Validate OutputBufferLength of QUERY_DIR, QUERY_INFO, IOCTL requests and
check the free size of response buffer for these requests.
Signed-off-by: Hyunchul Lee <hyc.lee@xxxxxxxxx>
---
fs/ksmbd/smb2pdu.c | 68 +++++++++++++++++++++++++++++++++++-----------
1 file changed, 52 insertions(+), 16 deletions(-)
diff --git a/fs/ksmbd/smb2pdu.c b/fs/ksmbd/smb2pdu.c
index 7999d8bc6892..e0f3a44e1599 100644
--- a/fs/ksmbd/smb2pdu.c
+++ b/fs/ksmbd/smb2pdu.c
@@ -3762,6 +3762,24 @@ static int verify_info_level(int info_level)
return 0;
}
+static int smb2_calc_max_out_buf_len(struct ksmbd_work *work,
+ unsigned short hdr2_len,
+ unsigned int out_buf_len)
+{
+ int free_len;
+
+ if (out_buf_len > work->conn->vals->max_trans_size)
+ return -EINVAL;
+
+ free_len = (int)(work->response_sz -
+ (get_rfc1002_len(work->response_buf) + 4)) -
+ hdr2_len;
+ if (free_len < 0)
+ return -EINVAL;
+
+ return min_t(int, out_buf_len, free_len);
+}
+
int smb2_query_dir(struct ksmbd_work *work)
{
struct ksmbd_conn *conn = work->conn;
@@ -3838,9 +3856,13 @@ int smb2_query_dir(struct ksmbd_work *work)
memset(&d_info, 0, sizeof(struct ksmbd_dir_info));
d_info.wptr = (char *)rsp->Buffer;
d_info.rptr = (char *)rsp->Buffer;
- d_info.out_buf_len = (work->response_sz - (get_rfc1002_len(rsp_org) + 4));
- d_info.out_buf_len = min_t(int, d_info.out_buf_len, le32_to_cpu(req->OutputBufferLength)) -
- sizeof(struct smb2_query_directory_rsp);
+ d_info.out_buf_len =
+ smb2_calc_max_out_buf_len(work, 8,
+ le32_to_cpu(req->OutputBufferLength));
+ if (d_info.out_buf_len < 0) {
+ rc = -EINVAL;
+ goto err_out;
+ }
d_info.flags = srch_flag;
/*
@@ -4074,12 +4096,11 @@ static int smb2_get_ea(struct ksmbd_work *work, struct ksmbd_file *fp,
le32_to_cpu(req->Flags));
}
- buf_free_len = work->response_sz -
- (get_rfc1002_len(rsp_org) + 4) -
- sizeof(struct smb2_query_info_rsp);
-
- if (le32_to_cpu(req->OutputBufferLength) < buf_free_len)
- buf_free_len = le32_to_cpu(req->OutputBufferLength);
+ buf_free_len =
+ smb2_calc_max_out_buf_len(work, 8,
+ le32_to_cpu(req->OutputBufferLength));
+ if (buf_free_len < 0)
+ return -EINVAL;
rc = ksmbd_vfs_listxattr(path->dentry, &xattr_list);
if (rc < 0) {
@@ -4390,6 +4411,8 @@ static void get_file_stream_info(struct ksmbd_work *work,
struct path *path = &fp->filp->f_path;
ssize_t xattr_list_len;
int nbytes = 0, streamlen, stream_name_len, next, idx = 0;
+ int buf_free_len;
+ struct smb2_query_info_req *req = ksmbd_req_buf_next(work);
generic_fillattr(file_mnt_user_ns(fp->filp), file_inode(fp->filp),
&stat);
@@ -4403,6 +4426,12 @@ static void get_file_stream_info(struct ksmbd_work *work,
goto out;
}
+ buf_free_len =
+ smb2_calc_max_out_buf_len(work, 8,
+ le32_to_cpu(req->OutputBufferLength));
+ if (buf_free_len < 0)
+ goto out;
+
while (idx < xattr_list_len) {
stream_name = xattr_list + idx;
streamlen = strlen(stream_name);
@@ -4427,6 +4456,10 @@ static void get_file_stream_info(struct ksmbd_work *work,
streamlen = snprintf(stream_buf, streamlen + 1,
":%s", &stream_name[XATTR_NAME_STREAM_LEN]);
+ next = sizeof(struct smb2_file_stream_info) + streamlen * 2;
+ if (next > buf_free_len)
+ break;
+
file_info = (struct smb2_file_stream_info *)&rsp->Buffer[nbytes];
streamlen = smbConvertToUTF16((__le16 *)file_info->StreamName,
stream_buf, streamlen,
@@ -4437,12 +4470,13 @@ static void get_file_stream_info(struct ksmbd_work *work,
file_info->StreamSize = cpu_to_le64(stream_name_len);
file_info->StreamAllocationSize = cpu_to_le64(stream_name_len);
- next = sizeof(struct smb2_file_stream_info) + streamlen;
nbytes += next;
+ buf_free_len -= next;
file_info->NextEntryOffset = cpu_to_le32(next);
}
- if (!S_ISDIR(stat.mode)) {
+ if (!S_ISDIR(stat.mode) &&
+ buf_free_len >= sizeof(struct smb2_file_stream_info) + 7 * 2) {
file_info = (struct smb2_file_stream_info *)
&rsp->Buffer[nbytes];
streamlen = smbConvertToUTF16((__le16 *)file_info->StreamName,
@@ -7453,11 +7487,13 @@ 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_t(u32, work->response_sz - work->next_smb2_rsp_hdr_off -
- (offsetof(struct smb2_ioctl_rsp, Buffer) - 4),
- out_buf_len);
+ ret = smb2_calc_max_out_buf_len(work, 48,
+ le32_to_cpu(req->MaxOutputResponse));
+ if (ret < 0) {
+ rsp->hdr.Status = STATUS_INVALID_PARAMETER;
+ goto out;
+ }
+ out_buf_len = (unsigned int)ret;
in_buf_len = le32_to_cpu(req->InputCount);
switch (cnt_code) {
--
2.25.1
