Unverified Commit 019d22eb authored by Abdun Nihaal's avatar Abdun Nihaal Committed by Konstantin Komarov
Browse files

fs/ntfs3: Validate attribute data and valid sizes 

The data_size and valid_size fields of non resident attributes should be
less than the its alloc_size field, but this is not checked in
ntfs_read_mft function.

Syzbot reports a allocation order warning due to a large unchecked value
of data_size getting assigned to inode->i_size which is then passed to
kcalloc.

Add sanity check for ensuring that the data_size and valid_size fields
are not larger than alloc_size field.

Link: https://syzkaller.appspot.com/bug?extid=fa4648a5446460b7b963


Reported-and-tested-by: default avatar <syzbot+fa4648a5446460b7b963@syzkaller.appspotmail.com>
Fixes: (82cae269) fs/ntfs3: Add initialization of super block
Signed-off-by: default avatarAbdun Nihaal <abdun.nihaal@gmail.com>
Signed-off-by: default avatarKonstantin Komarov <almaz.alexandrovich@paragon-software.com>
parent 59bfd7a4

fs/ntfs3/inode.c

+7 −0
Original line number Diff line number Diff line
@@ -132,6 +132,13 @@ static struct inode *ntfs_read_mft(struct inode *inode, 
	if (le16_to_cpu(attr->name_off) + attr->name_len > asize)

		goto out;



	if (attr->non_res) {

		t64 = le64_to_cpu(attr->nres.alloc_size);

		if (le64_to_cpu(attr->nres.data_size) > t64 ||

		    le64_to_cpu(attr->nres.valid_size) > t64)

			goto out;

	}



	switch (attr->type) {

	case ATTR_STD:

		if (attr->non_res ||