Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull VFS fixes from Al Viro:
 "A bunch of assorted fixes, most of them followups to overlayfs merge"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  ovl: initialize ->is_cursor
  Return short read or 0 at end of a raw device, not EIO
  isofs: don't bother with ->d_op for normal case
  isofs_cmp(): we'll never see a dentry for . or ..
  overlayfs: fix lockdep misannotation
  ovl: fix check for cursor
  overlayfs: barriers for opening upper-layer directory
  rcu: Provide counterpart to rcu_dereference() for non-RCU situations
  staging: android: logger: Fix log corruption regression

2 files changed, 9 insertions, 6 deletions

diff --git a/drivers/char/raw.c b/drivers/char/raw.c
index 0102dc788608..a24891b97547 100644
--- a/drivers/char/raw.c
+++ b/drivers/char/raw.c
@@ -285,7 +285,7 @@ static long raw_ctl_compat_ioctl(struct file *file, unsigned int cmd,
 
 static const struct file_operations raw_fops = {
 	.read		= new_sync_read,
-	.read_iter	= generic_file_read_iter,
+	.read_iter	= blkdev_read_iter,
 	.write		= new_sync_write,
 	.write_iter	= blkdev_write_iter,
 	.fsync		= blkdev_fsync,
diff --git a/drivers/staging/android/logger.c b/drivers/staging/android/logger.c
index 28b93d39a94e..a673ffa34aa3 100644
--- a/drivers/staging/android/logger.c
+++ b/drivers/staging/android/logger.c
@@ -420,7 +420,7 @@ static ssize_t logger_write_iter(struct kiocb *iocb, struct iov_iter *from)
 	struct logger_log *log = file_get_log(iocb->ki_filp);
 	struct logger_entry header;
 	struct timespec now;
-	size_t len, count;
+	size_t len, count, w_off;
 
 	count = min_t(size_t, iocb->ki_nbytes, LOGGER_ENTRY_MAX_PAYLOAD);
 
@@ -452,11 +452,14 @@ static ssize_t logger_write_iter(struct kiocb *iocb, struct iov_iter *from)
 	memcpy(log->buffer + log->w_off, &header, len);
 	memcpy(log->buffer, (char *)&header + len, sizeof(header) - len);
 
-	len = min(count, log->size - log->w_off);
+	/* Work with a copy until we are ready to commit the whole entry */
+	w_off =  logger_offset(log, log->w_off + sizeof(struct logger_entry));
 
-	if (copy_from_iter(log->buffer + log->w_off, len, from) != len) {
+	len = min(count, log->size - w_off);
+
+	if (copy_from_iter(log->buffer + w_off, len, from) != len) {
 		/*
-		 * Note that by not updating w_off, this abandons the
+		 * Note that by not updating log->w_off, this abandons the
 		 * portion of the new entry that *was* successfully
 		 * copied, just above.  This is intentional to avoid
 		 * message corruption from missing fragments.
@@ -470,7 +473,7 @@ static ssize_t logger_write_iter(struct kiocb *iocb, struct iov_iter *from)
 		return -EFAULT;
 	}
 
-	log->w_off = logger_offset(log, log->w_off + count);
+	log->w_off = logger_offset(log, w_off + count);
 	mutex_unlock(&log->mutex);
 
 	/* wake up any blocked readers */