From 65b9fb19d5853b28b6748963d9e0053429655921 Mon Sep 17 00:00:00 2001 From: Gerd Hoffmann Date: Wed, 18 Sep 2013 09:53:54 +0200 Subject: [PATCH 01/18] chardev: fix pty_chr_timer RH-Author: Gerd Hoffmann Message-id: <1379498034-29529-2-git-send-email-kraxel@redhat.com> Patchwork-id: 54429 O-Subject: [RHEL-7 qemu-kvm PATCH 1/1] chardev: fix pty_chr_timer Bugzilla: 994414 RH-Acked-by: Paolo Bonzini RH-Acked-by: Markus Armbruster RH-Acked-by: Miroslav Rezanina pty_chr_timer first calls pty_chr_update_read_handler(), then clears timer_tag (because it is a one-shot timer). This is the wrong order though. pty_chr_update_read_handler might re-arm time timer, and the new timer_tag gets overwitten in that case. This leads to crashes when unplugging a pty chardev: pty_chr_close thinks no timer is running -> timer isn't canceled -> pty_chr_timer gets called with stale CharDevState -> BOOM. This patch fixes the ordering. Kill the pointless goto while being at it. https://bugzilla.redhat.com/show_bug.cgi?id=994414 Cc: qemu-stable@nongnu.org Signed-off-by: Gerd Hoffmann (cherry picked from commit b0d768c35e08d2057b63e8e77e7a513c447199fa) --- qemu-char.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) Signed-off-by: Miroslav Rezanina --- qemu-char.c | 12 ++++-------- 1 files changed, 4 insertions(+), 8 deletions(-) diff --git a/qemu-char.c b/qemu-char.c index 2fb876c..660d758 100644 --- a/qemu-char.c +++ b/qemu-char.c @@ -1029,15 +1029,11 @@ static gboolean pty_chr_timer(gpointer opaque) struct CharDriverState *chr = opaque; PtyCharDriver *s = chr->opaque; - if (s->connected) { - goto out; - } - - /* Next poll ... */ - pty_chr_update_read_handler(chr); - -out: s->timer_tag = 0; + if (!s->connected) { + /* Next poll ... */ + pty_chr_update_read_handler(chr); + } return FALSE; } -- 1.7.1