Commit f77d09a3 authored by Alexander Z Lam's avatar Alexander Z Lam Committed by Steven Rostedt
Browse files

tracing: Miscellaneous fixes for trace_array ref counting 

Some error paths did not handle ref counting properly, and some trace files need
ref counting.

Link: http://lkml.kernel.org/r/1374171524-11948-1-git-send-email-azl@google.com



Cc: stable@vger.kernel.org # 3.10
Cc: Vaibhav Nagarnaik <vnagarnaik@google.com>
Cc: David Sharp <dhsharp@google.com>
Cc: Alexander Z Lam <lambchop468@gmail.com>
Signed-off-by: default avatarAlexander Z Lam <azl@google.com>
Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
parent 609e85a7

kernel/trace/trace.c

+18 −6
Original line number Diff line number Diff line
@@ -3008,7 +3008,6 @@ static int tracing_release(struct inode *inode, struct file *file) 


	iter = m->private;

	tr = iter->tr;

	trace_array_put(tr);



	mutex_lock(&trace_types_lock);
@@ -3023,6 +3022,9 @@ static int tracing_release(struct inode *inode, struct file *file) 
	if (!iter->snapshot)

		/* reenable tracing if it was previously enabled */

		tracing_start_tr(tr);



	__trace_array_put(tr);



	mutex_unlock(&trace_types_lock);



	mutex_destroy(&iter->mutex);
@@ -3447,6 +3449,7 @@ tracing_trace_options_write(struct file *filp, const char __user *ubuf, 
static int tracing_trace_options_open(struct inode *inode, struct file *file)

{

	struct trace_array *tr = inode->i_private;

	int ret;



	if (tracing_disabled)

		return -ENODEV;
@@ -3454,7 +3457,11 @@ static int tracing_trace_options_open(struct inode *inode, struct file *file) 
	if (trace_array_get(tr) < 0)

		return -ENODEV;



	return single_open(file, tracing_trace_options_show, inode->i_private);

	ret = single_open(file, tracing_trace_options_show, inode->i_private);

	if (ret < 0)

		trace_array_put(tr);



	return ret;

}



static const struct file_operations tracing_iter_fops = {
@@ -3958,6 +3965,7 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp) 
	iter = kzalloc(sizeof(*iter), GFP_KERNEL);

	if (!iter) {

		ret = -ENOMEM;

		__trace_array_put(tr);

		goto out;

	}
@@ -4704,21 +4712,24 @@ static int tracing_snapshot_open(struct inode *inode, struct file *file) 
			ret = PTR_ERR(iter);

	} else {

		/* Writes still need the seq_file to hold the private data */

		ret = -ENOMEM;

		m = kzalloc(sizeof(*m), GFP_KERNEL);

		if (!m)

			return -ENOMEM;

			goto out;

		iter = kzalloc(sizeof(*iter), GFP_KERNEL);

		if (!iter) {

			kfree(m);

			return -ENOMEM;

			goto out;

		}

		ret = 0;



		iter->tr = tr;

		iter->trace_buffer = &tc->tr->max_buffer;

		iter->cpu_file = tc->cpu;

		m->private = iter;

		file->private_data = m;

	}



out:

	if (ret < 0)

		trace_array_put(tr);
@@ -5328,9 +5339,10 @@ tracing_stats_read(struct file *filp, char __user *ubuf, 
}



static const struct file_operations tracing_stats_fops = {

	.open		= tracing_open_generic,

	.open		= tracing_open_generic_tc,

	.read		= tracing_stats_read,

	.llseek		= generic_file_llseek,

	.release	= tracing_release_generic_tc,

};



#ifdef CONFIG_DYNAMIC_FTRACE

kernel/trace/trace_events.c

+19 −2
Original line number Diff line number Diff line
@@ -1218,6 +1218,7 @@ show_header(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) 


static int ftrace_event_avail_open(struct inode *inode, struct file *file);

static int ftrace_event_set_open(struct inode *inode, struct file *file);

static int ftrace_event_release(struct inode *inode, struct file *file);



static const struct seq_operations show_event_seq_ops = {

	.start = t_start,
@@ -1245,7 +1246,7 @@ static const struct file_operations ftrace_set_event_fops = { 
	.read = seq_read,

	.write = ftrace_event_write,

	.llseek = seq_lseek,

	.release = seq_release,

	.release = ftrace_event_release,

};



static const struct file_operations ftrace_enable_fops = {
@@ -1323,6 +1324,15 @@ ftrace_event_open(struct inode *inode, struct file *file, 
	return ret;

}



static int ftrace_event_release(struct inode *inode, struct file *file)

{

	struct trace_array *tr = inode->i_private;



	trace_array_put(tr);



	return seq_release(inode, file);

}



static int

ftrace_event_avail_open(struct inode *inode, struct file *file)

{
@@ -1336,12 +1346,19 @@ ftrace_event_set_open(struct inode *inode, struct file *file) 
{

	const struct seq_operations *seq_ops = &show_set_event_seq_ops;

	struct trace_array *tr = inode->i_private;

	int ret;



	if (trace_array_get(tr) < 0)

		return -ENODEV;



	if ((file->f_mode & FMODE_WRITE) &&

	    (file->f_flags & O_TRUNC))

		ftrace_clear_events(tr);



	return ftrace_event_open(inode, file, seq_ops);

	ret = ftrace_event_open(inode, file, seq_ops);

	if (ret < 0)

		trace_array_put(tr);

	return ret;

}



static struct event_subsystem *

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