From 0a475402ec1126c8aaa4aa3e991c149ce8d29ed8 Mon Sep 17 00:00:00 2001
From: zzzzzzzzzy9 <zhang.yu58@zte.com.cn>
Date: Tue, 1 Jul 2025 19:10:46 +0800
Subject: [PATCH] fs/ntfs3: Check 'folio' pointer for NULL

commit 6c8054d590668629bb2eb6fb4cbf22455d08ada8 upstream.

It can be NULL if bmap is called.

Fixes: 82cae269cfa95 ("fs/ntfs3: Add initialization of super block")
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Fixes: CVE-2024-38625
Signed-off-by: zzzzzzzzzy9 <zhang.yu58@zte.com.cn>
Reviewed-by: Zhang Run<zhang.run@zte.com.cn>
Link: https://gitee.com/anolis/embedded-kernel/pulls/983
---
 fs/ntfs3/inode.c | 17 +++++++++++------
 1 file changed, 11 insertions(+), 6 deletions(-)

diff --git a/fs/ntfs3/inode.c b/fs/ntfs3/inode.c
index 34f2e16f3f5b..e9314778a9d0 100644
--- a/fs/ntfs3/inode.c
+++ b/fs/ntfs3/inode.c
@@ -570,13 +570,18 @@ static noinline int ntfs_get_block_vbo(struct inode *inode, u64 vbo,
 	clear_buffer_uptodate(bh);
 
 	if (is_resident(ni)) {
-		ni_lock(ni);
-		err = attr_data_read_resident(ni, &folio->page);
-		ni_unlock(ni);
-
-		if (!err)
-			set_buffer_uptodate(bh);
+		bh->b_blocknr = RESIDENT_LCN;
 		bh->b_size = block_size;
+		if (!folio) {
+			err = 0;
+		} else {
+			ni_lock(ni);
+			err = attr_data_read_resident(ni, &folio->page);
+			ni_unlock(ni);
+
+			if (!err)
+				set_buffer_uptodate(bh);
+		}
 		return err;
 	}
 
-- 
Gitee