From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753319Ab1GIFyp (ORCPT ); Sat, 9 Jul 2011 01:54:45 -0400 Received: from out5.smtp.messagingengine.com ([66.111.4.29]:43052 "EHLO out5.smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752732Ab1GIFyX (ORCPT ); Sat, 9 Jul 2011 01:54:23 -0400 X-Sasl-enc: u5SMnkZqKCqk3O7i8SsZWy464u8yMRzO4dazD+yWWFti 1310190862 X-Mailbox-Line: From gregkh@clark.kroah.org Fri Jul 8 15:51:21 2011 Message-Id: <20110708225121.294321935@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Fri, 08 Jul 2011 15:50:15 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Eric Dumazet , "David S. Miller" Subject: [26/35] inet_diag: fix inet_diag_bc_audit() In-Reply-To: <20110708225343.GA14402@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.32-longterm review patch. If anyone has any objections, please let us know. ------------------ From: Eric Dumazet [ Upstream commit eeb1497277d6b1a0a34ed36b97e18f2bd7d6de0d ] A malicious user or buggy application can inject code and trigger an infinite loop in inet_diag_bc_audit() Also make sure each instruction is aligned on 4 bytes boundary, to avoid unaligned accesses. Reported-by: Dan Rosenberg Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/ipv4/inet_diag.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) --- a/net/ipv4/inet_diag.c +++ b/net/ipv4/inet_diag.c @@ -436,7 +436,7 @@ static int valid_cc(const void *bc, int return 0; if (cc == len) return 1; - if (op->yes < 4) + if (op->yes < 4 || op->yes & 3) return 0; len -= op->yes; bc += op->yes; @@ -446,11 +446,11 @@ static int valid_cc(const void *bc, int static int inet_diag_bc_audit(const void *bytecode, int bytecode_len) { - const unsigned char *bc = bytecode; + const void *bc = bytecode; int len = bytecode_len; while (len > 0) { - struct inet_diag_bc_op *op = (struct inet_diag_bc_op *)bc; + const struct inet_diag_bc_op *op = bc; //printk("BC: %d %d %d {%d} / %d\n", op->code, op->yes, op->no, op[1].no, len); switch (op->code) { @@ -461,22 +461,20 @@ static int inet_diag_bc_audit(const void case INET_DIAG_BC_S_LE: case INET_DIAG_BC_D_GE: case INET_DIAG_BC_D_LE: - if (op->yes < 4 || op->yes > len + 4) - return -EINVAL; case INET_DIAG_BC_JMP: - if (op->no < 4 || op->no > len + 4) + if (op->no < 4 || op->no > len + 4 || op->no & 3) return -EINVAL; if (op->no < len && !valid_cc(bytecode, bytecode_len, len - op->no)) return -EINVAL; break; case INET_DIAG_BC_NOP: - if (op->yes < 4 || op->yes > len + 4) - return -EINVAL; break; default: return -EINVAL; } + if (op->yes < 4 || op->yes > len + 4 || op->yes & 3) + return -EINVAL; bc += op->yes; len -= op->yes; }