From 01b9b0b28626db4a47d7f48744d70abca9914ef1 Mon Sep 17 00:00:00 2001
From: Vasily Averin <vvs@virtuozzo.com>
Date: Thu, 14 Jan 2016 13:41:14 +0300
Subject: [PATCH] cifs_dbg() outputs an uninitialized buffer in cifs_readdir()
In some cases tmp_bug can be not filled in cifs_filldir and stay uninitialized,
therefore its printk with "%s" modifier can leak content of kernelspace memory.
If old content of this buffer does not contain '\0' access bejond end of
allocated object can crash the host.
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Steve French <sfrench@localhost.localdomain>
CC: Stable <stable@vger.kernel.org>
---
fs/cifs/readdir.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/fs/cifs/readdir.c b/fs/cifs/readdir.c
index 0557c45e9c330..b30a4a6d98a0f 100644
--- a/fs/cifs/readdir.c
+++ b/fs/cifs/readdir.c
@@ -847,6 +847,7 @@ int cifs_readdir(struct file *file, struct dir_context *ctx)
* if buggy server returns . and .. late do we want to
* check for that here?
*/
+ *tmp_buf = 0;
rc = cifs_filldir(current_entry, file, ctx,
tmp_buf, max_len);
if (rc) {
--
GitLab