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