cifs: fix oplock request handling in posix codepath

cifs_posix_open takes a "poplock" argument that's intended to be used in
the actual posix open call to set the "Flags" field. It ignores this
value however and declares an "oplock" parameter on the stack that it
passes uninitialized to the CIFSPOSIXOpen function. Not only does this
mean that the oplock request flags are bogus, but the result that's
expected to be in that variable is unchanged.

Fix this, and also clean up the type of the oplock parameter used. Since
it's expected to be __u32, we should use that everywhere and not
implicitly cast it from a signed type.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>

fs/cifs/cifsproto.h

@@ -97,7 +97,7 @@ extern struct timespec cnvrtDosUnixTm(__le16 le_date, __le16 le_time,
 
 extern int cifs_posix_open(char *full_path, struct inode **pinode,
 			   struct super_block *sb, int mode, int oflags,
-			   int *poplock, __u16 *pnetfid, int xid);
+			   __u32 *poplock, __u16 *pnetfid, int xid);
 extern void cifs_unix_basic_to_fattr(struct cifs_fattr *fattr,
 				     FILE_UNIX_BASIC_INFO *info,
 				     struct cifs_sb_info *cifs_sb);

fs/cifs/dir.c

@@ -180,10 +180,9 @@ cifs_fill_fileinfo(struct inode *newinode, __u16 fileHandle,
 
 int cifs_posix_open(char *full_path, struct inode **pinode,
 		    struct super_block *sb, int mode, int oflags,
-		    int *poplock, __u16 *pnetfid, int xid)
+		    __u32 *poplock, __u16 *pnetfid, int xid)
 {
 	int rc;
-	__u32 oplock;
 	bool write_only = false;
 	FILE_UNIX_BASIC_INFO *presp_data;
 	__u32 posix_flags = 0;
@@ -228,7 +227,7 @@ int cifs_posix_open(char *full_path, struct inode **pinode,
 
 	mode &= ~current_umask();
 	rc = CIFSPOSIXCreate(xid, cifs_sb->tcon, posix_flags, mode,
-			pnetfid, presp_data, &oplock, full_path,
+			pnetfid, presp_data, poplock, full_path,
 			cifs_sb->local_nls, cifs_sb->mnt_cifs_flags &
 					CIFS_MOUNT_MAP_SPECIAL_CHR);
 	if (rc)
@@ -280,7 +279,7 @@ cifs_create(struct inode *inode, struct dentry *direntry, int mode,
 	int rc = -ENOENT;
 	int xid;
 	int create_options = CREATE_NOT_DIR;
-	int oplock = 0;
+	__u32 oplock = 0;
 	int oflags;
 	bool posix_create = false;
 	/*
@@ -611,7 +610,7 @@ cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
 {
 	int xid;
 	int rc = 0; /* to get around spurious gcc warning, set to zero here */
-	int oplock = 0;
+	__u32 oplock = 0;
 	__u16 fileHandle = 0;
 	bool posix_open = false;
 	struct cifs_sb_info *cifs_sb;

fs/cifs/file.c

@@ -123,9 +123,11 @@ static inline int cifs_get_disposition(unsigned int flags)
 }
 
 /* all arguments to this function must be checked for validity in caller */
-static inline int cifs_posix_open_inode_helper(struct inode *inode,
-			struct file *file, struct cifsInodeInfo *pCifsInode,
-			struct cifsFileInfo *pCifsFile, int oplock, u16 netfid)
+static inline int
+cifs_posix_open_inode_helper(struct inode *inode, struct file *file,
+			     struct cifsInodeInfo *pCifsInode,
+			     struct cifsFileInfo *pCifsFile, __u32 oplock,
+			     u16 netfid)
 {
 
 	write_lock(&GlobalSMBSeslock);
@@ -279,7 +281,8 @@ client_can_cache:
 int cifs_open(struct inode *inode, struct file *file)
 {
 	int rc = -EACCES;
-	int xid, oplock;
+	int xid;
+	__u32 oplock;
 	struct cifs_sb_info *cifs_sb;
 	struct cifsTconInfo *tcon;
 	struct cifsFileInfo *pCifsFile;
@@ -474,7 +477,8 @@ static int cifs_relock_file(struct cifsFileInfo *cifsFile)
 static int cifs_reopen_file(struct file *file, bool can_flush)
 {
 	int rc = -EACCES;
-	int xid, oplock;
+	int xid;
+	__u32 oplock;
 	struct cifs_sb_info *cifs_sb;
 	struct cifsTconInfo *tcon;
 	struct cifsFileInfo *pCifsFile;