From aed9eb1b21e85a846c805bc299bbb9d039d4a95b Mon Sep 17 00:00:00 2001 From: Colin Ian King Date: Tue, 5 Sep 2017 17:51:23 +0100 Subject: ext4: fix null pointer dereference on sbi In the case of a kzalloc failure when allocating sbi we end up with a null pointer dereference on sbi when assigning sbi->s_daxdev. Fix this by moving the assignment of sbi->s_daxdev to after the null pointer check of sbi. Detected by CoverityScan CID#1455379 ("Dereference before null check") Fixes: 5e405595e5bf ("ext4: perform dax_device lookup at mount") Signed-off-by: Colin Ian King Signed-off-by: Dan Williams --- fs/ext4/super.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 3e58f952eddc..55772b2d05ee 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -3401,10 +3401,10 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent) unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO; ext4_group_t first_not_zeroed; - sbi->s_daxdev = dax_dev; if ((data && !orig_data) || !sbi) goto out_free_base; + sbi->s_daxdev = dax_dev; sbi->s_blockgroup_lock = kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL); if (!sbi->s_blockgroup_lock) -- cgit v1.2.3