[PATCH] autofs: don't stuck in a loop if vfs_write returns an error

[Ian Kent]

From: Andrey Vagin <avagin@xxxxxxxxxx>

__vfs_write() returns a negative value in a error case.

Signed-off-by: Andrey Vagin <avagin@xxxxxxxxxx>
Signed-off-by: Ian Kent <raven@xxxxxxxxxx>
---
 fs/autofs4/waitq.c |    7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/fs/autofs4/waitq.c b/fs/autofs4/waitq.c
index 0146d91..631f155 100644
--- a/fs/autofs4/waitq.c
+++ b/fs/autofs4/waitq.c
@@ -66,11 +66,12 @@ static int autofs4_write(struct autofs_sb_info *sbi,
 	set_fs(KERNEL_DS);
 
 	mutex_lock(&sbi->pipe_mutex);
-	wr = __vfs_write(file, data, bytes, &file->f_pos);
-	while (bytes && wr) {
+	while (bytes) {
+		wr = __vfs_write(file, data, bytes, &file->f_pos);
+		if (wr <= 0)
+			break;
 		data += wr;
 		bytes -= wr;
-		wr = __vfs_write(file, data, bytes, &file->f_pos);
 	}
 	mutex_unlock(&sbi->pipe_mutex);