| Message ID | AM6PR03MB5170FFDE1D7BF09DD2663EDEE4F50@AM6PR03MB5170.eurprd03.prod.outlook.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Infrastructure to allow fixing exec deadlocks | expand |
On Fri, Mar 20, 2020 at 09:27:05PM +0100, Bernd Edlinger wrote: > This changes kcmp_epoll_target to use the new exec_update_mutex > instead of cred_guard_mutex. > > This should be safe, as the credentials are only used for reading, > and furthermore ->mm and ->sighand are updated on execve, > but only under the new exec_update_mutex. > > Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de> Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
diff --git a/kernel/kcmp.c b/kernel/kcmp.c index a0e3d7a..b3ff928 100644 --- a/kernel/kcmp.c +++ b/kernel/kcmp.c @@ -173,8 +173,8 @@ static int kcmp_epoll_target(struct task_struct *task1, /* * One should have enough rights to inspect task details. */ - ret = kcmp_lock(&task1->signal->cred_guard_mutex, - &task2->signal->cred_guard_mutex); + ret = kcmp_lock(&task1->signal->exec_update_mutex, + &task2->signal->exec_update_mutex); if (ret) goto err; if (!ptrace_may_access(task1, PTRACE_MODE_READ_REALCREDS) || @@ -229,8 +229,8 @@ static int kcmp_epoll_target(struct task_struct *task1, } err_unlock: - kcmp_unlock(&task1->signal->cred_guard_mutex, - &task2->signal->cred_guard_mutex); + kcmp_unlock(&task1->signal->exec_update_mutex, + &task2->signal->exec_update_mutex); err: put_task_struct(task1); put_task_struct(task2);
This changes kcmp_epoll_target to use the new exec_update_mutex instead of cred_guard_mutex. This should be safe, as the credentials are only used for reading, and furthermore ->mm and ->sighand are updated on execve, but only under the new exec_update_mutex. Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de> --- kernel/kcmp.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)