From: Kulikov Vasiliy <segooon@gmail.com>
Date: Sat, 30 Oct 2010 14:26:17 +0000 (+0000)
Subject: xfs: xfs_ioctl: fix information leak to userland
X-Git-Tag: firefly_0821_release~7613^2~3456^2~6
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=6762b938eac878a30a90e770ac655874c36bc642;p=firefly-linux-kernel-4.4.55.git

xfs: xfs_ioctl: fix information leak to userland

al_hreq is copied from userland.  If al_hreq.buflen is not properly aligned
then xfs_attr_list will ignore the last bytes of kbuf.  These bytes are
unitialized.  It leads to leaking of contents of kernel stack memory.

Signed-off-by: Vasiliy Kulikov <segooon@gmail.com>
Signed-off-by: Alex Elder <aelder@sgi.com>
---

diff --git a/fs/xfs/linux-2.6/xfs_ioctl.c b/fs/xfs/linux-2.6/xfs_ioctl.c
index 2ea238f6d38e..ad442d9e392e 100644
--- a/fs/xfs/linux-2.6/xfs_ioctl.c
+++ b/fs/xfs/linux-2.6/xfs_ioctl.c
@@ -416,7 +416,7 @@ xfs_attrlist_by_handle(
 	if (IS_ERR(dentry))
 		return PTR_ERR(dentry);
 
-	kbuf = kmalloc(al_hreq.buflen, GFP_KERNEL);
+	kbuf = kzalloc(al_hreq.buflen, GFP_KERNEL);
 	if (!kbuf)
 		goto out_dput;