oom: fix oom_adjust_write() input sanity check
Andrew Morton pointed out oom_adjust_write() has very strange EIO
and new line handling. this patch fixes it.
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/proc/base.c b/fs/proc/base.c
index 71a3425..55c4c80 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1021,21 +1021,24 @@
size_t count, loff_t *ppos)
{
struct task_struct *task;
- char buffer[PROC_NUMBUF], *end;
- int oom_adjust;
+ char buffer[PROC_NUMBUF];
+ long oom_adjust;
unsigned long flags;
+ int err;
memset(buffer, 0, sizeof(buffer));
if (count > sizeof(buffer) - 1)
count = sizeof(buffer) - 1;
if (copy_from_user(buffer, buf, count))
return -EFAULT;
- oom_adjust = simple_strtol(buffer, &end, 0);
+
+ err = strict_strtol(strstrip(buffer), 0, &oom_adjust);
+ if (err)
+ return -EINVAL;
if ((oom_adjust < OOM_ADJUST_MIN || oom_adjust > OOM_ADJUST_MAX) &&
oom_adjust != OOM_DISABLE)
return -EINVAL;
- if (*end == '\n')
- end++;
+
task = get_proc_task(file->f_path.dentry->d_inode);
if (!task)
return -ESRCH;
@@ -1054,9 +1057,8 @@
unlock_task_sighand(task, &flags);
put_task_struct(task);
- if (end - buffer == 0)
- return -EIO;
- return end - buffer;
+
+ return count;
}
static const struct file_operations proc_oom_adjust_operations = {