Commit a996996d authored Jan 29, 2010 by Matt Mackall Committed by Herbert Xu Feb 02, 2010

random: drop weird m_time/a_time manipulation



No other driver does anything remotely like this that I know of except
for the tty drivers, and I can't see any reason for random/urandom to do
it. In fact, it's a (trivial, harmless) timing information leak. And
obviously, it generates power- and flash-cycle wasting I/O, especially
if combined with something like hwrngd. Also, it breaks ubifs's
expectations.

Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

parent 92dcffb9

drivers/char/random.c

+0 −8

Original line number	Diff line number	Diff line
		@@ -1051,12 +1051,6 @@ random_read(struct file file, char __user buf, size_t nbytes, loff_t *ppos)
		/* like a named pipe */
		}

		/*
		* If we gave the user some bytes, update the access time.
		*/
		if (count)
		file_accessed(file);

		return (count ? count : retval);
		}

		@@ -1116,8 +1110,6 @@ static ssize_t random_write(struct file file, const char __user buffer,
		if (ret)
		return ret;

		inode->i_mtime = current_fs_time(inode->i_sb);
		mark_inode_dirty(inode);
		return (ssize_t)count;
		}

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