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@kyup.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/quota/dquot.c b/fs/quota/dquot.c
index 3c3b81bb6dfebbd3d6c3f1f8f1252e46308bf9c9..850d17fa0aa382c0995fddf7710d659df88abf60 100644 (file)
--- a/fs/quota/dquot.c
+++ b/fs/quota/dquot.c
@@ -1398,7 +1398,7 @@ static int dquot_active(const struct inode *inode)
 static int __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;
        int ret = 0;
@@ -1415,7 +1415,6 @@ static int __dquot_initialize(struct inode *inode, int type)
                int rc;
                struct dquot *dquot;
 
-               got[cnt] = NULL;
                if (type != -1 && cnt != type)
                        continue;
                /*