps to cleanup label and calls free_note_info, which will happily try to free all info->fields again. BOOM. This is the fix. Signed-off-by: Oleg Nesterov Signed-off-by: Denys Vlasenko Cc: Venu Byravarasu Signed-off-by: Andrew Morton Signed-off-by: Paul Gortmaker --- fs/binfmt_elf.c | 19 ++++--------------- 1 file changed, 4 insertions(+), 15 deletions(-) diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c index c21da8aebe46..eee4dd5a13cc 100644 --- a/fs/binfmt_elf.c +++ b/fs/binfmt_elf.c @@ -1661,30 +1661,19 @@ static int elf_note_info_init(struct elf_note_info *info) return 0; info->psinfo = kmalloc(sizeof(*info->psinfo), GFP_KERNEL); if (!info->psinfo) - goto notes_free; + return 0; info->prstatus = kmalloc(sizeof(*info->prstatus), GFP_KERNEL); if (!info->prstatus) - goto psinfo_free; + return 0; info->fpu = kmalloc(sizeof(*info->fpu), GFP_KERNEL); if (!info->fpu) - goto prstatus_free; + return 0; #ifdef ELF_CORE_COPY_XFPREGS info->xfpu = kmalloc(sizeof(*info->xfpu), GFP_KERNEL); if (!info->xfpu) - goto fpu_free; + return 0; #endif return 1; -#ifdef ELF_CORE_COPY_XFPREGS - fpu_free: - kfree(info->fpu); -#endif - prstatus_free: - kfree(info->prstatus); - psinfo_free: - kfree(info->psinfo); - notes_free: - kfree(info->notes); - return 0; } static int fill_note_info(struct elfhdr *elf, int phdrs, -- 1.8.5.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/