From 82244b169ed2eee1ef7f97a3a6693f5a6eff8a69 Mon Sep 17 00:00:00 2001 From: Oliver Neukum Date: Tue, 2 Jan 2007 08:48:08 +0100 Subject: [PATCH] sysfs: error handling in sysfs, fill_read_buffer() if a driver returns an error in fill_read_buffer(), the buffer will be marked as filled. Subsequent reads will return eof. But there is no data because of an error, not because it has been read. Not marking the buffer filled is the obvious fix. Signed-off-by: Oliver Neukum Signed-off-by: Greg Kroah-Hartman --- fs/sysfs/file.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c index 46618f81ae48..c0e117649a4d 100644 --- a/fs/sysfs/file.c +++ b/fs/sysfs/file.c @@ -83,7 +83,8 @@ remove_from_collection(struct sysfs_buffer *buffer, struct inode *node) * Allocate @buffer->page, if it hasn't been already, then call the * kobject's show() method to fill the buffer with this attribute's * data. - * This is called only once, on the file's first read. + * This is called only once, on the file's first read unless an error + * is returned. */ static int fill_read_buffer(struct dentry * dentry, struct sysfs_buffer * buffer) { @@ -101,12 +102,13 @@ static int fill_read_buffer(struct dentry * dentry, struct sysfs_buffer * buffer buffer->event = atomic_read(&sd->s_event); count = ops->show(kobj,attr,buffer->page); - buffer->needs_read_fill = 0; BUG_ON(count > (ssize_t)PAGE_SIZE); - if (count >= 0) + if (count >= 0) { + buffer->needs_read_fill = 0; buffer->count = count; - else + } else { ret = count; + } return ret; } -- 2.20.1