From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jeff Layton , Steve French Subject: [ 25/33] cifs: fix potential buffer overrun when composing a new options string Date: Wed, 5 Jun 2013 13:53:03 -0700 Message-Id: <20130605204708.222895790@linuxfoundation.org> In-Reply-To: <20130605204702.359510786@linuxfoundation.org> References: <20130605204702.359510786@linuxfoundation.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jeff Layton commit 166faf21bd14bc5c5295a44874bf7f3930c30b20 upstream. Consider the case where we have a very short ip= string in the original mount options, and when we chase a referral we end up with a very long IPv6 address. Be sure to allow for that possibility when estimating the size of the string to allocate. Signed-off-by: Jeff Layton Signed-off-by: Steve French Signed-off-by: Greg Kroah-Hartman --- fs/cifs/cifs_dfs_ref.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/fs/cifs/cifs_dfs_ref.c +++ b/fs/cifs/cifs_dfs_ref.c @@ -18,6 +18,7 @@ #include #include #include +#include #include "cifsglob.h" #include "cifsproto.h" #include "cifsfs.h" @@ -149,7 +150,8 @@ char *cifs_compose_mount_options(const c * assuming that we have 'unc=' and 'ip=' in * the original sb_mountdata */ - md_len = strlen(sb_mountdata) + rc + strlen(ref->node_name) + 12; + md_len = strlen(sb_mountdata) + rc + strlen(ref->node_name) + 12 + + INET6_ADDRSTRLEN; mountdata = kzalloc(md_len+1, GFP_KERNEL); if (mountdata == NULL) { rc = -ENOMEM;