From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40510) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dzhz7-00074k-MQ for qemu-devel@nongnu.org; Wed, 04 Oct 2017 07:37:06 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dzhz4-0002Ji-IN for qemu-devel@nongnu.org; Wed, 04 Oct 2017 07:37:05 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58258) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dzhz4-0002Gv-Ax for qemu-devel@nongnu.org; Wed, 04 Oct 2017 07:37:02 -0400 From: P J P Date: Wed, 4 Oct 2017 17:06:52 +0530 Message-Id: <20171004113652.29620-1-ppandit@redhat.com> Subject: [Qemu-devel] [PATCH] 9pfs: use g_malloc0 to allocate space for xattr List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Qemu Developers Cc: Greg Kurz , Tuomas Tynkkynen , Prasad J Pandit From: Prasad J Pandit 9p back-end first queries the size of an extended attribute, allocates space for it via g_malloc() and then retrieves its value into allocated buffer. Race between querying attribute size and retrieving its could lead to memory bytes disclosure. Use g_malloc0() to avoid it. Reported-by: Tuomas Tynkkynen Signed-off-by: Prasad J Pandit --- hw/9pfs/9p.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c index 23ac7bb532..f8bbac251d 100644 --- a/hw/9pfs/9p.c +++ b/hw/9pfs/9p.c @@ -3234,7 +3234,7 @@ static void coroutine_fn v9fs_xattrwalk(void *opaque) xattr_fidp->fid_type = P9_FID_XATTR; xattr_fidp->fs.xattr.xattrwalk_fid = true; if (size) { - xattr_fidp->fs.xattr.value = g_malloc(size); + xattr_fidp->fs.xattr.value = g_malloc0(size); err = v9fs_co_llistxattr(pdu, &xattr_fidp->path, xattr_fidp->fs.xattr.value, xattr_fidp->fs.xattr.len); @@ -3267,7 +3267,7 @@ static void coroutine_fn v9fs_xattrwalk(void *opaque) xattr_fidp->fid_type = P9_FID_XATTR; xattr_fidp->fs.xattr.xattrwalk_fid = true; if (size) { - xattr_fidp->fs.xattr.value = g_malloc(size); + xattr_fidp->fs.xattr.value = g_malloc0(size); err = v9fs_co_lgetxattr(pdu, &xattr_fidp->path, &name, xattr_fidp->fs.xattr.value, xattr_fidp->fs.xattr.len); -- 2.13.6