Merge branch 'for-linus' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs fixes from Steve French:
 "Fixes for 4 cifs bugs, including a reconnect problem, a problem
  parsing responses to SMB2 open request, and setting nlink incorrectly
  to some servers which don't report it properly on the wire.  Also
  improves data integrity on reconnect with series from Pavel which adds
  durable handle support for SMB2."

* 'for-linus' of git://git.samba.org/sfrench/cifs-2.6:
  CIFS: Fix a deadlock when a file is reopened
  CIFS: Reopen the file if reconnect durable handle failed
  [CIFS] Fix minor endian error in durable handle patch series
  CIFS: Reconnect durable handles for SMB2
  CIFS: Make SMB2_open use cifs_open_parms struct
  CIFS: Introduce cifs_open_parms struct
  CIFS: Request durable open for SMB2 opens
  CIFS: Simplify SMB2 create context handling
  CIFS: Simplify SMB2_open code path
  CIFS: Respect create_options in smb2_open_file
  CIFS: Fix lease context buffer parsing
  [CIFS] use sensible file nlink values if unprovided
  Limit allocation of crypto mechanisms to dialect which requires

1 files changed, 159 insertions, 61 deletions

diff --git a/fs/cifs/smb2pdu.c b/fs/cifs/smb2pdu.c
index 2b312e4eeaa6..abc9c2809b51 100644
--- a/fs/cifs/smb2pdu.c
+++ b/fs/cifs/smb2pdu.c
@@ -847,29 +847,76 @@ create_lease_buf(u8 *lease_key, u8 oplock)
 	return buf;
 }
 
+static struct create_durable *
+create_durable_buf(void)
+{
+	struct create_durable *buf;
+
+	buf = kzalloc(sizeof(struct create_durable), GFP_KERNEL);
+	if (!buf)
+		return NULL;
+
+	buf->ccontext.DataOffset = cpu_to_le16(offsetof
+					(struct create_durable, Data));
+	buf->ccontext.DataLength = cpu_to_le32(16);
+	buf->ccontext.NameOffset = cpu_to_le16(offsetof
+				(struct create_durable, Name));
+	buf->ccontext.NameLength = cpu_to_le16(4);
+	buf->Name[0] = 'D';
+	buf->Name[1] = 'H';
+	buf->Name[2] = 'n';
+	buf->Name[3] = 'Q';
+	return buf;
+}
+
+static struct create_durable *
+create_reconnect_durable_buf(struct cifs_fid *fid)
+{
+	struct create_durable *buf;
+
+	buf = kzalloc(sizeof(struct create_durable), GFP_KERNEL);
+	if (!buf)
+		return NULL;
+
+	buf->ccontext.DataOffset = cpu_to_le16(offsetof
+					(struct create_durable, Data));
+	buf->ccontext.DataLength = cpu_to_le32(16);
+	buf->ccontext.NameOffset = cpu_to_le16(offsetof
+				(struct create_durable, Name));
+	buf->ccontext.NameLength = cpu_to_le16(4);
+	buf->Data.Fid.PersistentFileId = fid->persistent_fid;
+	buf->Data.Fid.VolatileFileId = fid->volatile_fid;
+	buf->Name[0] = 'D';
+	buf->Name[1] = 'H';
+	buf->Name[2] = 'n';
+	buf->Name[3] = 'C';
+	return buf;
+}
+
 static __u8
 parse_lease_state(struct smb2_create_rsp *rsp)
 {
 	char *data_offset;
 	struct create_lease *lc;
 	bool found = false;
+	unsigned int next = 0;
+	char *name;
 
-	data_offset = (char *)rsp;
-	data_offset += 4 + le32_to_cpu(rsp->CreateContextsOffset);
+	data_offset = (char *)rsp + 4 + le32_to_cpu(rsp->CreateContextsOffset);
 	lc = (struct create_lease *)data_offset;
 	do {
-		char *name = le16_to_cpu(lc->ccontext.NameOffset) + (char *)lc;
+		lc = (struct create_lease *)((char *)lc + next);
+		name = le16_to_cpu(lc->ccontext.NameOffset) + (char *)lc;
 		if (le16_to_cpu(lc->ccontext.NameLength) != 4 ||
 		    strncmp(name, "RqLs", 4)) {
-			lc = (struct create_lease *)((char *)lc
-					+ le32_to_cpu(lc->ccontext.Next));
+			next = le32_to_cpu(lc->ccontext.Next);
 			continue;
 		}
 		if (lc->lcontext.LeaseFlags & SMB2_LEASE_FLAG_BREAK_IN_PROGRESS)
 			return SMB2_OPLOCK_LEVEL_NOCHANGE;
 		found = true;
 		break;
-	} while (le32_to_cpu(lc->ccontext.Next) != 0);
+	} while (next != 0);
 
 	if (!found)
 		return 0;
@@ -877,23 +924,74 @@ parse_lease_state(struct smb2_create_rsp *rsp)
 	return smb2_map_lease_to_oplock(lc->lcontext.LeaseState);
 }
 
+static int
+add_lease_context(struct kvec *iov, unsigned int *num_iovec, __u8 *oplock)
+{
+	struct smb2_create_req *req = iov[0].iov_base;
+	unsigned int num = *num_iovec;
+
+	iov[num].iov_base = create_lease_buf(oplock+1, *oplock);
+	if (iov[num].iov_base == NULL)
+		return -ENOMEM;
+	iov[num].iov_len = sizeof(struct create_lease);
+	req->RequestedOplockLevel = SMB2_OPLOCK_LEVEL_LEASE;
+	if (!req->CreateContextsOffset)
+		req->CreateContextsOffset = cpu_to_le32(
+				sizeof(struct smb2_create_req) - 4 +
+				iov[num - 1].iov_len);
+	req->CreateContextsLength = cpu_to_le32(
+				le32_to_cpu(req->CreateContextsLength) +
+				sizeof(struct create_lease));
+	inc_rfc1001_len(&req->hdr, sizeof(struct create_lease));
+	*num_iovec = num + 1;
+	return 0;
+}
+
+static int
+add_durable_context(struct kvec *iov, unsigned int *num_iovec,
+		    struct cifs_open_parms *oparms)
+{
+	struct smb2_create_req *req = iov[0].iov_base;
+	unsigned int num = *num_iovec;
+
+	if (oparms->reconnect) {
+		iov[num].iov_base = create_reconnect_durable_buf(oparms->fid);
+		/* indicate that we don't need to relock the file */
+		oparms->reconnect = false;
+	} else
+		iov[num].iov_base = create_durable_buf();
+	if (iov[num].iov_base == NULL)
+		return -ENOMEM;
+	iov[num].iov_len = sizeof(struct create_durable);
+	if (!req->CreateContextsOffset)
+		req->CreateContextsOffset =
+			cpu_to_le32(sizeof(struct smb2_create_req) - 4 +
+								iov[1].iov_len);
+	req->CreateContextsLength =
+			cpu_to_le32(le32_to_cpu(req->CreateContextsLength) +
+						sizeof(struct create_durable));
+	inc_rfc1001_len(&req->hdr, sizeof(struct create_durable));
+	*num_iovec = num + 1;
+	return 0;
+}
+
 int
-SMB2_open(const unsigned int xid, struct cifs_tcon *tcon, __le16 *path,
-	  u64 *persistent_fid, u64 *volatile_fid, __u32 desired_access,
-	  __u32 create_disposition, __u32 file_attributes, __u32 create_options,
+SMB2_open(const unsigned int xid, struct cifs_open_parms *oparms, __le16 *path,
 	  __u8 *oplock, struct smb2_file_all_info *buf)
 {
 	struct smb2_create_req *req;
 	struct smb2_create_rsp *rsp;
 	struct TCP_Server_Info *server;
+	struct cifs_tcon *tcon = oparms->tcon;
 	struct cifs_ses *ses = tcon->ses;
-	struct kvec iov[3];
+	struct kvec iov[4];
 	int resp_buftype;
 	int uni_path_len;
 	__le16 *copy_path = NULL;
 	int copy_size;
 	int rc = 0;
-	int num_iovecs = 2;
+	unsigned int num_iovecs = 2;
+	__u32 file_attributes = 0;
 
 	cifs_dbg(FYI, "create/open\n");
 
@@ -906,55 +1004,47 @@ SMB2_open(const unsigned int xid, struct cifs_tcon *tcon, __le16 *path,
 	if (rc)
 		return rc;
 
+	if (oparms->create_options & CREATE_OPTION_READONLY)
+		file_attributes |= ATTR_READONLY;
+
 	req->ImpersonationLevel = IL_IMPERSONATION;
-	req->DesiredAccess = cpu_to_le32(desired_access);
+	req->DesiredAccess = cpu_to_le32(oparms->desired_access);
 	/* File attributes ignored on open (used in create though) */
 	req->FileAttributes = cpu_to_le32(file_attributes);
 	req->ShareAccess = FILE_SHARE_ALL_LE;
-	req->CreateDisposition = cpu_to_le32(create_disposition);
-	req->CreateOptions = cpu_to_le32(create_options);
+	req->CreateDisposition = cpu_to_le32(oparms->disposition);
+	req->CreateOptions = cpu_to_le32(oparms->create_options & CREATE_OPTIONS_MASK);
 	uni_path_len = (2 * UniStrnlen((wchar_t *)path, PATH_MAX)) + 2;
-	req->NameOffset = cpu_to_le16(sizeof(struct smb2_create_req)
-			- 8 /* pad */ - 4 /* do not count rfc1001 len field */);
+	/* do not count rfc1001 len field */
+	req->NameOffset = cpu_to_le16(sizeof(struct smb2_create_req) - 4);
 
 	iov[0].iov_base = (char *)req;
 	/* 4 for rfc1002 length field */
 	iov[0].iov_len = get_rfc1002_length(req) + 4;
 
 	/* MUST set path len (NameLength) to 0 opening root of share */
-	if (uni_path_len >= 4) {
-		req->NameLength = cpu_to_le16(uni_path_len - 2);
-		/* -1 since last byte is buf[0] which is sent below (path) */
-		iov[0].iov_len--;
-		if (uni_path_len % 8 != 0) {
-			copy_size = uni_path_len / 8 * 8;
-			if (copy_size < uni_path_len)
-				copy_size += 8;
-
-			copy_path = kzalloc(copy_size, GFP_KERNEL);
-			if (!copy_path)
-				return -ENOMEM;
-			memcpy((char *)copy_path, (const char *)path,
-				uni_path_len);
-			uni_path_len = copy_size;
-			path = copy_path;
-		}
-
-		iov[1].iov_len = uni_path_len;
-		iov[1].iov_base = path;
-		/*
-		 * -1 since last byte is buf[0] which was counted in
-		 * smb2_buf_len.
-		 */
-		inc_rfc1001_len(req, uni_path_len - 1);
-	} else {
-		iov[0].iov_len += 7;
-		req->hdr.smb2_buf_length = cpu_to_be32(be32_to_cpu(
-				req->hdr.smb2_buf_length) + 8 - 1);
-		num_iovecs = 1;
-		req->NameLength = 0;
+	req->NameLength = cpu_to_le16(uni_path_len - 2);
+	/* -1 since last byte is buf[0] which is sent below (path) */
+	iov[0].iov_len--;
+	if (uni_path_len % 8 != 0) {
+		copy_size = uni_path_len / 8 * 8;
+		if (copy_size < uni_path_len)
+			copy_size += 8;
+
+		copy_path = kzalloc(copy_size, GFP_KERNEL);
+		if (!copy_path)
+			return -ENOMEM;
+		memcpy((char *)copy_path, (const char *)path,
+			uni_path_len);
+		uni_path_len = copy_size;
+		path = copy_path;
 	}
 
+	iov[1].iov_len = uni_path_len;
+	iov[1].iov_base = path;
+	/* -1 since last byte is buf[0] which was counted in smb2_buf_len */
+	inc_rfc1001_len(req, uni_path_len - 1);
+
 	if (!server->oplocks)
 		*oplock = SMB2_OPLOCK_LEVEL_NONE;
 
@@ -962,21 +1052,29 @@ SMB2_open(const unsigned int xid, struct cifs_tcon *tcon, __le16 *path,
 	    *oplock == SMB2_OPLOCK_LEVEL_NONE)
 		req->RequestedOplockLevel = *oplock;
 	else {
-		iov[num_iovecs].iov_base = create_lease_buf(oplock+1, *oplock);
-		if (iov[num_iovecs].iov_base == NULL) {
+		rc = add_lease_context(iov, &num_iovecs, oplock);
+		if (rc) {
 			cifs_small_buf_release(req);
 			kfree(copy_path);
-			return -ENOMEM;
+			return rc;
+		}
+	}
+
+	if (*oplock == SMB2_OPLOCK_LEVEL_BATCH) {
+		/* need to set Next field of lease context if we request it */
+		if (tcon->ses->server->capabilities & SMB2_GLOBAL_CAP_LEASING) {
+			struct create_context *ccontext =
+			    (struct create_context *)iov[num_iovecs-1].iov_base;
+			ccontext->Next =
+				cpu_to_le32(sizeof(struct create_lease));
+		}
+		rc = add_durable_context(iov, &num_iovecs, oparms);
+		if (rc) {
+			cifs_small_buf_release(req);
+			kfree(copy_path);
+			kfree(iov[num_iovecs-1].iov_base);
+			return rc;
 		}
-		iov[num_iovecs].iov_len = sizeof(struct create_lease);
-		req->RequestedOplockLevel = SMB2_OPLOCK_LEVEL_LEASE;
-		req->CreateContextsOffset = cpu_to_le32(
-			sizeof(struct smb2_create_req) - 4 - 8 +
-			iov[num_iovecs-1].iov_len);
-		req->CreateContextsLength = cpu_to_le32(
-			sizeof(struct create_lease));
-		inc_rfc1001_len(&req->hdr, sizeof(struct create_lease));
-		num_iovecs++;
 	}
 
 	rc = SendReceive2(xid, ses, iov, num_iovecs, &resp_buftype, 0);
@@ -987,8 +1085,8 @@ SMB2_open(const unsigned int xid, struct cifs_tcon *tcon, __le16 *path,
 		goto creat_exit;
 	}
 
-	*persistent_fid = rsp->PersistentFileId;
-	*volatile_fid = rsp->VolatileFileId;
+	oparms->fid->persistent_fid = rsp->PersistentFileId;
+	oparms->fid->volatile_fid = rsp->VolatileFileId;
 
 	if (buf) {
 		memcpy(buf, &rsp->CreationTime, 32);