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From 8c83a4851da1c7eda83098ade238665b15774da3 Mon Sep 17 00:00:00 2001
From: Dan Carpenter <dan.carpenter@oracle.com>
Date: Tue, 24 Aug 2021 10:50:15 +0300
Subject: [Backport 8c83a4851da1] src: Potential NULL dereference in
 hdr_find_split()

The "e" pointer is dereferenced before it has been checked for NULL.
Move the dereference after the NULL check to prevent an Oops.

Fixes: 82cae269cfa9 ("src: Add initialization of super block")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Kari Argillander <kari.argillander@gmail.com>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
---
 src/index.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/index.c b/src/index.c
index 5fb41c9c89100aee4d6d0e8f7cf65556aec11250..f4729aa50671f27de961305744b3839588696108 100644
--- a/src/index.c
+++ b/src/index.c
@@ -557,11 +557,12 @@ static const struct NTFS_DE *hdr_find_split(const struct INDEX_HDR *hdr)
 	size_t o;
 	const struct NTFS_DE *e = hdr_first_de(hdr);
 	u32 used_2 = le32_to_cpu(hdr->used) >> 1;
-	u16 esize = le16_to_cpu(e->size);
+	u16 esize;
 
 	if (!e || de_is_last(e))
 		return NULL;
 
+	esize = le16_to_cpu(e->size);
 	for (o = le32_to_cpu(hdr->de_off) + esize; o < used_2; o += esize) {
 		const struct NTFS_DE *p = e;
 
-- 
2.31.1