lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

tracing: fix a typo in tracing_cpumask_write()

Browse Source 
It's tracing_cpumask_new that should be kfree()ed.

This causes tracing_cpumask to be freed due to the typo:

 # echo z > tracing_cpumask
 bash: echo: write error: Invalid argument

And subsequent reads/writes to tracing_cpuamsk will access this
already-freed tracing_cpumask, thus may lead to crash.

[ Impact: fix leak and crash when writing invalid val to tracing_cpumask ]

Acked-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
LKML-Reference: <4A35B86A.7070608@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This commit is contained in:
Li Zefan
2009-06-15 10:56:42 +08:00
committed by Steven Rostedt
parent 78be6914cb
commit 215368e8e5
1 changed files with 3 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
kernel/trace/trace.c
View File

@@ -2191,11 +2191,12 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf,
if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL))
return -ENOMEM; return -ENOMEM;
mutex_lock(&tracing_cpumask_update_lock);
err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); err = cpumask_parse_user(ubuf, count, tracing_cpumask_new);
if (err) if (err)
goto err_unlock; goto err_unlock;
mutex_lock(&tracing_cpumask_update_lock);
local_irq_disable(); local_irq_disable();
__raw_spin_lock(&ftrace_max_lock); __raw_spin_lock(&ftrace_max_lock);
for_each_tracing_cpu(cpu) { for_each_tracing_cpu(cpu) {
@@ -2223,8 +2224,7 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf,
return count; return count;
err_unlock: err_unlock:
mutex_unlock(&tracing_cpumask_update_lock); free_cpumask_var(tracing_cpumask_new);
free_cpumask_var(tracing_cpumask);
return err; return err;
} }