From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from alt22.smtp-out.videotron.ca ([70.80.0.73]:57990 "EHLO alt22.smtp-out.videotron.ca" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751482AbcGTEUu (ORCPT ); Wed, 20 Jul 2016 00:20:50 -0400 From: Nicolas Pitre To: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Alexander Viro , David Howells , Greg Ungerer Subject: [PATCH v3 08/12] binfmt_flat: use proper user space accessors with old relocs code Date: Wed, 20 Jul 2016 00:20:20 -0400 Message-Id: <1468988424-32671-9-git-send-email-nicolas.pitre@linaro.org> In-Reply-To: <1468988424-32671-1-git-send-email-nicolas.pitre@linaro.org> References: <1468988424-32671-1-git-send-email-nicolas.pitre@linaro.org> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: Signed-off-by: Nicolas Pitre Reviewed-by: Greg Ungerer --- fs/binfmt_flat.c | 30 +++++++++++++++++++----------- 1 file changed, 19 insertions(+), 11 deletions(-) diff --git a/fs/binfmt_flat.c b/fs/binfmt_flat.c index 34f815540e..28fc272d9a 100644 --- a/fs/binfmt_flat.c +++ b/fs/binfmt_flat.c @@ -383,36 +383,39 @@ static void old_reloc(unsigned long rl) { static const char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" }; flat_v2_reloc_t r; - unsigned long *ptr; + unsigned long __user *ptr; + unsigned long val; r.value = rl; #if defined(CONFIG_COLDFIRE) - ptr = (unsigned long *) (current->mm->start_code + r.reloc.offset); + ptr = (unsigned long __user *)(current->mm->start_code + r.reloc.offset); #else - ptr = (unsigned long *) (current->mm->start_data + r.reloc.offset); + ptr = (unsigned long __user *)(current->mm->start_data + r.reloc.offset); #endif + __get_user(val, ptr); pr_debug("Relocation of variable at DATASEG+%x " "(address %p, currently %lx) into segment %s\n", - r.reloc.offset, ptr, *ptr, segment[r.reloc.type]); + r.reloc.offset, ptr, val, segment[r.reloc.type]); switch (r.reloc.type) { case OLD_FLAT_RELOC_TYPE_TEXT: - *ptr += current->mm->start_code; + val += current->mm->start_code; break; case OLD_FLAT_RELOC_TYPE_DATA: - *ptr += current->mm->start_data; + val += current->mm->start_data; break; case OLD_FLAT_RELOC_TYPE_BSS: - *ptr += current->mm->end_data; + val += current->mm->end_data; break; default: pr_err("Unknown relocation type=%x\n", r.reloc.type); break; } + __put_user(val, ptr); - pr_debug("Relocation became %lx\n", *ptr); -} + pr_debug("Relocation became %lx\n", val); +} /****************************************************************************/ @@ -783,8 +786,13 @@ static int load_flat_file(struct linux_binprm * bprm, } } } else { - for (i=0; i < relocs; i++) - old_reloc(ntohl(reloc[i])); + for (i=0; i < relocs; i++) { + unsigned long relval; + if (get_user(relval, reloc + i)) + return -EFAULT; + relval = ntohl(relval); + old_reloc(relval); + } } flush_icache_range(start_code, end_code); -- 2.7.4