diff options
| author | Oleg Nesterov <oleg@redhat.com> | 2013-07-23 17:26:03 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-08-29 09:47:32 -0700 |
| commit | 6dafb0f13798c998ec344bf910b2d89c51961481 (patch) | |
| tree | 81b45e5ef0f224801d09f6453199d39b4c6b7412 /kernel/trace | |
| parent | 92b6279e284257fb7908bf4d24956f5af13aaa2d (diff) | |
tracing: Change tracing_stats_fops to rely on tracing_get_cpu()
commit 4d3435b8a4c3357695e09c5e7a3bf73a19fca5b0 upstream.
tracing_open_generic_tc() is racy, the memory inode->i_private
points to can be already freed.
1. Change one of its users, tracing_stats_fops, to use
tracing_*_generic_tr() instead.
2. Change trace_create_cpu_file("stats", data) to pass "data = tr".
3. Change tracing_stats_read() to use tracing_get_cpu().
Link: http://lkml.kernel.org/r/20130723152603.GA23727@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'kernel/trace')
| -rw-r--r-- | kernel/trace/trace.c | 13 |
1 files changed, 6 insertions, 7 deletions
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 7dcd67332f5..801d72b84a2 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -2973,7 +2973,6 @@ int tracing_open_generic_tr(struct inode *inode, struct file *filp) filp->private_data = inode->i_private; return 0; - } int tracing_open_generic_tc(struct inode *inode, struct file *filp) @@ -5277,14 +5276,14 @@ static ssize_t tracing_stats_read(struct file *filp, char __user *ubuf, size_t count, loff_t *ppos) { - struct trace_cpu *tc = filp->private_data; - struct trace_array *tr = tc->tr; + struct inode *inode = file_inode(filp); + struct trace_array *tr = inode->i_private; struct trace_buffer *trace_buf = &tr->trace_buffer; + int cpu = tracing_get_cpu(inode); struct trace_seq *s; unsigned long cnt; unsigned long long t; unsigned long usec_rem; - int cpu = tc->cpu; s = kmalloc(sizeof(*s), GFP_KERNEL); if (!s) @@ -5337,10 +5336,10 @@ tracing_stats_read(struct file *filp, char __user *ubuf, } static const struct file_operations tracing_stats_fops = { - .open = tracing_open_generic_tc, + .open = tracing_open_generic_tr, .read = tracing_stats_read, .llseek = generic_file_llseek, - .release = tracing_release_generic_tc, + .release = tracing_release_generic_tr, }; #ifdef CONFIG_DYNAMIC_FTRACE @@ -5570,7 +5569,7 @@ tracing_init_debugfs_percpu(struct trace_array *tr, long cpu) tr, cpu, &tracing_buffers_fops); trace_create_cpu_file("stats", 0444, d_cpu, - &data->trace_cpu, cpu, &tracing_stats_fops); + tr, cpu, &tracing_stats_fops); trace_create_cpu_file("buffer_size_kb", 0444, d_cpu, &data->trace_cpu, cpu, &tracing_entries_fops); |