Hi Andrew, On Wed, Oct 19, 2016 at 11:33:27AM -0700, Andrew Morton wrote: > On Wed, 12 Oct 2016 10:57:03 +0100 Catalin Marinas <catalin.marinas@xxxxxxx> wrote: > > Commit 68f24b08ee89 ("sched/core: Free the stack early if > > CONFIG_THREAD_INFO_IN_TASK") may cause the task->stack to be freed > > during kmemleak_scan() execution, leading to either a NULL pointer > > fault (if task->stack is NULL) or kmemleak accessing already freed > > memory. This patch uses the new try_get_task_stack() API to ensure that > > the task stack is not freed during kmemleak stack scanning. > > > > Fixes: 68f24b08ee89 ("sched/core: Free the stack early if CONFIG_THREAD_INFO_IN_TASK") > > Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> > > Cc: Andy Lutomirski <luto@xxxxxxxxxx> > > Cc: CAI Qian <caiqian@xxxxxxxxxx> > > Reported-by: CAI Qian <caiqian@xxxxxxxxxx> > > Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx> > > I'll add > > Cc: <stable@xxxxxxxxxxxxxxx> [4.8.x] This should be 4.9.x. The commit that introduces try_get_task_stack() was merged in 4.9-rc1: c6c314a613cd ("sched/core: Add try_get_task_stack() and put_task_stack()"). -- Catalin -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx"> email@xxxxxxxxx </a>