From fc01d8c61ce02c034e67378cd3e645734bc18c8c Mon Sep 17 00:00:00 2001 From: Paul Fulghum Date: Tue, 1 Jan 2019 12:28:53 -0800 Subject: [PATCH] tty/n_hdlc: fix __might_sleep warning Fix __might_sleep warning[1] in tty/n_hdlc.c read due to copy_to_user call while current is TASK_INTERRUPTIBLE. This is a false positive since the code path does not depend on current state remaining TASK_INTERRUPTIBLE. The loop breaks out and sets TASK_RUNNING after calling copy_to_user. This patch supresses the warning by setting TASK_RUNNING before calling copy_to_user. [1] https://syzkaller.appspot.com/bug?id=17d5de7f1fcab794cb8c40032f893f52de899324 Signed-off-by: Paul Fulghum Reported-by: syzbot Cc: Tetsuo Handa Cc: Alan Cox Cc: stable Acked-by: Arnd Bergmann Signed-off-by: Greg Kroah-Hartman --- drivers/tty/n_hdlc.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/tty/n_hdlc.c b/drivers/tty/n_hdlc.c index 4164414d4c64..8bdf42bc8fc8 100644 --- a/drivers/tty/n_hdlc.c +++ b/drivers/tty/n_hdlc.c @@ -597,6 +597,7 @@ static ssize_t n_hdlc_tty_read(struct tty_struct *tty, struct file *file, /* too large for caller's buffer */ ret = -EOVERFLOW; } else { + __set_current_state(TASK_RUNNING); if (copy_to_user(buf, rbuf->buf, rbuf->count)) ret = -EFAULT; else