linux-kernel - [PATCH 21/28] sysfs: error handling in sysfs, fill_read

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <11708946903974-git-send-email-greg@kroah.com>
Date:	Wed,  7 Feb 2007 16:30:09 -0800
From:	Greg KH <greg@...ah.com>
To:	linux-kernel@...r.kernel.org
Cc:	Oliver Neukum <oliver@...kum.name>,
	Greg Kroah-Hartman <gregkh@...e.de>
Subject: [PATCH 21/28] sysfs: error handling in sysfs, fill_read_buffer()

From: Oliver Neukum <oliver@...kum.name>

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 <oliver@...kum.name>
Signed-off-by: Greg Kroah-Hartman <gregkh@...e.de>
---
 fs/sysfs/file.c |   10 ++++++----
 1 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/fs/sysfs/file.c b/fs/sysfs/file.c
index 46618f8..c0e1176 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;
 }
 
-- 
1.4.4.4

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/