quota: Fix possible GPF due to uninitialised pointers

Orabug: 23331080

[ Upstream commit ab73ef46398e2c0159f3a71de834586422d2a44a ]

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.

CC: stable@vger.kernel.org
Signed-off-by: Nikolay Borisov <kernel@kyup.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
(cherry picked from commit ab1cc52b3f62f2445c60cbe390d26c50ebc0f3bd)

Signed-off-by: Dan Duval <dan.duval@oracle.com>

diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
index 20d1f74561cf1354b6c5c2d5dabcb8052cf14a73..19c777ad0084993f7c28f243e2f8bfb67f012140 100644 (file)
--- a/fs/quota/dquot.c
+++ b/fs/quota/dquot.c
@@ -1393,7 +1393,7 @@ static int dquot_active(const struct inode *inode)
 static void __dquot_initialize(struct inode *inode, int type)
 {
        int cnt, init_needed = 0;
-       struct dquot **dquots, *got[MAXQUOTAS];
+       struct dquot **dquots, *got[MAXQUOTAS] = {};
        struct super_block *sb = inode->i_sb;
        qsize_t rsv;
 
@@ -1408,7 +1408,6 @@ static void __dquot_initialize(struct inode *inode, int type)
                kprojid_t projid;
                int rc;
 
-               got[cnt] = NULL;
                if (type != -1 && cnt != type)
                        continue;
                /*