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Blame 0008-hpet-fix-buffer-overrun-on-invalid-state-load.patch

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From 5e0e0a12887c9e70356c23d20b08b08eabd4a6df Mon Sep 17 00:00:00 2001
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From: "Michael S. Tsirkin" <mst@redhat.com>
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Date: Thu, 3 Apr 2014 19:51:23 +0300
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Subject: [PATCH] hpet: fix buffer overrun on invalid state load
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CVE-2013-4527 hw/timer/hpet.c buffer overrun
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hpet is a VARRAY with a uint8 size but static array of 32
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To fix, make sure num_timers is valid using VMSTATE_VALID hook.
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Reported-by: Anthony Liguori <anthony@codemonkey.ws>
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Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
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Signed-off-by: Juan Quintela <quintela@redhat.com>
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(cherry picked from commit 3f1c49e2136fa08ab1ef3183fd55def308829584)
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---
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 hw/timer/hpet.c | 13 +++++++++++++
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 1 file changed, 13 insertions(+)
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diff --git a/hw/timer/hpet.c b/hw/timer/hpet.c
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index e15d6bc..2792f89 100644
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--- a/hw/timer/hpet.c
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+++ b/hw/timer/hpet.c
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@@ -239,6 +239,18 @@ static int hpet_pre_load(void *opaque)
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     return 0;
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 }
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+static bool hpet_validate_num_timers(void *opaque, int version_id)
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+{
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+    HPETState *s = opaque;
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+
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+    if (s->num_timers < HPET_MIN_TIMERS) {
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+        return false;
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+    } else if (s->num_timers > HPET_MAX_TIMERS) {
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+        return false;
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+    }
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+    return true;
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+}
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+
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 static int hpet_post_load(void *opaque, int version_id)
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 {
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     HPETState *s = opaque;
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@@ -307,6 +319,7 @@ static const VMStateDescription vmstate_hpet = {
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         VMSTATE_UINT64(isr, HPETState),
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         VMSTATE_UINT64(hpet_counter, HPETState),
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         VMSTATE_UINT8_V(num_timers, HPETState, 2),
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+        VMSTATE_VALIDATE("num_timers in range", hpet_validate_num_timers),
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         VMSTATE_STRUCT_VARRAY_UINT8(timer, HPETState, num_timers, 0,
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                                     vmstate_hpet_timer, HPETTimer),
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         VMSTATE_END_OF_LIST()