[PATCH 6.1 019/473] fs/ntfs3: Fix case when index is reused during tree transformation

Greg Kroah-Hartman
2024-06-06T14:12:27Z

From: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>

commit 05afeeebcac850a016ec4fb1f681ceda11963562 upstream.

In most cases when adding a cluster to the directory index,
they are placed at the end, and in the bitmap, this cluster corresponds
to the last bit. The new directory size is calculated as follows:

data_size = (u64)(bit + 1) << indx->index_bits;

In the case of reusing a non-final cluster from the index,
data_size is calculated incorrectly, resulting in the directory size
differing from the actual size.

A check for cluster reuse has been added, and the size update is skipped.

Fixes: 82cae269cfa95 ("fs/ntfs3: Add initialization of super block")
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
fs/ntfs3/index.c | 6 ++++++
1 file changed, 6 insertions(+)

--- a/fs/ntfs3/index.c
+++ b/fs/ntfs3/index.c
@@ -1531,6 +1531,11 @@ static int indx_add_allocate(struct ntfs
goto out1;
}

+ if (data_size <= le64_to_cpu(alloc->nres.data_size)) {
+ /* Reuse index. */
+ goto out;
+ }
+
/* Increase allocation. */
err = attr_set_size(ni, ATTR_ALLOC, in->name, in->name_len,
&indx->alloc_run, data_size, &data_size, true,
@@ -1541,6 +1546,7 @@ static int indx_add_allocate(struct ntfs
goto out1;
}

+out:
*vbn = bit << indx->idx2vbn_bits;

return 0;