qemu/0032-chardev-fix-pty_chr_timer.patch
Cole Robinson 2983660f65 Rebase to pending 1.6.1 stable
CVE-2013-4377: Fix crash when unplugging virtio devices (bz #1012633, bz #1012641)
Fix 'new snapshot' slowness after the first snap (bz #988436)
Fix 9pfs xattrs on kernel 3.11 (bz #1013676)
CVE-2013-4344: buffer overflow in scsi_target_emulate_report_luns (bz #1015274, bz #1007330)
2013-10-06 14:33:55 -04:00

53 lines
1.5 KiB
Diff

From 4b5b4721464495fe76fe6e2e033cbb61dce78eef Mon Sep 17 00:00:00 2001
From: Gerd Hoffmann <kraxel@redhat.com>
Date: Thu, 22 Aug 2013 11:43:58 +0200
Subject: [PATCH] chardev: fix pty_chr_timer
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 <kraxel@redhat.com>
(cherry picked from commit b0d768c35e08d2057b63e8e77e7a513c447199fa)
Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
---
qemu-char.c | 12 ++++--------
1 file changed, 4 insertions(+), 8 deletions(-)
diff --git a/qemu-char.c b/qemu-char.c
index 1be1cf6..1621fbd 100644
--- a/qemu-char.c
+++ b/qemu-char.c
@@ -1026,15 +1026,11 @@ 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;
}