From: Oleg Nesterov <oleg@xxxxxxxxxx> commit 46ef2be0d1d5ccea0c41bb606143586daadd537c upstream. tracing_buffers_open() is racy, the memory inode->i_private points to can be already freed. Change debugfs_create_file("trace_pipe_raw", data) caller to pass "data = tr", tracing_buffers_open() can use tracing_get_cpu(). Change debugfs_create_file("snapshot_raw_fops", data) caller too, this file uses tracing_buffers_open/release. Link: http://lkml.kernel.org/r/20130723152600.GA23720@xxxxxxxxxx Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx> Signed-off-by: Steven Rostedt <rostedt@xxxxxxxxxxx> --- kernel/trace/trace.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 8e8bb0e..7dcd673 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -4941,8 +4941,7 @@ static const struct file_operations snapshot_raw_fops = { 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 trace_array *tr = inode->i_private; struct ftrace_buffer_info *info; int ret; @@ -4961,7 +4960,7 @@ static int tracing_buffers_open(struct inode *inode, struct file *filp) mutex_lock(&trace_types_lock); info->iter.tr = tr; - info->iter.cpu_file = tc->cpu; + info->iter.cpu_file = tracing_get_cpu(inode); info->iter.trace = tr->current_trace; info->iter.trace_buffer = &tr->trace_buffer; info->spare = NULL; @@ -5568,7 +5567,7 @@ tracing_init_debugfs_percpu(struct trace_array *tr, long cpu) &data->trace_cpu, cpu, &tracing_fops); trace_create_cpu_file("trace_pipe_raw", 0444, d_cpu, - &data->trace_cpu, cpu, &tracing_buffers_fops); + tr, cpu, &tracing_buffers_fops); trace_create_cpu_file("stats", 0444, d_cpu, &data->trace_cpu, cpu, &tracing_stats_fops); @@ -5581,7 +5580,7 @@ tracing_init_debugfs_percpu(struct trace_array *tr, long cpu) &data->trace_cpu, cpu, &snapshot_fops); trace_create_cpu_file("snapshot_raw", 0444, d_cpu, - &data->trace_cpu, cpu, &snapshot_raw_fops); + tr, cpu, &snapshot_raw_fops); #endif } -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html