cifs: update smb2_queryfs() to use compounding

Change smb2_queryfs() to use a Create/QueryInfo/Close compound request.

Signed-off-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Reviewed-by: Paulo Alcantara <palcantara@suse.com>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>

4 files changed, 131 insertions, 26 deletions

diff --git a/fs/cifs/smb2ops.c b/fs/cifs/smb2ops.c
index d23715062c8e..15c7cbde2f39 100644
--- a/fs/cifs/smb2ops.c
+++ b/fs/cifs/smb2ops.c
@@ -1524,15 +1524,66 @@ smb2_oplock_response(struct cifs_tcon *tcon, struct cifs_fid *fid,
 				 CIFS_CACHE_READ(cinode) ? 1 : 0);
 }
 
+static void
+smb2_set_related(struct smb_rqst *rqst)
+{
+	struct smb2_sync_hdr *shdr;
+
+	shdr = (struct smb2_sync_hdr *)(rqst->rq_iov[0].iov_base);
+	shdr->Flags |= SMB2_FLAGS_RELATED_OPERATIONS;
+}
+
+char smb2_padding[7] = {0, 0, 0, 0, 0, 0, 0};
+
+static void
+smb2_set_next_command(struct TCP_Server_Info *server, struct smb_rqst *rqst)
+{
+	struct smb2_sync_hdr *shdr;
+	unsigned long len = smb_rqst_len(server, rqst);
+
+	/* SMB headers in a compound are 8 byte aligned. */
+	if (len & 7) {
+		rqst->rq_iov[rqst->rq_nvec].iov_base = smb2_padding;
+		rqst->rq_iov[rqst->rq_nvec].iov_len = 8 - (len & 7);
+		rqst->rq_nvec++;
+		len = smb_rqst_len(server, rqst);
+	}
+
+	shdr = (struct smb2_sync_hdr *)(rqst->rq_iov[0].iov_base);
+	shdr->NextCommand = cpu_to_le32(len);
+}
+
 static int
 smb2_queryfs(const unsigned int xid, struct cifs_tcon *tcon,
 	     struct kstatfs *buf)
 {
-	int rc;
+	struct smb2_query_info_rsp *rsp;
+	struct smb2_fs_full_size_info *info = NULL;
+	struct smb_rqst rqst[3];
+	int resp_buftype[3];
+	struct kvec rsp_iov[3];
+	struct kvec open_iov[5]; /* 4 + potential padding. */
+	struct kvec qi_iov[1];
+	struct kvec close_iov[1];
+	struct cifs_ses *ses = tcon->ses;
+	struct TCP_Server_Info *server = ses->server;
 	__le16 srch_path = 0; /* Null - open root of share */
 	u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
 	struct cifs_open_parms oparms;
 	struct cifs_fid fid;
+	int flags = 0;
+	int rc;
+
+	if (smb3_encryption_required(tcon))
+		flags |= CIFS_TRANSFORM_REQ;
+
+	memset(rqst, 0, sizeof(rqst));
+	memset(resp_buftype, 0, sizeof(resp_buftype));
+	memset(rsp_iov, 0, sizeof(rsp_iov));
+
+	memset(&open_iov, 0, sizeof(open_iov));
+	rqst[0].rq_iov = open_iov;
+	rqst[0].rq_nvec = 4;
 
 	oparms.tcon = tcon;
 	oparms.desired_access = FILE_READ_ATTRIBUTES;
@@ -1541,13 +1592,56 @@ smb2_queryfs(const unsigned int xid, struct cifs_tcon *tcon,
 	oparms.fid = &fid;
 	oparms.reconnect = false;
 
-	rc = SMB2_open(xid, &oparms, &srch_path, &oplock, NULL, NULL, NULL);
+	rc = SMB2_open_init(tcon, &rqst[0], &oplock, &oparms, &srch_path);
 	if (rc)
-		return rc;
+		goto qfs_exit;
+	smb2_set_next_command(server, &rqst[0]);
+
+	memset(&qi_iov, 0, sizeof(qi_iov));
+	rqst[1].rq_iov = qi_iov;
+	rqst[1].rq_nvec = 1;
+
+	rc = SMB2_query_info_init(tcon, &rqst[1], COMPOUND_FID, COMPOUND_FID,
+				  FS_FULL_SIZE_INFORMATION,
+				  SMB2_O_INFO_FILESYSTEM, 0,
+				  sizeof(struct smb2_fs_full_size_info));
+	if (rc)
+		goto qfs_exit;
+	smb2_set_next_command(server, &rqst[1]);
+	smb2_set_related(&rqst[1]);
+
+	memset(&close_iov, 0, sizeof(close_iov));
+	rqst[2].rq_iov = close_iov;
+	rqst[2].rq_nvec = 1;
+
+	rc = SMB2_close_init(tcon, &rqst[2], COMPOUND_FID, COMPOUND_FID);
+	if (rc)
+		goto qfs_exit;
+	smb2_set_related(&rqst[2]);
+
+	rc = compound_send_recv(xid, ses, flags, 3, rqst,
+				resp_buftype, rsp_iov);
+	if (rc)
+		goto qfs_exit;
+
+	rsp = (struct smb2_query_info_rsp *)rsp_iov[1].iov_base;
 	buf->f_type = SMB2_MAGIC_NUMBER;
-	rc = SMB2_QFS_info(xid, tcon, fid.persistent_fid, fid.volatile_fid,
-			   buf);
-	SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
+	info = (struct smb2_fs_full_size_info *)(
+		le16_to_cpu(rsp->OutputBufferOffset) + (char *)rsp);
+	rc = smb2_validate_iov(le16_to_cpu(rsp->OutputBufferOffset),
+			       le32_to_cpu(rsp->OutputBufferLength),
+			       &rsp_iov[1],
+			       sizeof(struct smb2_fs_full_size_info));
+	if (!rc)
+		smb2_copy_fs_info_to_kstatfs(info, buf);
+
+qfs_exit:
+	SMB2_open_free(&rqst[0]);
+	SMB2_query_info_free(&rqst[1]);
+	SMB2_close_free(&rqst[2]);
+	free_rsp_buf(resp_buftype[0], rsp_iov[0].iov_base);
+	free_rsp_buf(resp_buftype[1], rsp_iov[1].iov_base);
+	free_rsp_buf(resp_buftype[2], rsp_iov[2].iov_base);
 	return rc;
 }
 
diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index a5009a1c9bce..faf2b779e5cb 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -80,7 +80,7 @@ static const int smb2_req_struct_sizes[NUMBER_OF_SMB2_COMMANDS] = {
 	/* SMB2_OPLOCK_BREAK */ 24 /* BB this is 36 for LEASE_BREAK variant */
 };
 
-static int smb3_encryption_required(const struct cifs_tcon *tcon)
+int smb3_encryption_required(const struct cifs_tcon *tcon)
 {
 	if (!tcon)
 		return 0;
@@ -2182,7 +2182,8 @@ SMB2_open_free(struct smb_rqst *rqst)
 
 	cifs_small_buf_release(rqst->rq_iov[0].iov_base);
 	for (i = 1; i < rqst->rq_nvec; i++)
-		kfree(rqst->rq_iov[i].iov_base);
+		if (rqst->rq_iov[i].iov_base != smb2_padding)
+			kfree(rqst->rq_iov[i].iov_base);
 }
 
 int
@@ -2528,9 +2529,9 @@ SMB2_close(const unsigned int xid, struct cifs_tcon *tcon,
 	return SMB2_close_flags(xid, tcon, persistent_fid, volatile_fid, 0);
 }
 
-static int
-validate_iov(unsigned int offset, unsigned int buffer_length,
-	     struct kvec *iov, unsigned int min_buf_size)
+int
+smb2_validate_iov(unsigned int offset, unsigned int buffer_length,
+		  struct kvec *iov, unsigned int min_buf_size)
 {
 	unsigned int smb_len = iov->iov_len;
 	char *end_of_smb = smb_len + (char *)iov->iov_base;
@@ -2574,7 +2575,7 @@ validate_and_copy_iov(unsigned int offset, unsigned int buffer_length,
 	if (!data)
 		return -EINVAL;
 
-	rc = validate_iov(offset, buffer_length, iov, minbufsize);
+	rc = smb2_validate_iov(offset, buffer_length, iov, minbufsize);
 	if (rc)
 		return rc;
 
@@ -3646,9 +3647,9 @@ SMB2_query_directory(const unsigned int xid, struct cifs_tcon *tcon,
 		goto qdir_exit;
 	}
 
-	rc = validate_iov(le16_to_cpu(rsp->OutputBufferOffset),
-			  le32_to_cpu(rsp->OutputBufferLength), &rsp_iov,
-			  info_buf_size);
+	rc = smb2_validate_iov(le16_to_cpu(rsp->OutputBufferOffset),
+			       le32_to_cpu(rsp->OutputBufferLength), &rsp_iov,
+			       info_buf_size);
 	if (rc)
 		goto qdir_exit;
 
@@ -3950,9 +3951,9 @@ SMB2_oplock_break(const unsigned int xid, struct cifs_tcon *tcon,
 	return rc;
 }
 
-static void
-copy_fs_info_to_kstatfs(struct smb2_fs_full_size_info *pfs_inf,
-			struct kstatfs *kst)
+void
+smb2_copy_fs_info_to_kstatfs(struct smb2_fs_full_size_info *pfs_inf,
+			     struct kstatfs *kst)
 {
 	kst->f_bsize = le32_to_cpu(pfs_inf->BytesPerSector) *
 			  le32_to_cpu(pfs_inf->SectorsPerAllocationUnit);
@@ -4054,9 +4055,9 @@ SMB311_posix_qfs_info(const unsigned int xid, struct cifs_tcon *tcon,
 
 	info = (FILE_SYSTEM_POSIX_INFO *)(
 		le16_to_cpu(rsp->OutputBufferOffset) + (char *)rsp);
-	rc = validate_iov(le16_to_cpu(rsp->OutputBufferOffset),
-			  le32_to_cpu(rsp->OutputBufferLength), &rsp_iov,
-			  sizeof(FILE_SYSTEM_POSIX_INFO));
+	rc = smb2_validate_iov(le16_to_cpu(rsp->OutputBufferOffset),
+			       le32_to_cpu(rsp->OutputBufferLength), &rsp_iov,
+			       sizeof(FILE_SYSTEM_POSIX_INFO));
 	if (!rc)
 		copy_posix_fs_info_to_kstatfs(info, fsdata);
 
@@ -4102,11 +4103,11 @@ SMB2_QFS_info(const unsigned int xid, struct cifs_tcon *tcon,
 
 	info = (struct smb2_fs_full_size_info *)(
 		le16_to_cpu(rsp->OutputBufferOffset) + (char *)rsp);
-	rc = validate_iov(le16_to_cpu(rsp->OutputBufferOffset),
-			  le32_to_cpu(rsp->OutputBufferLength), &rsp_iov,
-			  sizeof(struct smb2_fs_full_size_info));
+	rc = smb2_validate_iov(le16_to_cpu(rsp->OutputBufferOffset),
+			       le32_to_cpu(rsp->OutputBufferLength), &rsp_iov,
+			       sizeof(struct smb2_fs_full_size_info));
 	if (!rc)
-		copy_fs_info_to_kstatfs(info, fsdata);
+		smb2_copy_fs_info_to_kstatfs(info, fsdata);
 
 qfsinf_exit:
 	free_rsp_buf(resp_buftype, rsp_iov.iov_base);
@@ -4166,7 +4167,7 @@ SMB2_QFS_attr(const unsigned int xid, struct cifs_tcon *tcon,
 
 	rsp_len = le32_to_cpu(rsp->OutputBufferLength);
 	offset = le16_to_cpu(rsp->OutputBufferOffset);
-	rc = validate_iov(offset, rsp_len, &rsp_iov, min_len);
+	rc = smb2_validate_iov(offset, rsp_len, &rsp_iov, min_len);
 	if (rc)
 		goto qfsattr_exit;
 
diff --git a/fs/cifs/smb2pdu.h b/fs/cifs/smb2pdu.h
index ecb0feeac844..cf37c2f3f3b8 100644
--- a/fs/cifs/smb2pdu.h
+++ b/fs/cifs/smb2pdu.h
@@ -153,6 +153,8 @@ struct smb2_transform_hdr {
  *
  */
 
+#define COMPOUND_FID 0xFFFFFFFFFFFFFFFFULL
+
 #define SMB2_ERROR_STRUCTURE_SIZE2 cpu_to_le16(9)
 
 struct smb2_err_rsp {
@@ -1373,4 +1375,6 @@ struct smb2_file_eof_info { /* encoding of request for level 10 */
 	__le64 EndOfFile; /* new end of file value */
 } __packed; /* level 20 Set */
 
+extern char smb2_padding[7];
+
 #endif				/* _SMB2PDU_H */
diff --git a/fs/cifs/smb2proto.h b/fs/cifs/smb2proto.h
index 57bdd2711974..b4076577eeb7 100644
--- a/fs/cifs/smb2proto.h
+++ b/fs/cifs/smb2proto.h
@@ -229,6 +229,12 @@ extern int smb3_validate_negotiate(const unsigned int, struct cifs_tcon *);
 
 extern enum securityEnum smb2_select_sectype(struct TCP_Server_Info *,
 					enum securityEnum);
+extern int smb3_encryption_required(const struct cifs_tcon *tcon);
+extern int smb2_validate_iov(unsigned int offset, unsigned int buffer_length,
+			     struct kvec *iov, unsigned int min_buf_size);
+extern void smb2_copy_fs_info_to_kstatfs(
+	 struct smb2_fs_full_size_info *pfs_inf,
+	 struct kstatfs *kst);
 extern int smb311_crypto_shash_allocate(struct TCP_Server_Info *server);
 extern int smb311_update_preauth_hash(struct cifs_ses *ses,
 				      struct kvec *iov, int nvec);