[3.19.y-ckt stable] Patch "quota: Fix possible GPF due to uninitialised pointers" has been added to the 3.19.y-ckt tree

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    quota: Fix possible GPF due to uninitialised pointers

to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree 
which can be found at:

    http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue

This patch is scheduled to be released in version 3.19.8-ckt18.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.19.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

---8<------------------------------------------------------------

>From 99e03a2006bf9e3d6d6027c21be9e9d848ae430e Mon Sep 17 00:00:00 2001
From: Nikolay Borisov <kernel at kyup.com>
Date: Thu, 3 Mar 2016 10:54:57 +0100
Subject: quota: Fix possible GPF due to uninitialised pointers

commit ab73ef46398e2c0159f3a71de834586422d2a44a upstream.

When dqget() in __dquot_initialize() fails e.g. due to IO error,
__dquot_initialize() will pass an array of uninitialized pointers to
dqput_all() and thus can lead to deference of random data. Fix the
problem by properly initializing the array.

Signed-off-by: Nikolay Borisov <kernel at kyup.com>
Signed-off-by: Jan Kara <jack at suse.cz>
[ kamal: backport to 3.19-stable: context ]
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 fs/quota/dquot.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
index ca035a2..208ffd1 100644
--- a/fs/quota/dquot.c
+++ b/fs/quota/dquot.c
@@ -1389,7 +1389,7 @@ static int dquot_active(const struct inode *inode)
 static void __dquot_initialize(struct inode *inode, int type)
 {
 	int cnt, init_needed = 0;
-	struct dquot *got[MAXQUOTAS];
+	struct dquot *got[MAXQUOTAS] = {};
 	struct super_block *sb = inode->i_sb;
 	qsize_t rsv;

@@ -1399,7 +1399,6 @@ static void __dquot_initialize(struct inode *inode, int type)
 	/* First get references to structures we might need. */
 	for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
 		struct kqid qid;
-		got[cnt] = NULL;
 		if (type != -1 && cnt != type)
 			continue;
 		/*
--
2.7.4