yaffsfs.c: Fix NULL dereference in yaffs_unmount2_reldev()

[yaffs2.git] / direct / yaffsfs.c

diff --git a/direct/yaffsfs.c b/direct/yaffsfs.c
index 7647444699f56d7e8cdf88cac1f01b05df511b98..823f7edcfc21c9dd7e2247e1da8781e8a74eb7e1 100644 (file)
--- a/direct/yaffsfs.c
+++ b/direct/yaffsfs.c
@@ -1,8 +1,7 @@
 /*
  * YAFFS: Yet Another Flash File System. A NAND-flash specific file system.
  *
- * Copyright (C) 2002-2011 Aleph One Ltd.
- *   for Toby Churchill Ltd and Brightstar Engineering
+ * Copyright (C) 2002-2018 Aleph One Ltd.
  *
  * Created by Charles Manning <charles@aleph1.co.uk>
  *
@@ -893,12 +892,14 @@ int yaffs_open_sharing_reldir(struct yaffs_obj *reldir, const YCHAR *path,
                        is_dir = (obj->variant_type ==
                                        YAFFS_OBJECT_TYPE_DIRECTORY);
 
-                       /* A directory can't be opened except for read */
-                       if ( is_dir &&
-                           (writeRequested || !readRequested || rwflags != O_RDONLY)) {
-                               openDenied = __LINE__;
-                               yaffsfs_SetError(-EISDIR);
-                               errorReported = __LINE__;
+                       /*
+                        * A directory can't be opened except for read, so we
+                        * ignore other flags
+                        */
+                       if (is_dir) {
+                               writeRequested = 0;
+                               readRequested = 1;
+                               rwflags = O_RDONLY;
                        }
 
                        if(is_dir) {
@@ -1942,17 +1943,21 @@ static int yaffsfs_DoUtime(struct yaffs_obj *obj,
        }
 
 #if !CONFIG_YAFFS_WINCE
+       // if the the buffer is null then create one with the fields set to the current time.
        if (!buf) {
                local.actime = Y_CURRENT_TIME;
                local.modtime = local.actime;
                buf = &local;
        }
 
+       // copy the buffer's time into the obj.
        if (obj) {
                int result;
 
                obj->yst_atime = buf->actime;
                obj->yst_mtime = buf->modtime;
+
+               // set the obj to dirty to cause it to be written to flash during the next flush operation.
                obj->dirty = 1;
                result = yaffs_flush_file(obj, 0, 0, 0);
                retVal = result == YAFFS_OK ? 0 : -1;
@@ -3049,6 +3054,7 @@ int yaffs_remount_common(struct yaffs_dev *dev, const YCHAR *path,
                       int force, int read_only)
 {
        int retVal = -1;
+       int was_read_only;
 
        if (yaffsfs_CheckMemRegion(path, 0, 0) < 0) {
                yaffsfs_SetError(-EFAULT);
@@ -3071,7 +3077,11 @@ int yaffs_remount_common(struct yaffs_dev *dev, const YCHAR *path,
                        if (force || !yaffsfs_IsDevBusy(dev)) {
                                if (read_only)
                                        yaffs_checkpoint_save(dev);
+                               was_read_only = dev->read_only;
                                dev->read_only = read_only ? 1 : 0;
+                               if (was_read_only && !read_only) {
+                                       yaffs_guts_cleanup(dev);
+                               }
                                retVal = 0;
                        } else
                                yaffsfs_SetError(-EBUSY);
@@ -3100,14 +3110,17 @@ int yaffs_unmount2_common(struct yaffs_dev *dev, const YCHAR *path, int force)
 {
        int retVal = -1;
 
-       if (yaffsfs_CheckMemRegion(path, 0, 0) < 0) {
-               yaffsfs_SetError(-EFAULT);
-               return -1;
-       }
 
-       if (yaffsfs_CheckPath(path) < 0) {
-               yaffsfs_SetError(-ENAMETOOLONG);
-               return -1;
+       if (!dev) {
+               if (yaffsfs_CheckMemRegion(path, 0, 0) < 0) {
+                       yaffsfs_SetError(-EFAULT);
+                       return -1;
+               }
+
+               if (yaffsfs_CheckPath(path) < 0) {
+                       yaffsfs_SetError(-ENAMETOOLONG);
+                       return -1;
+               }
        }
 
        yaffsfs_Lock();
@@ -3635,7 +3648,7 @@ struct yaffs_dirent *yaffs_readdir_fd(int fd)
 
        yaffsfs_Lock();
        f = yaffsfs_HandleToFileDes(fd);
-       if(f && f->isDir)
+       if(f && f->isDir && f->v.dir)
                ret = yaffsfs_readdir_no_lock(f->v.dir);
        yaffsfs_Unlock();
        return ret;