Hello,

On Mon, 15 Aug 2022 14:07:12 +0300 Alon Zahavi zahavi.alon@gmail.com wrote:

From: Alon Zahavi zahavi.alon@gmail.com

The bug occours due to a misuse of `attr` variable instead of `attr_b`. `attr` is being initialized as NULL, then being derenfernced as `attr->res.data_size`.

This bug causes a crash of the ntfs3 driver itself, If compiled directly to the kernel, it crashes the whole system.

Signed-off-by: Alon Zahavi zahavi.alon@gmail.com Co-developed-by: Tal Lossos tallossos@gmail.com Signed-off-by: Tal Lossos tallossos@gmail.com

This patch has now merged in mainline as 6d5c9e79b726cc473d40e9cb60976dbe8e669624. stable@, could you please merge this in stable kernels?

Fixes: be71b5cba2e64 ("fs/ntfs3: Add attrib operations") # 5.14

Thanks, SJ

---

fs/ntfs3/attrib.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/ntfs3/attrib.c b/fs/ntfs3/attrib.c index e8c00dda42ad..4e74bc8f01ed 100644 --- a/fs/ntfs3/attrib.c +++ b/fs/ntfs3/attrib.c @@ -1949,7 +1949,7 @@ int attr_punch_hole(struct ntfs_inode *ni, u64 vbo, u64 bytes, u32 *frame_size) return -ENOENT; if (!attr_b->non_res) {

• u32 data_size = le32_to_cpu(attr->res.data_size);
  

• u32 data_size = le32_to_cpu(attr_b->res.data_size);
  

  u32 from, to;

if (vbo > data_size) -- 2.25.1