Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 7b85af63 authored by Steven Rostedt (Red Hat)'s avatar Steven Rostedt (Red Hat) Committed by Steven Rostedt
Browse files

tracing: Get trace_array ref counts when accessing trace files 



When a trace file is opened that may access a trace array, it must
increment its ref count to prevent it from being deleted.

Cc: stable@vger.kernel.org # 3.10
Reported-by: default avatarAlexander Lam <azl@google.com>
Signed-off-by: default avatarSteven Rostedt <rostedt@goodmis.org>
parent ff451961

kernel/trace/trace.c

+112 −9
Original line number Diff line number Diff line
@@ -2965,6 +2965,43 @@ int tracing_open_generic(struct inode *inode, struct file *filp) 
	return 0;

}



/*

 * Open and update trace_array ref count.

 * Must have the current trace_array passed to it.

 */

int tracing_open_generic_tr(struct inode *inode, struct file *filp)

{

	struct trace_array *tr = inode->i_private;



	if (tracing_disabled)

		return -ENODEV;



	if (trace_array_get(tr) < 0)

		return -ENODEV;



	filp->private_data = inode->i_private;



	return 0;

	

}



int tracing_open_generic_tc(struct inode *inode, struct file *filp)

{

	struct trace_cpu *tc = inode->i_private;

	struct trace_array *tr = tc->tr;



	if (tracing_disabled)

		return -ENODEV;



	if (trace_array_get(tr) < 0)

		return -ENODEV;



	filp->private_data = inode->i_private;



	return 0;

	

}



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

{

	struct seq_file *m = file->private_data;
@@ -3008,6 +3045,32 @@ static int tracing_release(struct inode *inode, struct file *file) 
	return 0;

}



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

{

	struct trace_array *tr = inode->i_private;



	trace_array_put(tr);

	return 0;

}



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

{

	struct trace_cpu *tc = inode->i_private;

	struct trace_array *tr = tc->tr;



	trace_array_put(tr);

	return 0;

}



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

{

	struct trace_array *tr = inode->i_private;



	trace_array_put(tr);



	return single_release(inode, file);

}



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

{

	struct trace_cpu *tc = inode->i_private;
@@ -3394,9 +3457,14 @@ 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;



	if (tracing_disabled)

		return -ENODEV;



	if (trace_array_get(tr) < 0)

		return -ENODEV;



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

}
@@ -3404,7 +3472,7 @@ static const struct file_operations tracing_iter_fops = { 
	.open		= tracing_trace_options_open,

	.read		= seq_read,

	.llseek		= seq_lseek,

	.release	= single_release,

	.release	= tracing_single_release_tr,

	.write		= tracing_trace_options_write,

};
@@ -3892,6 +3960,9 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp) 
	if (tracing_disabled)

		return -ENODEV;



	if (trace_array_get(tr) < 0)

		return -ENODEV;



	mutex_lock(&trace_types_lock);



	/* create a buffer to store the information to pass to userspace */
@@ -3944,6 +4015,7 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp) 
fail:

	kfree(iter->trace);

	kfree(iter);

	__trace_array_put(tr);

	mutex_unlock(&trace_types_lock);

	return ret;

}
@@ -3951,6 +4023,8 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp) 
static int tracing_release_pipe(struct inode *inode, struct file *file)

{

	struct trace_iterator *iter = file->private_data;

	struct trace_cpu *tc = inode->i_private;

	struct trace_array *tr = tc->tr;



	mutex_lock(&trace_types_lock);
@@ -3964,6 +4038,8 @@ static int tracing_release_pipe(struct inode *inode, struct file *file) 
	kfree(iter->trace);

	kfree(iter);



	trace_array_put(tr);



	return 0;

}
@@ -4421,6 +4497,8 @@ tracing_free_buffer_release(struct inode *inode, struct file *filp) 
	/* resize the ring buffer to 0 */

	tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS);



	trace_array_put(tr);



	return 0;

}
@@ -4597,10 +4675,20 @@ static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, 


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

{

	struct trace_array *tr = inode->i_private;

	int ret;



	if (tracing_disabled)

		return -ENODEV;



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

	if (trace_array_get(tr))

		return -ENODEV;



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

	if (ret < 0)

		trace_array_put(tr);



	return ret;

}



struct ftrace_buffer_info {
@@ -4796,34 +4884,38 @@ static const struct file_operations tracing_pipe_fops = { 
};



static const struct file_operations tracing_entries_fops = {

	.open		= tracing_open_generic,

	.open		= tracing_open_generic_tc,

	.read		= tracing_entries_read,

	.write		= tracing_entries_write,

	.llseek		= generic_file_llseek,

	.release	= tracing_release_generic_tc,

};



static const struct file_operations tracing_total_entries_fops = {

	.open		= tracing_open_generic,

	.open		= tracing_open_generic_tr,

	.read		= tracing_total_entries_read,

	.llseek		= generic_file_llseek,

	.release	= tracing_release_generic_tr,

};



static const struct file_operations tracing_free_buffer_fops = {

	.open		= tracing_open_generic_tr,

	.write		= tracing_free_buffer_write,

	.release	= tracing_free_buffer_release,

};



static const struct file_operations tracing_mark_fops = {

	.open		= tracing_open_generic,

	.open		= tracing_open_generic_tr,

	.write		= tracing_mark_write,

	.llseek		= generic_file_llseek,

	.release	= tracing_release_generic_tr,

};



static const struct file_operations trace_clock_fops = {

	.open		= tracing_clock_open,

	.read		= seq_read,

	.llseek		= seq_lseek,

	.release	= single_release,

	.release	= tracing_single_release_tr,

	.write		= tracing_clock_write,

};
@@ -4851,13 +4943,19 @@ static int tracing_buffers_open(struct inode *inode, struct file *filp) 
	struct trace_cpu *tc = inode->i_private;

	struct trace_array *tr = tc->tr;

	struct ftrace_buffer_info *info;

	int ret;



	if (tracing_disabled)

		return -ENODEV;



	if (trace_array_get(tr) < 0)

		return -ENODEV;



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

	if (!info)

	if (!info) {

		trace_array_put(tr);

		return -ENOMEM;

	}



	mutex_lock(&trace_types_lock);
@@ -4875,7 +4973,11 @@ static int tracing_buffers_open(struct inode *inode, struct file *filp) 


	mutex_unlock(&trace_types_lock);



	return nonseekable_open(inode, filp);

	ret = nonseekable_open(inode, filp);

	if (ret < 0)

		trace_array_put(tr);



	return ret;

}



static unsigned int
@@ -5765,9 +5867,10 @@ rb_simple_write(struct file *filp, const char __user *ubuf, 
}



static const struct file_operations rb_simple_fops = {

	.open		= tracing_open_generic,

	.open		= tracing_open_generic_tr,

	.read		= rb_simple_read,

	.write		= rb_simple_write,

	.release	= tracing_release_generic_tr,

	.llseek		= default_llseek,

};