From 019d22eb0eb707fc099e6e8fad9b3933236a06d0 Mon Sep 17 00:00:00 2001 From: Abdun Nihaal Date: Tue, 4 Oct 2022 08:45:02 +0530 Subject: 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: syzbot+fa4648a5446460b7b963@syzkaller.appspotmail.com Fixes: (82cae269cfa95) fs/ntfs3: Add initialization of super block Signed-off-by: Abdun Nihaal Signed-off-by: Konstantin Komarov --- fs/ntfs3/inode.c | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'fs/ntfs3') diff --git a/fs/ntfs3/inode.c b/fs/ntfs3/inode.c index e9cf00d14733..9c244029be75 100644 --- a/fs/ntfs3/inode.c +++ b/fs/ntfs3/inode.c @@ -132,6 +132,13 @@ next_attr: 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 || -- cgit