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| author | Paul Fulghum <paulkf@microgate.com> | 2019-01-01 12:28:53 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-01-31 08:13:44 +0100 |
| commit | d9231608a7da07f115c55a3d05eca60bcf45f52b (patch) | |
| tree | 944b914802bfbb712eff8616dde6f9295488b901 | |
| parent | be9497af163acd7587920417dfb35ec7e9acda3a (diff) | |
| download | linux-stable-d9231608a7da07f115c55a3d05eca60bcf45f52b.tar.gz linux-stable-d9231608a7da07f115c55a3d05eca60bcf45f52b.tar.bz2 linux-stable-d9231608a7da07f115c55a3d05eca60bcf45f52b.zip | |
tty/n_hdlc: fix __might_sleep warning
commit fc01d8c61ce02c034e67378cd3e645734bc18c8c upstream.
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 <paulkf@microgate.com>
Reported-by: syzbot <syzbot+c244af085a0159d22879@syzkaller.appspotmail.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: stable <stable@vger.kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/tty/n_hdlc.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/tty/n_hdlc.c b/drivers/tty/n_hdlc.c index 7b2a466616d6..08bd6b965847 100644 --- a/drivers/tty/n_hdlc.c +++ b/drivers/tty/n_hdlc.c @@ -598,6 +598,7 @@ 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 |