From: Hillf Danton <hdanton@sina.com> mainline inclusion from mainline-v5.7-rc1 commit ae46d2aa6a7fbe8ca0946f24b061b6ccdc6c3f25 category: bugfix bugzilla: 47439 CVE: NA --------------------------- __get_user_pages_locked() will return 0 instead of -EINTR after commit 4426e945df588 ("mm/gup: allow VM_FAULT_RETRY for multiple times") which added extra code to allow gup detect fatal signal faster. Restore the original -EINTR behavior. Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Peter Zijlstra <peterz@infradead.org> Fixes: 4426e945df58 ("mm/gup: allow VM_FAULT_RETRY for multiple times") Reported-by: syzbot+3be1a33f04dc782e9fd5@syzkaller.appspotmail.com Signed-off-by: Hillf Danton <hdanton@sina.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Peter Xu <peterx@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> Reviewed-by: Jing Xiangfeng <jingxiangfeng@huawei.com> Reviewed-by: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Yang Yingliang <yangyingliang@huawei.com> Signed-off-by: Cheng Jian <cj.chengjian@huawei.com> --- mm/gup.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/mm/gup.c b/mm/gup.c index 8be20cbec785..83f0737e57a7 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -947,8 +947,11 @@ static __always_inline long __get_user_pages_locked(struct task_struct *tsk, * start trying again otherwise it can loop forever. */ - if (fatal_signal_pending(current)) + if (fatal_signal_pending(current)) { + if (!pages_done) + pages_done = -EINTR; break; + } *locked = 1; down_read(&mm->mmap_sem); -- 2.25.1