mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-10 20:44:09 +08:00
rcu-tasks: Don't delete holdouts within trc_inspect_reader()
As Yanfei pointed out, although invoking trc_del_holdout() is safe from the viewpoint of the integrity of the holdout list itself, the put_task_struct() invoked by trc_del_holdout() can result in use-after-free errors due to later accesses to this task_struct structure by the RCU Tasks Trace grace-period kthread. This commit therefore removes this call to trc_del_holdout() from trc_inspect_reader() in favor of the grace-period thread's existing call to trc_del_holdout(), thus eliminating that particular class of use-after-free errors. Reported-by: "Xu, Yanfei" <yanfei.xu@windriver.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit is contained in:
parent
05bc276cf2
commit
1d10bf55d8
@ -953,10 +953,9 @@ static bool trc_inspect_reader(struct task_struct *t, void *arg)
|
|||||||
in_qs = likely(!t->trc_reader_nesting);
|
in_qs = likely(!t->trc_reader_nesting);
|
||||||
}
|
}
|
||||||
|
|
||||||
// Mark as checked. Because this is called from the grace-period
|
// Mark as checked so that the grace-period kthread will
|
||||||
// kthread, also remove the task from the holdout list.
|
// remove it from the holdout list.
|
||||||
t->trc_reader_checked = true;
|
t->trc_reader_checked = true;
|
||||||
trc_del_holdout(t);
|
|
||||||
|
|
||||||
if (in_qs)
|
if (in_qs)
|
||||||
return true; // Already in quiescent state, done!!!
|
return true; // Already in quiescent state, done!!!
|
||||||
|
Loading…
Reference in New Issue
Block a user