From: Dan Carpenter <dan.carpenter@oracle.com>
To: Mike Marshall <hubcap@omnibond.com>
Cc: linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org
Subject: [PATCH] orangefs: handle zero size write in debugfs
Date: Fri, 14 Apr 2017 19:11:53 +0000 [thread overview]
Message-ID: <20170414191153.GB30875@mwanda> (raw)
If we write zero bytes to this debugfs file, then it will cause an
underflow when we do copy_from_user(buf, ubuf, count - 1). Debugfs can
normally only be written to by root so the impact of this is low.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
diff --git a/fs/orangefs/orangefs-debugfs.c b/fs/orangefs/orangefs-debugfs.c
index 791912da97d7..716ed337f166 100644
--- a/fs/orangefs/orangefs-debugfs.c
+++ b/fs/orangefs/orangefs-debugfs.c
@@ -440,6 +440,9 @@ static ssize_t orangefs_debug_write(struct file *file,
"orangefs_debug_write: %pD\n",
file);
+ if (count = 0)
+ return 0;
+
/*
* Thwart users who try to jamb a ridiculous number
* of bytes into the debug file...
reply other threads:[~2017-04-14 19:11 UTC|newest]
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