From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:41324 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752465AbeBKEdk (ORCPT ); Sat, 10 Feb 2018 23:33:40 -0500 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Martin K. Petersen" , "Dan Carpenter" Date: Sun, 11 Feb 2018 04:20:06 +0000 Message-ID: Subject: [PATCH 3.2 09/79] scsi: bfa: integer overflow in debugfs In-Reply-To: Sender: stable-owner@vger.kernel.org List-ID: 3.2.99-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Dan Carpenter commit 3e351275655d3c84dc28abf170def9786db5176d upstream. We could allocate less memory than intended because we do: bfad->regdata = kzalloc(len << 2, GFP_KERNEL); The shift can overflow leading to a crash. This is debugfs code so the impact is very small. I fixed the network version of this in March with commit 13e2d5187f6b ("bna: integer overflow bug in debugfs"). Fixes: ab2a9ba189e8 ("[SCSI] bfa: add debugfs support") Signed-off-by: Dan Carpenter Signed-off-by: Martin K. Petersen Signed-off-by: Ben Hutchings --- drivers/scsi/bfa/bfad_debugfs.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/drivers/scsi/bfa/bfad_debugfs.c +++ b/drivers/scsi/bfa/bfad_debugfs.c @@ -276,7 +276,8 @@ bfad_debugfs_write_regrd(struct file *fi struct bfad_s *bfad = port->bfad; struct bfa_s *bfa = &bfad->bfa; struct bfa_ioc_s *ioc = &bfa->ioc; - int addr, len, rc, i; + int addr, rc, i; + u32 len; u32 *regbuf; void __iomem *rb, *reg_addr; unsigned long flags; @@ -296,7 +297,7 @@ bfad_debugfs_write_regrd(struct file *fi } rc = sscanf(kern_buf, "%x:%x", &addr, &len); - if (rc < 2) { + if (rc < 2 || len > (UINT_MAX >> 2)) { printk(KERN_INFO "bfad[%d]: %s failed to read user buf\n", bfad->inst_no, __func__);