ksmbd: fix slab-out-of-bounds in smb_strndup_from_utf16()

If ->NameOffset of smb2_create_req is smaller than Buffer offset of
smb2_create_req, slab-out-of-bounds read can happen from smb2_open.
This patch set the minimum value of the name offset to the buffer offset
to validate name length of smb2_create_req().

Cc: stable@vger.kernel.org
Reported-by: Xuanzhe Yu <yuxuanzhe@outlook.com>
Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
This commit is contained in:
Namjae Jeon 2024-03-16 23:36:36 +09:00 committed by Steve French
parent e758fa6956
commit a80a486d72

View File

@ -107,7 +107,10 @@ static int smb2_get_data_area_len(unsigned int *off, unsigned int *len,
case SMB2_CREATE:
{
unsigned short int name_off =
le16_to_cpu(((struct smb2_create_req *)hdr)->NameOffset);
max_t(unsigned short int,
le16_to_cpu(((struct smb2_create_req *)hdr)->NameOffset),
offsetof(struct smb2_create_req, Buffer));
unsigned short int name_len =
le16_to_cpu(((struct smb2_create_req *)hdr)->NameLength);