Ignore. Looking at the wrong code.
On Wed, Sep 22, 2021 at 1:48 PM ronnie sahlberg
<ronniesahlberg@xxxxxxxxx> wrote:
>
> I hope I look at the right patches/branches, appologies if not.
>
> Do you have a branch where you have all these patches applied?
>
> On Wed, Sep 22, 2021 at 12:28 PM Namjae Jeon <linkinjeon@xxxxxxxxxx> wrote:
> >
> > Add validation for request/response buffer size check in smb2_ioctl and
> > fsctl_copychunk() take copychunk_ioctl_req pointer and the other arguments
> > instead of smb2_ioctl_req structure and remove an unused smb2_ioctl_req
> > argument of fsctl_validate_negotiate_info.
> >
> > Cc: Ronnie Sahlberg <ronniesahlberg@xxxxxxxxx>
> > Cc: Ralph Böhme <slow@xxxxxxxxx>
> > Cc: Steve French <smfrench@xxxxxxxxx>
> > Signed-off-by: Namjae Jeon <linkinjeon@xxxxxxxxxx>
> > ---
> > v2:
> > - fix warning: variable 'ret' is used uninitialized ret.
> > v3:
> > - fsctl_copychunk() take copychunk_ioctl_req pointer and the other arguments
> > instead of smb2_ioctl_req structure.
> > - remove an unused smb2_ioctl_req argument of fsctl_validate_negotiate_info.
> > fs/ksmbd/smb2pdu.c | 87 ++++++++++++++++++++++++++++++++++++----------
> > 1 file changed, 68 insertions(+), 19 deletions(-)
> >
> > diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
> > index aaf50f677194..e96491c9ab92 100644
> > --- a/fs/ksmbd/smb2pdu.c
> > +++ b/fs/ksmbd/smb2pdu.c
> > @@ -6986,24 +6986,26 @@ int smb2_lock(struct ksmbd_work *work)
> > return err;
> > }
> >
> > -static int fsctl_copychunk(struct ksmbd_work *work, struct smb2_ioctl_req *req,
> > +static int fsctl_copychunk(struct ksmbd_work *work,
> > + struct copychunk_ioctl_req *ci_req,
> > + unsigned int cnt_code,
> > + unsigned int input_count,
> > + unsigned long long volatile_id,
> > + unsigned long long persistent_id,
> > struct smb2_ioctl_rsp *rsp)
> > {
> > - struct copychunk_ioctl_req *ci_req;
> > struct copychunk_ioctl_rsp *ci_rsp;
> > struct ksmbd_file *src_fp = NULL, *dst_fp = NULL;
> > struct srv_copychunk *chunks;
> > unsigned int i, chunk_count, chunk_count_written = 0;
> > unsigned int chunk_size_written = 0;
> > loff_t total_size_written = 0;
> > - int ret, cnt_code;
> > + int ret = 0;
> >
> > - cnt_code = le32_to_cpu(req->CntCode);
> > - ci_req = (struct copychunk_ioctl_req *)&req->Buffer[0];
> > ci_rsp = (struct copychunk_ioctl_rsp *)&rsp->Buffer[0];
> >
> > - rsp->VolatileFileId = req->VolatileFileId;
> > - rsp->PersistentFileId = req->PersistentFileId;
> > + rsp->VolatileFileId = cpu_to_le64(volatile_id);
> > + rsp->PersistentFileId = cpu_to_le64(persistent_id);
> > ci_rsp->ChunksWritten =
> > cpu_to_le32(ksmbd_server_side_copy_max_chunk_count());
> > ci_rsp->ChunkBytesWritten =
> > @@ -7013,12 +7015,13 @@ static int fsctl_copychunk(struct ksmbd_work *work, struct smb2_ioctl_req *req,
> >
> > chunks = (struct srv_copychunk *)&ci_req->Chunks[0];
> > chunk_count = le32_to_cpu(ci_req->ChunkCount);
> > + if (chunk_count == 0)
> > + goto out;
> > total_size_written = 0;
> >
> > /* verify the SRV_COPYCHUNK_COPY packet */
> > if (chunk_count > ksmbd_server_side_copy_max_chunk_count() ||
> > - le32_to_cpu(req->InputCount) <
> > - offsetof(struct copychunk_ioctl_req, Chunks) +
> > + input_count < offsetof(struct copychunk_ioctl_req, Chunks) +
> > chunk_count * sizeof(struct srv_copychunk)) {
> > rsp->hdr.Status = STATUS_INVALID_PARAMETER;
> > return -EINVAL;
> > @@ -7039,9 +7042,7 @@ static int fsctl_copychunk(struct ksmbd_work *work, struct smb2_ioctl_req *req,
> >
> > src_fp = ksmbd_lookup_foreign_fd(work,
> > le64_to_cpu(ci_req->ResumeKey[0]));
> > - dst_fp = ksmbd_lookup_fd_slow(work,
> > - le64_to_cpu(req->VolatileFileId),
> > - le64_to_cpu(req->PersistentFileId));
> > + dst_fp = ksmbd_lookup_fd_slow(work, volatile_id, persistent_id);
> > ret = -EINVAL;
> > if (!src_fp ||
> > src_fp->persistent_id != le64_to_cpu(ci_req->ResumeKey[1])) {
> > @@ -7116,8 +7117,8 @@ static __be32 idev_ipv4_address(struct in_device *idev)
> > }
> >
> > static int fsctl_query_iface_info_ioctl(struct ksmbd_conn *conn,
> > - struct smb2_ioctl_req *req,
> > - struct smb2_ioctl_rsp *rsp)
> > + struct smb2_ioctl_rsp *rsp,
> > + int out_buf_len)
> > {
> > struct network_interface_info_ioctl_rsp *nii_rsp = NULL;
> > int nbytes = 0;
> > @@ -7200,6 +7201,8 @@ static int fsctl_query_iface_info_ioctl(struct ksmbd_conn *conn,
> > sockaddr_storage->addr6.ScopeId = 0;
> > }
> >
> > + if (out_buf_len < sizeof(struct network_interface_info_ioctl_rsp))
> > + break;
> > nbytes += sizeof(struct network_interface_info_ioctl_rsp);
> > }
> > rtnl_unlock();
> > @@ -7220,11 +7223,16 @@ static int fsctl_query_iface_info_ioctl(struct ksmbd_conn *conn,
> >
> > static int fsctl_validate_negotiate_info(struct ksmbd_conn *conn,
> > struct validate_negotiate_info_req *neg_req,
> > - struct validate_negotiate_info_rsp *neg_rsp)
> > + struct validate_negotiate_info_rsp *neg_rsp,
> > + int in_buf_len)
> > {
> > int ret = 0;
> > int dialect;
> >
> > + if (in_buf_len < sizeof(struct validate_negotiate_info_req) +
> > + le16_to_cpu(neg_req->DialectCount) * sizeof(__le16))
> > + return -EINVAL;
> > +
> > dialect = ksmbd_lookup_dialect_by_id(neg_req->Dialects,
> > neg_req->DialectCount);
> > if (dialect == BAD_PROT_ID || dialect != conn->dialect) {
> > @@ -7400,7 +7408,7 @@ int smb2_ioctl(struct ksmbd_work *work)
> > struct smb2_ioctl_req *req;
> > struct smb2_ioctl_rsp *rsp, *rsp_org;
> > int cnt_code, nbytes = 0;
> > - int out_buf_len;
> > + int out_buf_len, in_buf_len;
> > u64 id = KSMBD_NO_FID;
> > struct ksmbd_conn *conn = work->conn;
> > int ret = 0;
> > @@ -7430,6 +7438,7 @@ int smb2_ioctl(struct ksmbd_work *work)
> > cnt_code = le32_to_cpu(req->CntCode);
> > out_buf_len = le32_to_cpu(req->MaxOutputResponse);
> > out_buf_len = min(KSMBD_IPC_MAX_PAYLOAD, out_buf_len);
> > + in_buf_len = le32_to_cpu(req->InputCount);
>
> Do you check if you have these many bytes remaining in the buffer?
>
> Also earlier in this function, where you assign req.
> If this is not a component in a compound, then you assign req =
> work->request_buf
> which starts with 4 bytes for the length and the smb2_hdr starts at
> offset 4, right?
>
> But if the ioctl is inside a compound, you assign req = ksmbd_req_buf_next()
> which just returns the offset to wherever NextCommand is?
> There are two problems here.
> Now req points to something where teh smb2 header starts at offset 0
> instead of 4.
> I unfortunately do not have any code to create Create/Ioctl/Close
> compounds to test this,
> but it looks like this is a problem.
>
> The second is that there is no check I can see that we validate that
> req now points to valid data,
> which means that when we dereference req just a few lines later
> (req->VolatileFileId)
> we might read random data beyond the end of request_buf or we might oops.
>
>
> The same might be an issue in other functions as well.
>
>
> >
> > switch (cnt_code) {
> > case FSCTL_DFS_GET_REFERRALS:
> > @@ -7465,9 +7474,16 @@ int smb2_ioctl(struct ksmbd_work *work)
> > goto out;
> > }
> >
> > + if (in_buf_len < sizeof(struct validate_negotiate_info_req))
> > + return -EINVAL;
> > +
> > + if (out_buf_len < sizeof(struct validate_negotiate_info_rsp))
> > + return -EINVAL;
> > +
> > ret = fsctl_validate_negotiate_info(conn,
> > (struct validate_negotiate_info_req *)&req->Buffer[0],
> > - (struct validate_negotiate_info_rsp *)&rsp->Buffer[0]);
> > + (struct validate_negotiate_info_rsp *)&rsp->Buffer[0],
> > + in_buf_len);
> > if (ret < 0)
> > goto out;
> >
> > @@ -7476,7 +7492,7 @@ int smb2_ioctl(struct ksmbd_work *work)
> > rsp->VolatileFileId = cpu_to_le64(SMB2_NO_FID);
> > break;
> > case FSCTL_QUERY_NETWORK_INTERFACE_INFO:
> > - nbytes = fsctl_query_iface_info_ioctl(conn, req, rsp);
> > + nbytes = fsctl_query_iface_info_ioctl(conn, rsp, out_buf_len);
> > if (nbytes < 0)
> > goto out;
> > break;
> > @@ -7503,15 +7519,33 @@ int smb2_ioctl(struct ksmbd_work *work)
> > goto out;
> > }
> >
> > + if (in_buf_len < sizeof(struct copychunk_ioctl_req)) {
> > + ret = -EINVAL;
> > + goto out;
> > + }
> > +
> > if (out_buf_len < sizeof(struct copychunk_ioctl_rsp)) {
> > ret = -EINVAL;
> > goto out;
> > }
> >
> > nbytes = sizeof(struct copychunk_ioctl_rsp);
> > - fsctl_copychunk(work, req, rsp);
> > + rsp->VolatileFileId = req->VolatileFileId;
> > + rsp->PersistentFileId = req->PersistentFileId;
> > + fsctl_copychunk(work,
> > + (struct copychunk_ioctl_req *)&req->Buffer[0],
> > + le32_to_cpu(req->CntCode),
> > + le32_to_cpu(req->InputCount),
> > + le64_to_cpu(req->VolatileFileId),
> > + le64_to_cpu(req->PersistentFileId),
> > + rsp);
> > break;
> > case FSCTL_SET_SPARSE:
> > + if (in_buf_len < sizeof(struct file_sparse)) {
> > + ret = -EINVAL;
> > + goto out;
> > + }
> > +
> > ret = fsctl_set_sparse(work, id,
> > (struct file_sparse *)&req->Buffer[0]);
> > if (ret < 0)
> > @@ -7530,6 +7564,11 @@ int smb2_ioctl(struct ksmbd_work *work)
> > goto out;
> > }
> >
> > + if (in_buf_len < sizeof(struct file_zero_data_information)) {
> > + ret = -EINVAL;
> > + goto out;
> > + }
> > +
> > zero_data =
> > (struct file_zero_data_information *)&req->Buffer[0];
> >
> > @@ -7549,6 +7588,11 @@ int smb2_ioctl(struct ksmbd_work *work)
> > break;
> > }
> > case FSCTL_QUERY_ALLOCATED_RANGES:
> > + if (in_buf_len < sizeof(struct file_allocated_range_buffer)) {
> > + ret = -EINVAL;
> > + goto out;
> > + }
> > +
> > ret = fsctl_query_allocated_ranges(work, id,
> > (struct file_allocated_range_buffer *)&req->Buffer[0],
> > (struct file_allocated_range_buffer *)&rsp->Buffer[0],
> > @@ -7589,6 +7633,11 @@ int smb2_ioctl(struct ksmbd_work *work)
> > struct duplicate_extents_to_file *dup_ext;
> > loff_t src_off, dst_off, length, cloned;
> >
> > + if (in_buf_len < sizeof(struct duplicate_extents_to_file)) {
> > + ret = -EINVAL;
> > + goto out;
> > + }
> > +
> > dup_ext = (struct duplicate_extents_to_file *)&req->Buffer[0];
> >
> > fp_in = ksmbd_lookup_fd_slow(work, dup_ext->VolatileFileHandle,
> > --
> > 2.25.1
> >
