pve-qemu-qoup/debian/patches/extra/0015-hw-timer-hpet-Fix-expiration-time-overflow.patch
Fiona Ebner 3c4f941ac7 add more stable fixes
The patches were selected from the recent "Patch Round-up for stable
7.2.1" [0]. Those that should be relevant for our supported use-cases
(and the upcoming nvme use-case) were picked. Most of the patches
added now have not been submitted to qemu-stable before.

The follow-up for the virtio-rng-pci migration fix will break
migration between versions with the fix and without the fix when a
virtio-pci-rng(-non)-transitional device is used. Luckily Proxmox VE
only uses the virtio-pci-rng device, and this was fixed by
0006-virtio-rng-pci-fix-migration-compat-for-vectors.patch which was
applied before any public version of Proxmox VE's QEMU 7.2 package was
released.

[0]: https://lists.nongnu.org/archive/html/qemu-stable/2023-03/msg00010.html
[1]: https://bugzilla.redhat.com/show_bug.cgi?id=2162569

Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
2023-03-13 17:36:19 +01:00

81 lines
2.9 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Akihiko Odaki <akihiko.odaki@daynix.com>
Date: Tue, 31 Jan 2023 12:00:37 +0900
Subject: [PATCH] hw/timer/hpet: Fix expiration time overflow
The expiration time provided for timer_mod() can overflow if a
ridiculously large value is set to the comparator register. The
resulting value can represent a past time after rounded, forcing the
timer to fire immediately. If the timer is configured as periodic, it
will rearm the timer again, and form an endless loop.
Check if the expiration value will overflow, and if it will, stop the
timer instead of rearming the timer with the overflowed time.
This bug was found by Alexander Bulekov when fuzzing igb, a new
network device emulation:
https://patchew.org/QEMU/20230129053316.1071513-1-alxndr@bu.edu/
The fixed test case is:
fuzz/crash_2d7036941dcda1ad4380bb8a9174ed0c949bcefd
Fixes: 16b29ae180 ("Add HPET emulation to qemu (Beth Kon)")
Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Message-Id: <20230131030037.18856-1-akihiko.odaki@daynix.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
(cherry-picked from commit 37d2bcbc2a4e9c2e9061bec72a32c7e49b9f81ec)
Signed-off-by: Fiona Ebner <f.ebner@proxmox.com>
---
hw/timer/hpet.c | 19 +++++++++++++------
1 file changed, 13 insertions(+), 6 deletions(-)
diff --git a/hw/timer/hpet.c b/hw/timer/hpet.c
index 9520471be2..5f88ffdef8 100644
--- a/hw/timer/hpet.c
+++ b/hw/timer/hpet.c
@@ -352,6 +352,16 @@ static const VMStateDescription vmstate_hpet = {
}
};
+static void hpet_arm(HPETTimer *t, uint64_t ticks)
+{
+ if (ticks < ns_to_ticks(INT64_MAX / 2)) {
+ timer_mod(t->qemu_timer,
+ qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + ticks_to_ns(ticks));
+ } else {
+ timer_del(t->qemu_timer);
+ }
+}
+
/*
* timer expiration callback
*/
@@ -374,13 +384,11 @@ static void hpet_timer(void *opaque)
}
}
diff = hpet_calculate_diff(t, cur_tick);
- timer_mod(t->qemu_timer,
- qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + (int64_t)ticks_to_ns(diff));
+ hpet_arm(t, diff);
} else if (t->config & HPET_TN_32BIT && !timer_is_periodic(t)) {
if (t->wrap_flag) {
diff = hpet_calculate_diff(t, cur_tick);
- timer_mod(t->qemu_timer, qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) +
- (int64_t)ticks_to_ns(diff));
+ hpet_arm(t, diff);
t->wrap_flag = 0;
}
}
@@ -407,8 +415,7 @@ static void hpet_set_timer(HPETTimer *t)
t->wrap_flag = 1;
}
}
- timer_mod(t->qemu_timer,
- qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + (int64_t)ticks_to_ns(diff));
+ hpet_arm(t, diff);
}
static void hpet_del_timer(HPETTimer *t)