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* Thu Jun 29 2023 Jon Maloy <jmaloy@redhat.com> - 6.2.0-36 

- kvm-memory-prevent-dma-reentracy-issues.patch [bz#1999236]
- kvm-async-Add-an-optional-reentrancy-guard-to-the-BH-API.patch [bz#1999236]
- kvm-checkpatch-add-qemu_bh_new-aio_bh_new-checks.patch [bz#1999236]
- kvm-hw-replace-most-qemu_bh_new-calls-with-qemu_bh_new_g.patch [bz#1999236]
- kvm-lsi53c895a-disable-reentrancy-detection-for-script-R.patch [bz#1999236]
- kvm-bcm2835_property-disable-reentrancy-detection-for-io.patch [bz#1999236]
- kvm-raven-disable-reentrancy-detection-for-iomem.patch [bz#1999236]
- kvm-apic-disable-reentrancy-detection-for-apic-msi.patch [bz#1999236]
- kvm-async-avoid-use-after-free-on-re-entrancy-guard.patch [bz#1999236]
- kvm-memory-stricter-checks-prior-to-unsetting-engaged_in.patch [bz#1999236]
- kvm-lsi53c895a-disable-reentrancy-detection-for-MMIO-reg.patch [bz#1999236]
- kvm-hw-scsi-lsi53c895a-Fix-reentrancy-issues-in-the-LSI-.patch [bz#1999236]
- kvm-target-i386-add-support-for-FLUSH_L1D-feature.patch [bz#2216203]
- kvm-target-i386-add-support-for-FB_CLEAR-feature.patch [bz#2216203]
- kvm-migration-Disable-postcopy-multifd-migration.patch [bz#2169733]
- Resolves: bz#1999236
  (CVE-2021-3750 virt:rhel/qemu-kvm: QEMU: hcd-ehci: DMA reentrancy issue leads to use-after-free [rhel-8])
- Resolves: bz#2216203
  ([qemu-kvm]VM reports vulnerabilty to mmio_stale_data on patched host with microcode)
- Resolves: bz#2169733
  (Qemu on destination host crashed if migrate with postcopy and multifd enabled)
This commit is contained in:
Jon Maloy 2023-06-29 21:05:35 +00:00
parent 7364473352
commit fc2ddd6b1c
16 changed files with 1845 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

56
kvm-apic-disable-reentrancy-detection-for-apic-msi.patch Normal file
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@ -0,0 +1,56 @@
From 47d027147694fde94dd73305ee53b6a136cbeced Mon Sep 17 00:00:00 2001
From: Jon Maloy <jmaloy@redhat.com>
Date: Tue, 9 May 2023 10:29:03 -0400
Subject: [PATCH 08/15] apic: disable reentrancy detection for apic-msi
RH-Author: Jon Maloy <jmaloy@redhat.com>
RH-MergeRequest: 277: memory: prevent dma-reentracy issues
RH-Bugzilla: 1999236
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Commit: [8/12] 25c3cf99b00cd9adc10d6e7afa9c3e3b7da08de2 (redhat/rhel/src/qemu-kvm/jons-qemu-kvm-2)
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1999236
Upstream: Merged
CVE: CVE-2021-3750
commit 50795ee051a342c681a9b45671c552fbd6274db8
Author: Alexander Bulekov <alxndr@bu.edu>
Date: Thu Apr 27 17:10:13 2023 -0400
apic: disable reentrancy detection for apic-msi
As the code is designed for re-entrant calls to apic-msi, mark apic-msi
as reentrancy-safe.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-Id: <20230427211013.2994127-9-alxndr@bu.edu>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jon Maloy <jmaloy@redhat.com>
---
hw/intc/apic.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/hw/intc/apic.c b/hw/intc/apic.c
index 3df11c34d6..a7c2b301a8 100644
--- a/hw/intc/apic.c
+++ b/hw/intc/apic.c
@@ -883,6 +883,13 @@ static void apic_realize(DeviceState *dev, Error **errp)
memory_region_init_io(&s->io_memory, OBJECT(s), &apic_io_ops, s, "apic-msi",
APIC_SPACE_SIZE);
+ /*
+ * apic-msi's apic_mem_write can call into ioapic_eoi_broadcast, which can
+ * write back to apic-msi. As such mark the apic-msi region re-entrancy
+ * safe.
+ */
+ s->io_memory.disable_reentrancy_guard = true;
+
s->timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, apic_timer, s);
local_apics[s->id] = s;
--
2.37.3

235
kvm-async-Add-an-optional-reentrancy-guard-to-the-BH-API.patch Normal file
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@ -0,0 +1,235 @@
From 8996ac4369de7e0cb6f911db6f47c3e4ae88c8aa Mon Sep 17 00:00:00 2001
From: Jon Maloy <jmaloy@redhat.com>
Date: Tue, 9 May 2023 10:29:03 -0400
Subject: [PATCH 02/15] async: Add an optional reentrancy guard to the BH API
RH-Author: Jon Maloy <jmaloy@redhat.com>
RH-MergeRequest: 277: memory: prevent dma-reentracy issues
RH-Bugzilla: 1999236
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Commit: [2/12] b03f247e242a6cdb3eebec36477234ac77dcd20c (redhat/rhel/src/qemu-kvm/jons-qemu-kvm-2)
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1999236
Upstream: Merged
CVE: CVE-2021-3750
Conflict: The file block/graph-lock.h, inluded from include/block/aio.h,
doesn't exist in this code version. The code compiles without
issues if this include is just omitted, so we do that.
commit 9c86c97f12c060bf7484dd931f38634e166a81f0
Author: Alexander Bulekov <alxndr@bu.edu>
Date: Thu Apr 27 17:10:07 2023 -0400
async: Add an optional reentrancy guard to the BH API
Devices can pass their MemoryReentrancyGuard (from their DeviceState),
when creating new BHes. Then, the async API will toggle the guard
before/after calling the BH call-back. This prevents bh->mmio reentrancy
issues.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-Id: <20230427211013.2994127-3-alxndr@bu.edu>
[thuth: Fix "line over 90 characters" checkpatch.pl error]
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jon Maloy <jmaloy@redhat.com>
---
docs/devel/multiple-iothreads.txt | 7 +++++++
include/block/aio.h | 18 ++++++++++++++++--
include/qemu/main-loop.h | 7 +++++--
tests/unit/ptimer-test-stubs.c | 3 ++-
util/async.c | 18 +++++++++++++++++-
util/main-loop.c | 6 ++++--
util/trace-events | 1 +
7 files changed, 52 insertions(+), 8 deletions(-)
diff --git a/docs/devel/multiple-iothreads.txt b/docs/devel/multiple-iothreads.txt
index aeb997bed5..a11576bc74 100644
--- a/docs/devel/multiple-iothreads.txt
+++ b/docs/devel/multiple-iothreads.txt
@@ -61,6 +61,7 @@ There are several old APIs that use the main loop AioContext:
* LEGACY qemu_aio_set_event_notifier() - monitor an event notifier
* LEGACY timer_new_ms() - create a timer
* LEGACY qemu_bh_new() - create a BH
+ * LEGACY qemu_bh_new_guarded() - create a BH with a device re-entrancy guard
* LEGACY qemu_aio_wait() - run an event loop iteration
Since they implicitly work on the main loop they cannot be used in code that
@@ -72,8 +73,14 @@ Instead, use the AioContext functions directly (see include/block/aio.h):
* aio_set_event_notifier() - monitor an event notifier
* aio_timer_new() - create a timer
* aio_bh_new() - create a BH
+ * aio_bh_new_guarded() - create a BH with a device re-entrancy guard
* aio_poll() - run an event loop iteration
+The qemu_bh_new_guarded/aio_bh_new_guarded APIs accept a "MemReentrancyGuard"
+argument, which is used to check for and prevent re-entrancy problems. For
+BHs associated with devices, the reentrancy-guard is contained in the
+corresponding DeviceState and named "mem_reentrancy_guard".
+
The AioContext can be obtained from the IOThread using
iothread_get_aio_context() or for the main loop using qemu_get_aio_context().
Code that takes an AioContext argument works both in IOThreads or the main
diff --git a/include/block/aio.h b/include/block/aio.h
index 47fbe9d81f..c7da152985 100644
--- a/include/block/aio.h
+++ b/include/block/aio.h
@@ -22,6 +22,8 @@
#include "qemu/event_notifier.h"
#include "qemu/thread.h"
#include "qemu/timer.h"
+#include "hw/qdev-core.h"
+
typedef struct BlockAIOCB BlockAIOCB;
typedef void BlockCompletionFunc(void *opaque, int ret);
@@ -321,9 +323,11 @@ void aio_bh_schedule_oneshot_full(AioContext *ctx, QEMUBHFunc *cb, void *opaque,
* is opaque and must be allocated prior to its use.
*
* @name: A human-readable identifier for debugging purposes.
+ * @reentrancy_guard: A guard set when entering a cb to prevent
+ * device-reentrancy issues
*/
QEMUBH *aio_bh_new_full(AioContext *ctx, QEMUBHFunc *cb, void *opaque,
- const char *name);
+ const char *name, MemReentrancyGuard *reentrancy_guard);
/**
* aio_bh_new: Allocate a new bottom half structure
@@ -332,7 +336,17 @@ QEMUBH *aio_bh_new_full(AioContext *ctx, QEMUBHFunc *cb, void *opaque,
* string.
*/
#define aio_bh_new(ctx, cb, opaque) \
- aio_bh_new_full((ctx), (cb), (opaque), (stringify(cb)))
+ aio_bh_new_full((ctx), (cb), (opaque), (stringify(cb)), NULL)
+
+/**
+ * aio_bh_new_guarded: Allocate a new bottom half structure with a
+ * reentrancy_guard
+ *
+ * A convenience wrapper for aio_bh_new_full() that uses the cb as the name
+ * string.
+ */
+#define aio_bh_new_guarded(ctx, cb, opaque, guard) \
+ aio_bh_new_full((ctx), (cb), (opaque), (stringify(cb)), guard)
/**
* aio_notify: Force processing of pending events.
diff --git a/include/qemu/main-loop.h b/include/qemu/main-loop.h
index 8dbc6fcb89..85dd5ada9e 100644
--- a/include/qemu/main-loop.h
+++ b/include/qemu/main-loop.h
@@ -294,9 +294,12 @@ void qemu_cond_timedwait_iothread(QemuCond *cond, int ms);
void qemu_fd_register(int fd);
+#define qemu_bh_new_guarded(cb, opaque, guard) \
+ qemu_bh_new_full((cb), (opaque), (stringify(cb)), guard)
#define qemu_bh_new(cb, opaque) \
- qemu_bh_new_full((cb), (opaque), (stringify(cb)))
-QEMUBH *qemu_bh_new_full(QEMUBHFunc *cb, void *opaque, const char *name);
+ qemu_bh_new_full((cb), (opaque), (stringify(cb)), NULL)
+QEMUBH *qemu_bh_new_full(QEMUBHFunc *cb, void *opaque, const char *name,
+ MemReentrancyGuard *reentrancy_guard);
void qemu_bh_schedule_idle(QEMUBH *bh);
enum {
diff --git a/tests/unit/ptimer-test-stubs.c b/tests/unit/ptimer-test-stubs.c
index 2a3ef58799..a7a2d08e7e 100644
--- a/tests/unit/ptimer-test-stubs.c
+++ b/tests/unit/ptimer-test-stubs.c
@@ -108,7 +108,8 @@ int64_t qemu_clock_deadline_ns_all(QEMUClockType type, int attr_mask)
return deadline;
}
-QEMUBH *qemu_bh_new_full(QEMUBHFunc *cb, void *opaque, const char *name)
+QEMUBH *qemu_bh_new_full(QEMUBHFunc *cb, void *opaque, const char *name,
+ MemReentrancyGuard *reentrancy_guard)
{
QEMUBH *bh = g_new(QEMUBH, 1);
diff --git a/util/async.c b/util/async.c
index 2a63bf90f2..1fff02e7fc 100644
--- a/util/async.c
+++ b/util/async.c
@@ -62,6 +62,7 @@ struct QEMUBH {
void *opaque;
QSLIST_ENTRY(QEMUBH) next;
unsigned flags;
+ MemReentrancyGuard *reentrancy_guard;
};
/* Called concurrently from any thread */
@@ -127,7 +128,7 @@ void aio_bh_schedule_oneshot_full(AioContext *ctx, QEMUBHFunc *cb,
}
QEMUBH *aio_bh_new_full(AioContext *ctx, QEMUBHFunc *cb, void *opaque,
- const char *name)
+ const char *name, MemReentrancyGuard *reentrancy_guard)
{
QEMUBH *bh;
bh = g_new(QEMUBH, 1);
@@ -136,13 +137,28 @@ QEMUBH *aio_bh_new_full(AioContext *ctx, QEMUBHFunc *cb, void *opaque,
.cb = cb,
.opaque = opaque,
.name = name,
+ .reentrancy_guard = reentrancy_guard,
};
return bh;
}
void aio_bh_call(QEMUBH *bh)
{
+ bool last_engaged_in_io = false;
+
+ if (bh->reentrancy_guard) {
+ last_engaged_in_io = bh->reentrancy_guard->engaged_in_io;
+ if (bh->reentrancy_guard->engaged_in_io) {
+ trace_reentrant_aio(bh->ctx, bh->name);
+ }
+ bh->reentrancy_guard->engaged_in_io = true;
+ }
+
bh->cb(bh->opaque);
+
+ if (bh->reentrancy_guard) {
+ bh->reentrancy_guard->engaged_in_io = last_engaged_in_io;
+ }
}
/* Multiple occurrences of aio_bh_poll cannot be called concurrently. */
diff --git a/util/main-loop.c b/util/main-loop.c
index 06b18b195c..1eacf04691 100644
--- a/util/main-loop.c
+++ b/util/main-loop.c
@@ -544,9 +544,11 @@ void main_loop_wait(int nonblocking)
/* Functions to operate on the main QEMU AioContext. */
-QEMUBH *qemu_bh_new_full(QEMUBHFunc *cb, void *opaque, const char *name)
+QEMUBH *qemu_bh_new_full(QEMUBHFunc *cb, void *opaque, const char *name,
+ MemReentrancyGuard *reentrancy_guard)
{
- return aio_bh_new_full(qemu_aio_context, cb, opaque, name);
+ return aio_bh_new_full(qemu_aio_context, cb, opaque, name,
+ reentrancy_guard);
}
/*
diff --git a/util/trace-events b/util/trace-events
index c8f53d7d9f..dc3b1eb3bf 100644
--- a/util/trace-events
+++ b/util/trace-events
@@ -11,6 +11,7 @@ poll_remove(void *ctx, void *node, int fd) "ctx %p node %p fd %d"
# async.c
aio_co_schedule(void *ctx, void *co) "ctx %p co %p"
aio_co_schedule_bh_cb(void *ctx, void *co) "ctx %p co %p"
+reentrant_aio(void *ctx, const char *name) "ctx %p name %s"
# thread-pool.c
thread_pool_submit(void *pool, void *req, void *opaque) "pool %p req %p opaque %p"
--
2.37.3

71
kvm-async-avoid-use-after-free-on-re-entrancy-guard.patch Normal file
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@ -0,0 +1,71 @@
From d754050d260e2ad890cecd975df6e163c531b40e Mon Sep 17 00:00:00 2001
From: Jon Maloy <jmaloy@redhat.com>
Date: Tue, 9 May 2023 10:29:03 -0400
Subject: [PATCH 09/15] async: avoid use-after-free on re-entrancy guard
RH-Author: Jon Maloy <jmaloy@redhat.com>
RH-MergeRequest: 277: memory: prevent dma-reentracy issues
RH-Bugzilla: 1999236
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Commit: [9/12] d357650e581c3921bbfe3e2fde5e3f55853b5fab (redhat/rhel/src/qemu-kvm/jons-qemu-kvm-2)
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1999236
Upstream: Merged
CVE: CVE-2021-3750
commit 7915bd06f25e1803778081161bf6fa10c42dc7cd
Author: Alexander Bulekov <alxndr@bu.edu>
Date: Mon May 1 10:19:56 2023 -0400
async: avoid use-after-free on re-entrancy guard
A BH callback can free the BH, causing a use-after-free in aio_bh_call.
Fix that by keeping a local copy of the re-entrancy guard pointer.
Buglink: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=58513
Fixes: 9c86c97f12 ("async: Add an optional reentrancy guard to the BH API")
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Message-Id: <20230501141956.3444868-1-alxndr@bu.edu>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jon Maloy <jmaloy@redhat.com>
---
util/async.c | 14 ++++++++------
1 file changed, 8 insertions(+), 6 deletions(-)
diff --git a/util/async.c b/util/async.c
index 1fff02e7fc..ffe0541c3b 100644
--- a/util/async.c
+++ b/util/async.c
@@ -146,18 +146,20 @@ void aio_bh_call(QEMUBH *bh)
{
bool last_engaged_in_io = false;
- if (bh->reentrancy_guard) {
- last_engaged_in_io = bh->reentrancy_guard->engaged_in_io;
- if (bh->reentrancy_guard->engaged_in_io) {
+ /* Make a copy of the guard-pointer as cb may free the bh */
+ MemReentrancyGuard *reentrancy_guard = bh->reentrancy_guard;
+ if (reentrancy_guard) {
+ last_engaged_in_io = reentrancy_guard->engaged_in_io;
+ if (reentrancy_guard->engaged_in_io) {
trace_reentrant_aio(bh->ctx, bh->name);
}
- bh->reentrancy_guard->engaged_in_io = true;
+ reentrancy_guard->engaged_in_io = true;
}
bh->cb(bh->opaque);
- if (bh->reentrancy_guard) {
- bh->reentrancy_guard->engaged_in_io = last_engaged_in_io;
+ if (reentrancy_guard) {
+ reentrancy_guard->engaged_in_io = last_engaged_in_io;
}
}
--
2.37.3

58
kvm-bcm2835_property-disable-reentrancy-detection-for-io.patch Normal file
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@ -0,0 +1,58 @@
From 7715635d018351e0a5c4c25aec2c71a2fe3b9e69 Mon Sep 17 00:00:00 2001
From: Jon Maloy <jmaloy@redhat.com>
Date: Tue, 9 May 2023 10:29:03 -0400
Subject: [PATCH 06/15] bcm2835_property: disable reentrancy detection for
iomem
RH-Author: Jon Maloy <jmaloy@redhat.com>
RH-MergeRequest: 277: memory: prevent dma-reentracy issues
RH-Bugzilla: 1999236
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Commit: [6/12] 4d6187430ca1c4309a36824c0c6815d2a763db1a (redhat/rhel/src/qemu-kvm/jons-qemu-kvm-2)
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1999236
Upstream: Merged
CVE: CVE-2021-3750
commit 985c4a4e547afb9573b6bd6843d20eb2c3d1d1cd
Author: Alexander Bulekov <alxndr@bu.edu>
Date: Thu Apr 27 17:10:11 2023 -0400
bcm2835_property: disable reentrancy detection for iomem
As the code is designed for re-entrant calls from bcm2835_property to
bcm2835_mbox and back into bcm2835_property, mark iomem as
reentrancy-safe.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20230427211013.2994127-7-alxndr@bu.edu>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jon Maloy <jmaloy@redhat.com>
---
hw/misc/bcm2835_property.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/hw/misc/bcm2835_property.c b/hw/misc/bcm2835_property.c
index 73941bdae9..022b5a849c 100644
--- a/hw/misc/bcm2835_property.c
+++ b/hw/misc/bcm2835_property.c
@@ -377,6 +377,13 @@ static void bcm2835_property_init(Object *obj)
memory_region_init_io(&s->iomem, OBJECT(s), &bcm2835_property_ops, s,
TYPE_BCM2835_PROPERTY, 0x10);
+
+ /*
+ * bcm2835_property_ops call into bcm2835_mbox, which in-turn reads from
+ * iomem. As such, mark iomem as re-entracy safe.
+ */
+ s->iomem.disable_reentrancy_guard = true;
+
sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem);
sysbus_init_irq(SYS_BUS_DEVICE(s), &s->mbox_irq);
}
--
2.37.3

56
kvm-checkpatch-add-qemu_bh_new-aio_bh_new-checks.patch Normal file
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@ -0,0 +1,56 @@
From 866a3b56f6a2d43f3cf7b3313fb41808bc5e6e1f Mon Sep 17 00:00:00 2001
From: Jon Maloy <jmaloy@redhat.com>
Date: Tue, 9 May 2023 10:29:03 -0400
Subject: [PATCH 03/15] checkpatch: add qemu_bh_new/aio_bh_new checks
RH-Author: Jon Maloy <jmaloy@redhat.com>
RH-MergeRequest: 277: memory: prevent dma-reentracy issues
RH-Bugzilla: 1999236
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Commit: [3/12] 620b480b0878c18223f3cc103450bc16aa6d7e21 (redhat/rhel/src/qemu-kvm/jons-qemu-kvm-2)
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1999236
Upstream: Merged
CVE: CVE-2021-3750
commit ef56ffbdd6b0605dc1e305611287b948c970e236
Author: Alexander Bulekov <alxndr@bu.edu>
Date: Thu Apr 27 17:10:08 2023 -0400
checkpatch: add qemu_bh_new/aio_bh_new checks
Advise authors to use the _guarded versions of the APIs, instead.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-Id: <20230427211013.2994127-4-alxndr@bu.edu>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jon Maloy <jmaloy@redhat.com>
---
scripts/checkpatch.pl | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index cb8eff233e..b2428e80cc 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -2858,6 +2858,14 @@ sub process {
if ($line =~ /\bsignal\s*\(/ && !($line =~ /SIG_(?:IGN|DFL)/)) {
ERROR("use sigaction to establish signal handlers; signal is not portable\n" . $herecurr);
}
+# recommend qemu_bh_new_guarded instead of qemu_bh_new
+ if ($realfile =~ /.*\/hw\/.*/ && $line =~ /\bqemu_bh_new\s*\(/) {
+ ERROR("use qemu_bh_new_guarded() instead of qemu_bh_new() to avoid reentrancy problems\n" . $herecurr);
+ }
+# recommend aio_bh_new_guarded instead of aio_bh_new
+ if ($realfile =~ /.*\/hw\/.*/ && $line =~ /\baio_bh_new\s*\(/) {
+ ERROR("use aio_bh_new_guarded() instead of aio_bh_new() to avoid reentrancy problems\n" . $herecurr);
+ }
# check for module_init(), use category-specific init macros explicitly please
if ($line =~ /^module_init\s*\(/) {
ERROR("please use block_init(), type_init() etc. instead of module_init()\n" . $herecurr);
--
2.37.3

449
kvm-hw-replace-most-qemu_bh_new-calls-with-qemu_bh_new_g.patch Normal file
View File

@ -0,0 +1,449 @@
From 146cfb23b76b898f08690ffc14aab16d22a41404 Mon Sep 17 00:00:00 2001
From: Jon Maloy <jmaloy@redhat.com>
Date: Tue, 9 May 2023 10:29:03 -0400
Subject: [PATCH 04/15] hw: replace most qemu_bh_new calls with
qemu_bh_new_guarded
RH-Author: Jon Maloy <jmaloy@redhat.com>
RH-MergeRequest: 277: memory: prevent dma-reentracy issues
RH-Bugzilla: 1999236
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Commit: [4/12] 00c51d30246b3aa529f6043e35ee471660aa1fce (redhat/rhel/src/qemu-kvm/jons-qemu-kvm-2)
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1999236
Upstream: Merged
CVE: CVE-2021-3750
Conflicts: In hw/nvme/ctrl.c there are no calls to qemu_bh_new() at the two locations
the replacement is done in the upstream commit. Instead, timer_new_ns() is
used. We leave these functions unaltered.
commit f63192b0544af5d3e4d5edfd85ab520fcf671377
Author: Alexander Bulekov <alxndr@bu.edu>
Date: Thu Apr 27 17:10:09 2023 -0400
hw: replace most qemu_bh_new calls with qemu_bh_new_guarded
This protects devices from bh->mmio reentrancy issues.
Thanks: Thomas Huth <thuth@redhat.com> for diagnosing OS X test failure.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Paul Durrant <paul@xen.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20230427211013.2994127-5-alxndr@bu.edu>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jon Maloy <jmaloy@redhat.com>
---
hw/9pfs/xen-9p-backend.c | 5 ++++-
hw/block/dataplane/virtio-blk.c | 3 ++-
hw/block/dataplane/xen-block.c | 5 +++--
hw/char/virtio-serial-bus.c | 3 ++-
hw/display/qxl.c | 9 ++++++---
hw/display/virtio-gpu.c | 6 ++++--
hw/ide/ahci.c | 3 ++-
hw/ide/ahci_internal.h | 1 +
hw/ide/core.c | 4 +++-
hw/misc/imx_rngc.c | 6 ++++--
hw/misc/macio/mac_dbdma.c | 2 +-
hw/net/virtio-net.c | 3 ++-
hw/scsi/mptsas.c | 3 ++-
hw/scsi/scsi-bus.c | 3 ++-
hw/scsi/vmw_pvscsi.c | 3 ++-
hw/usb/dev-uas.c | 3 ++-
hw/usb/hcd-dwc2.c | 3 ++-
hw/usb/hcd-ehci.c | 3 ++-
hw/usb/hcd-uhci.c | 2 +-
hw/usb/host-libusb.c | 6 ++++--
hw/usb/redirect.c | 6 ++++--
hw/usb/xen-usb.c | 3 ++-
hw/virtio/virtio-balloon.c | 5 +++--
hw/virtio/virtio-crypto.c | 3 ++-
24 files changed, 62 insertions(+), 31 deletions(-)
diff --git a/hw/9pfs/xen-9p-backend.c b/hw/9pfs/xen-9p-backend.c
index 65c4979c3c..09f7c13588 100644
--- a/hw/9pfs/xen-9p-backend.c
+++ b/hw/9pfs/xen-9p-backend.c
@@ -60,6 +60,7 @@ typedef struct Xen9pfsDev {
int num_rings;
Xen9pfsRing *rings;
+ MemReentrancyGuard mem_reentrancy_guard;
} Xen9pfsDev;
static void xen_9pfs_disconnect(struct XenLegacyDevice *xendev);
@@ -441,7 +442,9 @@ static int xen_9pfs_connect(struct XenLegacyDevice *xendev)
xen_9pdev->rings[i].ring.out = xen_9pdev->rings[i].data +
XEN_FLEX_RING_SIZE(ring_order);
- xen_9pdev->rings[i].bh = qemu_bh_new(xen_9pfs_bh, &xen_9pdev->rings[i]);
+ xen_9pdev->rings[i].bh = qemu_bh_new_guarded(xen_9pfs_bh,
+ &xen_9pdev->rings[i],
+ &xen_9pdev->mem_reentrancy_guard);
xen_9pdev->rings[i].out_cons = 0;
xen_9pdev->rings[i].out_size = 0;
xen_9pdev->rings[i].inprogress = false;
diff --git a/hw/block/dataplane/virtio-blk.c b/hw/block/dataplane/virtio-blk.c
index ee5a5352dc..5f0de7da1e 100644
--- a/hw/block/dataplane/virtio-blk.c
+++ b/hw/block/dataplane/virtio-blk.c
@@ -127,7 +127,8 @@ bool virtio_blk_data_plane_create(VirtIODevice *vdev, VirtIOBlkConf *conf,
} else {
s->ctx = qemu_get_aio_context();
}
- s->bh = aio_bh_new(s->ctx, notify_guest_bh, s);
+ s->bh = aio_bh_new_guarded(s->ctx, notify_guest_bh, s,
+ &DEVICE(vdev)->mem_reentrancy_guard);
s->batch_notify_vqs = bitmap_new(conf->num_queues);
*dataplane = s;
diff --git a/hw/block/dataplane/xen-block.c b/hw/block/dataplane/xen-block.c
index 860787580a..07855feea6 100644
--- a/hw/block/dataplane/xen-block.c
+++ b/hw/block/dataplane/xen-block.c
@@ -631,8 +631,9 @@ XenBlockDataPlane *xen_block_dataplane_create(XenDevice *xendev,
} else {
dataplane->ctx = qemu_get_aio_context();
}
- dataplane->bh = aio_bh_new(dataplane->ctx, xen_block_dataplane_bh,
- dataplane);
+ dataplane->bh = aio_bh_new_guarded(dataplane->ctx, xen_block_dataplane_bh,
+ dataplane,
+ &DEVICE(xendev)->mem_reentrancy_guard);
return dataplane;
}
diff --git a/hw/char/virtio-serial-bus.c b/hw/char/virtio-serial-bus.c
index f01ec2137c..f18124b155 100644
--- a/hw/char/virtio-serial-bus.c
+++ b/hw/char/virtio-serial-bus.c
@@ -985,7 +985,8 @@ static void virtser_port_device_realize(DeviceState *dev, Error **errp)
return;
}
- port->bh = qemu_bh_new(flush_queued_data_bh, port);
+ port->bh = qemu_bh_new_guarded(flush_queued_data_bh, port,
+ &dev->mem_reentrancy_guard);
port->elem = NULL;
}
diff --git a/hw/display/qxl.c b/hw/display/qxl.c
index bcd9e8716a..0f663b9912 100644
--- a/hw/display/qxl.c
+++ b/hw/display/qxl.c
@@ -2206,11 +2206,14 @@ static void qxl_realize_common(PCIQXLDevice *qxl, Error **errp)
qemu_add_vm_change_state_handler(qxl_vm_change_state_handler, qxl);
- qxl->update_irq = qemu_bh_new(qxl_update_irq_bh, qxl);
+ qxl->update_irq = qemu_bh_new_guarded(qxl_update_irq_bh, qxl,
+ &DEVICE(qxl)->mem_reentrancy_guard);
qxl_reset_state(qxl);
- qxl->update_area_bh = qemu_bh_new(qxl_render_update_area_bh, qxl);
- qxl->ssd.cursor_bh = qemu_bh_new(qemu_spice_cursor_refresh_bh, &qxl->ssd);
+ qxl->update_area_bh = qemu_bh_new_guarded(qxl_render_update_area_bh, qxl,
+ &DEVICE(qxl)->mem_reentrancy_guard);
+ qxl->ssd.cursor_bh = qemu_bh_new_guarded(qemu_spice_cursor_refresh_bh, &qxl->ssd,
+ &DEVICE(qxl)->mem_reentrancy_guard);
}
static void qxl_realize_primary(PCIDevice *dev, Error **errp)
diff --git a/hw/display/virtio-gpu.c b/hw/display/virtio-gpu.c
index d78b9700c7..ecf9079145 100644
--- a/hw/display/virtio-gpu.c
+++ b/hw/display/virtio-gpu.c
@@ -1332,8 +1332,10 @@ void virtio_gpu_device_realize(DeviceState *qdev, Error **errp)
g->ctrl_vq = virtio_get_queue(vdev, 0);
g->cursor_vq = virtio_get_queue(vdev, 1);
- g->ctrl_bh = qemu_bh_new(virtio_gpu_ctrl_bh, g);
- g->cursor_bh = qemu_bh_new(virtio_gpu_cursor_bh, g);
+ g->ctrl_bh = qemu_bh_new_guarded(virtio_gpu_ctrl_bh, g,
+ &qdev->mem_reentrancy_guard);
+ g->cursor_bh = qemu_bh_new_guarded(virtio_gpu_cursor_bh, g,
+ &qdev->mem_reentrancy_guard);
QTAILQ_INIT(&g->reslist);
QTAILQ_INIT(&g->cmdq);
QTAILQ_INIT(&g->fenceq);
diff --git a/hw/ide/ahci.c b/hw/ide/ahci.c
index a94c6e26fb..7488b28065 100644
--- a/hw/ide/ahci.c
+++ b/hw/ide/ahci.c
@@ -1504,7 +1504,8 @@ static void ahci_cmd_done(const IDEDMA *dma)
ahci_write_fis_d2h(ad);
if (ad->port_regs.cmd_issue && !ad->check_bh) {
- ad->check_bh = qemu_bh_new(ahci_check_cmd_bh, ad);
+ ad->check_bh = qemu_bh_new_guarded(ahci_check_cmd_bh, ad,
+ &ad->mem_reentrancy_guard);
qemu_bh_schedule(ad->check_bh);
}
}
diff --git a/hw/ide/ahci_internal.h b/hw/ide/ahci_internal.h
index 109de9e2d1..a7768dd69e 100644
--- a/hw/ide/ahci_internal.h
+++ b/hw/ide/ahci_internal.h
@@ -321,6 +321,7 @@ struct AHCIDevice {
bool init_d2h_sent;
AHCICmdHdr *cur_cmd;
NCQTransferState ncq_tfs[AHCI_MAX_CMDS];
+ MemReentrancyGuard mem_reentrancy_guard;
};
struct AHCIPCIState {
diff --git a/hw/ide/core.c b/hw/ide/core.c
index 15138225be..05a32d0a99 100644
--- a/hw/ide/core.c
+++ b/hw/ide/core.c
@@ -510,6 +510,7 @@ BlockAIOCB *ide_issue_trim(
BlockCompletionFunc *cb, void *cb_opaque, void *opaque)
{
IDEState *s = opaque;
+ IDEDevice *dev = s->unit ? s->bus->slave : s->bus->master;
TrimAIOCB *iocb;
/* Paired with a decrement in ide_trim_bh_cb() */
@@ -517,7 +518,8 @@ BlockAIOCB *ide_issue_trim(
iocb = blk_aio_get(&trim_aiocb_info, s->blk, cb, cb_opaque);
iocb->s = s;
- iocb->bh = qemu_bh_new(ide_trim_bh_cb, iocb);
+ iocb->bh = qemu_bh_new_guarded(ide_trim_bh_cb, iocb,
+ &DEVICE(dev)->mem_reentrancy_guard);
iocb->ret = 0;
iocb->qiov = qiov;
iocb->i = -1;
diff --git a/hw/misc/imx_rngc.c b/hw/misc/imx_rngc.c
index 632c03779c..082c6980ad 100644
--- a/hw/misc/imx_rngc.c
+++ b/hw/misc/imx_rngc.c
@@ -228,8 +228,10 @@ static void imx_rngc_realize(DeviceState *dev, Error **errp)
sysbus_init_mmio(sbd, &s->iomem);
sysbus_init_irq(sbd, &s->irq);
- s->self_test_bh = qemu_bh_new(imx_rngc_self_test, s);
- s->seed_bh = qemu_bh_new(imx_rngc_seed, s);
+ s->self_test_bh = qemu_bh_new_guarded(imx_rngc_self_test, s,
+ &dev->mem_reentrancy_guard);
+ s->seed_bh = qemu_bh_new_guarded(imx_rngc_seed, s,
+ &dev->mem_reentrancy_guard);
}
static void imx_rngc_reset(DeviceState *dev)
diff --git a/hw/misc/macio/mac_dbdma.c b/hw/misc/macio/mac_dbdma.c
index e220f1a927..f6a9e76fe7 100644
--- a/hw/misc/macio/mac_dbdma.c
+++ b/hw/misc/macio/mac_dbdma.c
@@ -912,7 +912,7 @@ static void mac_dbdma_realize(DeviceState *dev, Error **errp)
{
DBDMAState *s = MAC_DBDMA(dev);
- s->bh = qemu_bh_new(DBDMA_run_bh, s);
+ s->bh = qemu_bh_new_guarded(DBDMA_run_bh, s, &dev->mem_reentrancy_guard);
}
static void mac_dbdma_class_init(ObjectClass *oc, void *data)
diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index 7e172ef829..ddaa8fa122 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -2753,7 +2753,8 @@ static void virtio_net_add_queue(VirtIONet *n, int index)
n->vqs[index].tx_vq =
virtio_add_queue(vdev, n->net_conf.tx_queue_size,
virtio_net_handle_tx_bh);
- n->vqs[index].tx_bh = qemu_bh_new(virtio_net_tx_bh, &n->vqs[index]);
+ n->vqs[index].tx_bh = qemu_bh_new_guarded(virtio_net_tx_bh, &n->vqs[index],
+ &DEVICE(vdev)->mem_reentrancy_guard);
}
n->vqs[index].tx_waiting = 0;
diff --git a/hw/scsi/mptsas.c b/hw/scsi/mptsas.c
index f6c7765544..ab8aaca85d 100644
--- a/hw/scsi/mptsas.c
+++ b/hw/scsi/mptsas.c
@@ -1313,7 +1313,8 @@ static void mptsas_scsi_realize(PCIDevice *dev, Error **errp)
}
s->max_devices = MPTSAS_NUM_PORTS;
- s->request_bh = qemu_bh_new(mptsas_fetch_requests, s);
+ s->request_bh = qemu_bh_new_guarded(mptsas_fetch_requests, s,
+ &DEVICE(dev)->mem_reentrancy_guard);
scsi_bus_init(&s->bus, sizeof(s->bus), &dev->qdev, &mptsas_scsi_info);
}
diff --git a/hw/scsi/scsi-bus.c b/hw/scsi/scsi-bus.c
index 77325d8cc7..b506ab7d04 100644
--- a/hw/scsi/scsi-bus.c
+++ b/hw/scsi/scsi-bus.c
@@ -192,7 +192,8 @@ static void scsi_dma_restart_cb(void *opaque, bool running, RunState state)
AioContext *ctx = blk_get_aio_context(s->conf.blk);
/* The reference is dropped in scsi_dma_restart_bh.*/
object_ref(OBJECT(s));
- s->bh = aio_bh_new(ctx, scsi_dma_restart_bh, s);
+ s->bh = aio_bh_new_guarded(ctx, scsi_dma_restart_bh, s,
+ &DEVICE(s)->mem_reentrancy_guard);
qemu_bh_schedule(s->bh);
}
}
diff --git a/hw/scsi/vmw_pvscsi.c b/hw/scsi/vmw_pvscsi.c
index cd76bd67ab..4c36febbc0 100644
--- a/hw/scsi/vmw_pvscsi.c
+++ b/hw/scsi/vmw_pvscsi.c
@@ -1178,7 +1178,8 @@ pvscsi_realizefn(PCIDevice *pci_dev, Error **errp)
pcie_endpoint_cap_init(pci_dev, PVSCSI_EXP_EP_OFFSET);
}
- s->completion_worker = qemu_bh_new(pvscsi_process_completion_queue, s);
+ s->completion_worker = qemu_bh_new_guarded(pvscsi_process_completion_queue, s,
+ &DEVICE(pci_dev)->mem_reentrancy_guard);
scsi_bus_init(&s->bus, sizeof(s->bus), DEVICE(pci_dev), &pvscsi_scsi_info);
/* override default SCSI bus hotplug-handler, with pvscsi's one */
diff --git a/hw/usb/dev-uas.c b/hw/usb/dev-uas.c
index 599d6b52a0..a36a7c3013 100644
--- a/hw/usb/dev-uas.c
+++ b/hw/usb/dev-uas.c
@@ -935,7 +935,8 @@ static void usb_uas_realize(USBDevice *dev, Error **errp)
QTAILQ_INIT(&uas->results);
QTAILQ_INIT(&uas->requests);
- uas->status_bh = qemu_bh_new(usb_uas_send_status_bh, uas);
+ uas->status_bh = qemu_bh_new_guarded(usb_uas_send_status_bh, uas,
+ &d->mem_reentrancy_guard);
dev->flags |= (1 << USB_DEV_FLAG_IS_SCSI_STORAGE);
scsi_bus_init(&uas->bus, sizeof(uas->bus), DEVICE(dev), &usb_uas_scsi_info);
diff --git a/hw/usb/hcd-dwc2.c b/hw/usb/hcd-dwc2.c
index e1d96acf7e..0e238f8422 100644
--- a/hw/usb/hcd-dwc2.c
+++ b/hw/usb/hcd-dwc2.c
@@ -1364,7 +1364,8 @@ static void dwc2_realize(DeviceState *dev, Error **errp)
s->fi = USB_FRMINTVL - 1;
s->eof_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, dwc2_frame_boundary, s);
s->frame_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, dwc2_work_timer, s);
- s->async_bh = qemu_bh_new(dwc2_work_bh, s);
+ s->async_bh = qemu_bh_new_guarded(dwc2_work_bh, s,
+ &dev->mem_reentrancy_guard);
sysbus_init_irq(sbd, &s->irq);
}
diff --git a/hw/usb/hcd-ehci.c b/hw/usb/hcd-ehci.c
index 6caa7ac6c2..df4ff6f2c1 100644
--- a/hw/usb/hcd-ehci.c
+++ b/hw/usb/hcd-ehci.c
@@ -2528,7 +2528,8 @@ void usb_ehci_realize(EHCIState *s, DeviceState *dev, Error **errp)
}
s->frame_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, ehci_work_timer, s);
- s->async_bh = qemu_bh_new(ehci_work_bh, s);
+ s->async_bh = qemu_bh_new_guarded(ehci_work_bh, s,
+ &dev->mem_reentrancy_guard);
s->device = dev;
s->vmstate = qemu_add_vm_change_state_handler(usb_ehci_vm_state_change, s);
diff --git a/hw/usb/hcd-uhci.c b/hw/usb/hcd-uhci.c
index 7930b868fa..469c5e57e9 100644
--- a/hw/usb/hcd-uhci.c
+++ b/hw/usb/hcd-uhci.c
@@ -1195,7 +1195,7 @@ void usb_uhci_common_realize(PCIDevice *dev, Error **errp)
USB_SPEED_MASK_LOW | USB_SPEED_MASK_FULL);
}
}
- s->bh = qemu_bh_new(uhci_bh, s);
+ s->bh = qemu_bh_new_guarded(uhci_bh, s, &DEVICE(dev)->mem_reentrancy_guard);
s->frame_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, uhci_frame_timer, s);
s->num_ports_vmstate = NB_PORTS;
QTAILQ_INIT(&s->queues);
diff --git a/hw/usb/host-libusb.c b/hw/usb/host-libusb.c
index d0d46dd0a4..09b961116b 100644
--- a/hw/usb/host-libusb.c
+++ b/hw/usb/host-libusb.c
@@ -1141,7 +1141,8 @@ static void usb_host_nodev_bh(void *opaque)
static void usb_host_nodev(USBHostDevice *s)
{
if (!s->bh_nodev) {
- s->bh_nodev = qemu_bh_new(usb_host_nodev_bh, s);
+ s->bh_nodev = qemu_bh_new_guarded(usb_host_nodev_bh, s,
+ &DEVICE(s)->mem_reentrancy_guard);
}
qemu_bh_schedule(s->bh_nodev);
}
@@ -1739,7 +1740,8 @@ static int usb_host_post_load(void *opaque, int version_id)
USBHostDevice *dev = opaque;
if (!dev->bh_postld) {
- dev->bh_postld = qemu_bh_new(usb_host_post_load_bh, dev);
+ dev->bh_postld = qemu_bh_new_guarded(usb_host_post_load_bh, dev,
+ &DEVICE(dev)->mem_reentrancy_guard);
}
qemu_bh_schedule(dev->bh_postld);
dev->bh_postld_pending = true;
diff --git a/hw/usb/redirect.c b/hw/usb/redirect.c
index 5f0ef9cb3b..59cd3cd7c4 100644
--- a/hw/usb/redirect.c
+++ b/hw/usb/redirect.c
@@ -1437,8 +1437,10 @@ static void usbredir_realize(USBDevice *udev, Error **errp)
}
}
- dev->chardev_close_bh = qemu_bh_new(usbredir_chardev_close_bh, dev);
- dev->device_reject_bh = qemu_bh_new(usbredir_device_reject_bh, dev);
+ dev->chardev_close_bh = qemu_bh_new_guarded(usbredir_chardev_close_bh, dev,
+ &DEVICE(dev)->mem_reentrancy_guard);
+ dev->device_reject_bh = qemu_bh_new_guarded(usbredir_device_reject_bh, dev,
+ &DEVICE(dev)->mem_reentrancy_guard);
dev->attach_timer = timer_new_ms(QEMU_CLOCK_VIRTUAL, usbredir_do_attach, dev);
packet_id_queue_init(&dev->cancelled, dev, "cancelled");
diff --git a/hw/usb/xen-usb.c b/hw/usb/xen-usb.c
index 0f7369e7ed..dec91294ad 100644
--- a/hw/usb/xen-usb.c
+++ b/hw/usb/xen-usb.c
@@ -1021,7 +1021,8 @@ static void usbback_alloc(struct XenLegacyDevice *xendev)
QTAILQ_INIT(&usbif->req_free_q);
QSIMPLEQ_INIT(&usbif->hotplug_q);
- usbif->bh = qemu_bh_new(usbback_bh, usbif);
+ usbif->bh = qemu_bh_new_guarded(usbback_bh, usbif,
+ &DEVICE(xendev)->mem_reentrancy_guard);
}
static int usbback_free(struct XenLegacyDevice *xendev)
diff --git a/hw/virtio/virtio-balloon.c b/hw/virtio/virtio-balloon.c
index 9a4f491b54..f503572e27 100644
--- a/hw/virtio/virtio-balloon.c
+++ b/hw/virtio/virtio-balloon.c
@@ -917,8 +917,9 @@ static void virtio_balloon_device_realize(DeviceState *dev, Error **errp)
precopy_add_notifier(&s->free_page_hint_notify);
object_ref(OBJECT(s->iothread));
- s->free_page_bh = aio_bh_new(iothread_get_aio_context(s->iothread),
- virtio_ballloon_get_free_page_hints, s);
+ s->free_page_bh = aio_bh_new_guarded(iothread_get_aio_context(s->iothread),
+ virtio_ballloon_get_free_page_hints, s,
+ &dev->mem_reentrancy_guard);
}
if (virtio_has_feature(s->host_features, VIRTIO_BALLOON_F_REPORTING)) {
diff --git a/hw/virtio/virtio-crypto.c b/hw/virtio/virtio-crypto.c
index 54f9bbb789..1be7bb543c 100644
--- a/hw/virtio/virtio-crypto.c
+++ b/hw/virtio/virtio-crypto.c
@@ -817,7 +817,8 @@ static void virtio_crypto_device_realize(DeviceState *dev, Error **errp)
vcrypto->vqs[i].dataq =
virtio_add_queue(vdev, 1024, virtio_crypto_handle_dataq_bh);
vcrypto->vqs[i].dataq_bh =
- qemu_bh_new(virtio_crypto_dataq_bh, &vcrypto->vqs[i]);
+ qemu_bh_new_guarded(virtio_crypto_dataq_bh, &vcrypto->vqs[i],
+ &dev->mem_reentrancy_guard);
vcrypto->vqs[i].vcrypto = vcrypto;
}
--
2.37.3

260
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@ -0,0 +1,260 @@
From 57a26ba1c4053cdc426653f921e66f7a8efd3ce7 Mon Sep 17 00:00:00 2001
From: Thomas Huth <thuth@redhat.com>
Date: Mon, 22 May 2023 11:10:11 +0200
Subject: [PATCH 12/15] hw/scsi/lsi53c895a: Fix reentrancy issues in the LSI
controller (CVE-2023-0330)
RH-Author: Jon Maloy <jmaloy@redhat.com>
RH-MergeRequest: 277: memory: prevent dma-reentracy issues
RH-Bugzilla: 1999236
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Commit: [12/12] 28f5e04344109d8514869c50468bef481437201d (redhat/rhel/src/qemu-kvm/jons-qemu-kvm-2)
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1999236
Upstream: Merged
CVE: CVE-2021-3750
commit b987718bbb1d0eabf95499b976212dd5f0120d75
Author: Thomas Huth <thuth@redhat.com>
Date: Mon May 22 11:10:11 2023 +0200
hw/scsi/lsi53c895a: Fix reentrancy issues in the LSI controller (CVE-2023-0330)
We cannot use the generic reentrancy guard in the LSI code, so
we have to manually prevent endless reentrancy here. The problematic
lsi_execute_script() function has already a way to detect whether
too many instructions have been executed - we just have to slightly
change the logic here that it also takes into account if the function
has been called too often in a reentrant way.
The code in fuzz-lsi53c895a-test.c has been taken from an earlier
patch by Mauro Matteo Cascella.
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1563
Message-Id: <20230522091011.1082574-1-thuth@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Alexander Bulekov <alxndr@bu.edu>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jon Maloy <jmaloy@redhat.com>
---
hw/scsi/lsi53c895a.c | 23 +++--
tests/qtest/fuzz-lsi53c895a-test.c | 161 +++++++++++++++++++++++++++++
2 files changed, 178 insertions(+), 6 deletions(-)
create mode 100644 tests/qtest/fuzz-lsi53c895a-test.c
diff --git a/hw/scsi/lsi53c895a.c b/hw/scsi/lsi53c895a.c
index 2b9cb2ac5d..b60786fd56 100644
--- a/hw/scsi/lsi53c895a.c
+++ b/hw/scsi/lsi53c895a.c
@@ -1133,15 +1133,24 @@ static void lsi_execute_script(LSIState *s)
uint32_t addr, addr_high;
int opcode;
int insn_processed = 0;
+ static int reentrancy_level;
+
+ reentrancy_level++;
s->istat1 |= LSI_ISTAT1_SRUN;
again:
- if (++insn_processed > LSI_MAX_INSN) {
- /* Some windows drivers make the device spin waiting for a memory
- location to change. If we have been executed a lot of code then
- assume this is the case and force an unexpected device disconnect.
- This is apparently sufficient to beat the drivers into submission.
- */
+ /*
+ * Some windows drivers make the device spin waiting for a memory location
+ * to change. If we have executed more than LSI_MAX_INSN instructions then
+ * assume this is the case and force an unexpected device disconnect. This
+ * is apparently sufficient to beat the drivers into submission.
+ *
+ * Another issue (CVE-2023-0330) can occur if the script is programmed to
+ * trigger itself again and again. Avoid this problem by stopping after
+ * being called multiple times in a reentrant way (8 is an arbitrary value
+ * which should be enough for all valid use cases).
+ */
+ if (++insn_processed > LSI_MAX_INSN || reentrancy_level > 8) {
if (!(s->sien0 & LSI_SIST0_UDC)) {
qemu_log_mask(LOG_GUEST_ERROR,
"lsi_scsi: inf. loop with UDC masked");
@@ -1595,6 +1604,8 @@ again:
}
}
trace_lsi_execute_script_stop();
+
+ reentrancy_level--;
}
static uint8_t lsi_reg_readb(LSIState *s, int offset)
diff --git a/tests/qtest/fuzz-lsi53c895a-test.c b/tests/qtest/fuzz-lsi53c895a-test.c
new file mode 100644
index 0000000000..1b55928b9f
--- /dev/null
+++ b/tests/qtest/fuzz-lsi53c895a-test.c
@@ -0,0 +1,161 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * QTest fuzzer-generated testcase for LSI53C895A device
+ *
+ * Copyright (c) Red Hat
+ */
+
+#include "qemu/osdep.h"
+#include "libqtest.h"
+
+/*
+ * This used to trigger a DMA reentrancy issue
+ * leading to memory corruption bugs like stack
+ * overflow or use-after-free
+ * https://gitlab.com/qemu-project/qemu/-/issues/1563
+ */
+static void test_lsi_dma_reentrancy(void)
+{
+ QTestState *s;
+
+ s = qtest_init("-M q35 -m 512M -nodefaults "
+ "-blockdev driver=null-co,node-name=null0 "
+ "-device lsi53c810 -device scsi-cd,drive=null0");
+
+ qtest_outl(s, 0xcf8, 0x80000804); /* PCI Command Register */
+ qtest_outw(s, 0xcfc, 0x7); /* Enables accesses */
+ qtest_outl(s, 0xcf8, 0x80000814); /* Memory Bar 1 */
+ qtest_outl(s, 0xcfc, 0xff100000); /* Set MMIO Address*/
+ qtest_outl(s, 0xcf8, 0x80000818); /* Memory Bar 2 */
+ qtest_outl(s, 0xcfc, 0xff000000); /* Set RAM Address*/
+ qtest_writel(s, 0xff000000, 0xc0000024);
+ qtest_writel(s, 0xff000114, 0x00000080);
+ qtest_writel(s, 0xff00012c, 0xff000000);
+ qtest_writel(s, 0xff000004, 0xff000114);
+ qtest_writel(s, 0xff000008, 0xff100014);
+ qtest_writel(s, 0xff10002f, 0x000000ff);
+
+ qtest_quit(s);
+}
+
+/*
+ * This used to trigger a UAF in lsi_do_msgout()
+ * https://gitlab.com/qemu-project/qemu/-/issues/972
+ */
+static void test_lsi_do_msgout_cancel_req(void)
+{
+ QTestState *s;
+
+ if (sizeof(void *) == 4) {
+ g_test_skip("memory size too big for 32-bit build");
+ return;
+ }
+
+ s = qtest_init("-M q35 -m 2G -nodefaults "
+ "-device lsi53c895a,id=scsi "
+ "-device scsi-hd,drive=disk0 "
+ "-drive file=null-co://,id=disk0,if=none,format=raw");
+
+ qtest_outl(s, 0xcf8, 0x80000810);
+ qtest_outl(s, 0xcf8, 0xc000);
+ qtest_outl(s, 0xcf8, 0x80000810);
+ qtest_outw(s, 0xcfc, 0x7);
+ qtest_outl(s, 0xcf8, 0x80000810);
+ qtest_outl(s, 0xcfc, 0xc000);
+ qtest_outl(s, 0xcf8, 0x80000804);
+ qtest_outw(s, 0xcfc, 0x05);
+ qtest_writeb(s, 0x69736c10, 0x08);
+ qtest_writeb(s, 0x69736c13, 0x58);
+ qtest_writeb(s, 0x69736c1a, 0x01);
+ qtest_writeb(s, 0x69736c1b, 0x06);
+ qtest_writeb(s, 0x69736c22, 0x01);
+ qtest_writeb(s, 0x69736c23, 0x07);
+ qtest_writeb(s, 0x69736c2b, 0x02);
+ qtest_writeb(s, 0x69736c48, 0x08);
+ qtest_writeb(s, 0x69736c4b, 0x58);
+ qtest_writeb(s, 0x69736c52, 0x04);
+ qtest_writeb(s, 0x69736c53, 0x06);
+ qtest_writeb(s, 0x69736c5b, 0x02);
+ qtest_outl(s, 0xc02d, 0x697300);
+ qtest_writeb(s, 0x5a554662, 0x01);
+ qtest_writeb(s, 0x5a554663, 0x07);
+ qtest_writeb(s, 0x5a55466a, 0x10);
+ qtest_writeb(s, 0x5a55466b, 0x22);
+ qtest_writeb(s, 0x5a55466c, 0x5a);
+ qtest_writeb(s, 0x5a55466d, 0x5a);
+ qtest_writeb(s, 0x5a55466e, 0x34);
+ qtest_writeb(s, 0x5a55466f, 0x5a);
+ qtest_writeb(s, 0x5a345a5a, 0x77);
+ qtest_writeb(s, 0x5a345a5b, 0x55);
+ qtest_writeb(s, 0x5a345a5c, 0x51);
+ qtest_writeb(s, 0x5a345a5d, 0x27);
+ qtest_writeb(s, 0x27515577, 0x41);
+ qtest_outl(s, 0xc02d, 0x5a5500);
+ qtest_writeb(s, 0x364001d0, 0x08);
+ qtest_writeb(s, 0x364001d3, 0x58);
+ qtest_writeb(s, 0x364001da, 0x01);
+ qtest_writeb(s, 0x364001db, 0x26);
+ qtest_writeb(s, 0x364001dc, 0x0d);
+ qtest_writeb(s, 0x364001dd, 0xae);
+ qtest_writeb(s, 0x364001de, 0x41);
+ qtest_writeb(s, 0x364001df, 0x5a);
+ qtest_writeb(s, 0x5a41ae0d, 0xf8);
+ qtest_writeb(s, 0x5a41ae0e, 0x36);
+ qtest_writeb(s, 0x5a41ae0f, 0xd7);
+ qtest_writeb(s, 0x5a41ae10, 0x36);
+ qtest_writeb(s, 0x36d736f8, 0x0c);
+ qtest_writeb(s, 0x36d736f9, 0x80);
+ qtest_writeb(s, 0x36d736fa, 0x0d);
+ qtest_outl(s, 0xc02d, 0x364000);
+
+ qtest_quit(s);
+}
+
+/*
+ * This used to trigger the assert in lsi_do_dma()
+ * https://bugs.launchpad.net/qemu/+bug/697510
+ * https://bugs.launchpad.net/qemu/+bug/1905521
+ * https://bugs.launchpad.net/qemu/+bug/1908515
+ */
+static void test_lsi_do_dma_empty_queue(void)
+{
+ QTestState *s;
+
+ s = qtest_init("-M q35 -nographic -monitor none -serial none "
+ "-drive if=none,id=drive0,"
+ "file=null-co://,file.read-zeroes=on,format=raw "
+ "-device lsi53c895a,id=scsi0 "
+ "-device scsi-hd,drive=drive0,"
+ "bus=scsi0.0,channel=0,scsi-id=0,lun=0");
+ qtest_outl(s, 0xcf8, 0x80001814);
+ qtest_outl(s, 0xcfc, 0xe1068000);
+ qtest_outl(s, 0xcf8, 0x80001818);
+ qtest_outl(s, 0xcf8, 0x80001804);
+ qtest_outw(s, 0xcfc, 0x7);
+ qtest_outl(s, 0xcf8, 0x80002010);
+
+ qtest_writeb(s, 0xe106802e, 0xff); /* Fill DSP bits 16-23 */
+ qtest_writeb(s, 0xe106802f, 0xff); /* Fill DSP bits 24-31: trigger SCRIPT */
+
+ qtest_quit(s);
+}
+
+int main(int argc, char **argv)
+{
+ g_test_init(&argc, &argv, NULL);
+
+ if (!qtest_has_device("lsi53c895a")) {
+ return 0;
+ }
+
+ qtest_add_func("fuzz/lsi53c895a/lsi_do_dma_empty_queue",
+ test_lsi_do_dma_empty_queue);
+
+ qtest_add_func("fuzz/lsi53c895a/lsi_do_msgout_cancel_req",
+ test_lsi_do_msgout_cancel_req);
+
+ qtest_add_func("fuzz/lsi53c895a/lsi_dma_reentrancy",
+ test_lsi_dma_reentrancy);
+
+ return g_test_run();
+}
--
2.37.3

71
kvm-lsi53c895a-disable-reentrancy-detection-for-MMIO-reg.patch Normal file
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@ -0,0 +1,71 @@
From 8f19df61a101c1e57a1bce8adddb57a4a7123a77 Mon Sep 17 00:00:00 2001
From: Thomas Huth <thuth@redhat.com>
Date: Tue, 16 May 2023 11:05:56 +0200
Subject: [PATCH 11/15] lsi53c895a: disable reentrancy detection for MMIO
region, too
RH-Author: Jon Maloy <jmaloy@redhat.com>
RH-MergeRequest: 277: memory: prevent dma-reentracy issues
RH-Bugzilla: 1999236
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Commit: [11/12] 8016c86f8432f5ea06c831d1181e87e6d45a6a50 (redhat/rhel/src/qemu-kvm/jons-qemu-kvm-2)
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1999236
Upstream: Merged
CVE: CVE-2021-3750
commit d139fe9ad8a27bcc50b4ead77d2f97d191a0e95e
Author: Thomas Huth <thuth@redhat.com>
Date: Tue May 16 11:05:56 2023 +0200
lsi53c895a: disable reentrancy detection for MMIO region, too
While trying to use a SCSI disk on the LSI controller with an
older version of Fedora (25), I'm getting:
qemu: warning: Blocked re-entrant IO on MemoryRegion: lsi-mmio at addr: 0x34
and the SCSI controller is not usable. Seems like we have to
disable the reentrancy checker for the MMIO region, too, to
get this working again.
The problem could be reproduced it like this:
./qemu-system-x86_64 -accel kvm -m 2G -machine q35 \
-device lsi53c810,id=lsi1 -device scsi-hd,drive=d0 \
-drive if=none,id=d0,file=.../somedisk.qcow2 \
-cdrom Fedora-Everything-netinst-i386-25-1.3.iso
Where somedisk.qcow2 is an image that contains already some partitions
and file systems.
In the boot menu of Fedora, go to
"Troubleshooting" -> "Rescue a Fedora system" -> "3) Skip to shell"
Then check "dmesg | grep -i 53c" for failure messages, and try to mount
a partition from somedisk.qcow2.
Message-Id: <20230516090556.553813-1-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jon Maloy <jmaloy@redhat.com>
---
hw/scsi/lsi53c895a.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/hw/scsi/lsi53c895a.c b/hw/scsi/lsi53c895a.c
index 1e15e13fbf..2b9cb2ac5d 100644
--- a/hw/scsi/lsi53c895a.c
+++ b/hw/scsi/lsi53c895a.c
@@ -2306,6 +2306,7 @@ static void lsi_scsi_realize(PCIDevice *dev, Error **errp)
* re-entrancy guard.
*/
s->ram_io.disable_reentrancy_guard = true;
+ s->mmio_io.disable_reentrancy_guard = true;
address_space_init(&s->pci_io_as, pci_address_space_io(dev), "lsi-pci-io");
qdev_init_gpio_out(d, &s->ext_irq, 1);
--
2.37.3

59
kvm-lsi53c895a-disable-reentrancy-detection-for-script-R.patch Normal file
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@ -0,0 +1,59 @@
From 3cffdbf3224ac21016dbee69cb2382c322d4bfbb Mon Sep 17 00:00:00 2001
From: Jon Maloy <jmaloy@redhat.com>
Date: Tue, 9 May 2023 10:29:03 -0400
Subject: [PATCH 05/15] lsi53c895a: disable reentrancy detection for script RAM
RH-Author: Jon Maloy <jmaloy@redhat.com>
RH-MergeRequest: 277: memory: prevent dma-reentracy issues
RH-Bugzilla: 1999236
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Commit: [5/12] b5334c3a34b38ed1dccf0030d5704e51e00fdce3 (redhat/rhel/src/qemu-kvm/jons-qemu-kvm-2)
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1999236
Upstream: Merged
CVE: CVE-2021-3750
commit bfd6e7ae6a72b84e2eb9574f56e6ec037f05182c
Author: Alexander Bulekov <alxndr@bu.edu>
Date: Thu Apr 27 17:10:10 2023 -0400
lsi53c895a: disable reentrancy detection for script RAM
As the code is designed to use the memory APIs to access the script ram,
disable reentrancy checks for the pseudo-RAM ram_io MemoryRegion.
In the future, ram_io may be converted from an IO to a proper RAM MemoryRegion.
Reported-by: Fiona Ebner <f.ebner@proxmox.com>
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Message-Id: <20230427211013.2994127-6-alxndr@bu.edu>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jon Maloy <jmaloy@redhat.com>
---
hw/scsi/lsi53c895a.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/hw/scsi/lsi53c895a.c b/hw/scsi/lsi53c895a.c
index 85e907a785..1e15e13fbf 100644
--- a/hw/scsi/lsi53c895a.c
+++ b/hw/scsi/lsi53c895a.c
@@ -2301,6 +2301,12 @@ static void lsi_scsi_realize(PCIDevice *dev, Error **errp)
memory_region_init_io(&s->io_io, OBJECT(s), &lsi_io_ops, s,
"lsi-io", 256);
+ /*
+ * Since we use the address-space API to interact with ram_io, disable the
+ * re-entrancy guard.
+ */
+ s->ram_io.disable_reentrancy_guard = true;
+
address_space_init(&s->pci_io_as, pci_address_space_io(dev), "lsi-pci-io");
qdev_init_gpio_out(d, &s->ext_irq, 1);
--
2.37.3

151
kvm-memory-prevent-dma-reentracy-issues.patch Normal file
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@ -0,0 +1,151 @@
From e0c811c2d13f995fe1b095f48637316be5978b0e Mon Sep 17 00:00:00 2001
From: Jon Maloy <jmaloy@redhat.com>
Date: Tue, 9 May 2023 10:29:03 -0400
Subject: [PATCH 01/15] memory: prevent dma-reentracy issues
RH-Author: Jon Maloy <jmaloy@redhat.com>
RH-MergeRequest: 277: memory: prevent dma-reentracy issues
RH-Bugzilla: 1999236
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Commit: [1/12] 8fced41b4b2105343e8f0250286b771bcb43c81f (redhat/rhel/src/qemu-kvm/jons-qemu-kvm-2)
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1999236
Upstream: Merged
CVE: CVE-2021-3750
CVE: CVE-2023-0330
commit a2e1753b8054344f32cf94f31c6399a58794a380
Author: Alexander Bulekov <alxndr@bu.edu>
Date: Thu Apr 27 17:10:06 2023 -0400
memory: prevent dma-reentracy issues
Add a flag to the DeviceState, when a device is engaged in PIO/MMIO/DMA.
This flag is set/checked prior to calling a device's MemoryRegion
handlers, and set when device code initiates DMA. The purpose of this
flag is to prevent two types of DMA-based reentrancy issues:
1.) mmio -> dma -> mmio case
2.) bh -> dma write -> mmio case
These issues have led to problems such as stack-exhaustion and
use-after-frees.
Summary of the problem from Peter Maydell:
https://lore.kernel.org/qemu-devel/CAFEAcA_23vc7hE3iaM-JVA6W38LK4hJoWae5KcknhPRD5fPBZA@mail.gmail.com
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/62
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/540
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/541
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/556
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/557
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/827
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1282
Resolves: CVE-2023-0330
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20230427211013.2994127-2-alxndr@bu.edu>
[thuth: Replace warn_report() with warn_report_once()]
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jon Maloy <jmaloy@redhat.com>
---
include/exec/memory.h | 5 +++++
include/hw/qdev-core.h | 7 +++++++
softmmu/memory.c | 16 ++++++++++++++++
3 files changed, 28 insertions(+)
diff --git a/include/exec/memory.h b/include/exec/memory.h
index 20f1b27377..e089f90f9b 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -734,6 +734,8 @@ struct MemoryRegion {
bool is_iommu;
RAMBlock *ram_block;
Object *owner;
+ /* owner as TYPE_DEVICE. Used for re-entrancy checks in MR access hotpath */
+ DeviceState *dev;
const MemoryRegionOps *ops;
void *opaque;
@@ -757,6 +759,9 @@ struct MemoryRegion {
unsigned ioeventfd_nb;
MemoryRegionIoeventfd *ioeventfds;
RamDiscardManager *rdm; /* Only for RAM */
+
+ /* For devices designed to perform re-entrant IO into their own IO MRs */
+ bool disable_reentrancy_guard;
};
struct IOMMUMemoryRegion {
diff --git a/include/hw/qdev-core.h b/include/hw/qdev-core.h
index 20d3066595..14226f860d 100644
--- a/include/hw/qdev-core.h
+++ b/include/hw/qdev-core.h
@@ -162,6 +162,10 @@ struct NamedClockList {
QLIST_ENTRY(NamedClockList) node;
};
+typedef struct {
+ bool engaged_in_io;
+} MemReentrancyGuard;
+
/**
* DeviceState:
* @realized: Indicates whether the device has been fully constructed.
@@ -193,6 +197,9 @@ struct DeviceState {
int instance_id_alias;
int alias_required_for_version;
ResettableState reset;
+
+ /* Is the device currently in mmio/pio/dma? Used to prevent re-entrancy */
+ MemReentrancyGuard mem_reentrancy_guard;
};
struct DeviceListener {
diff --git a/softmmu/memory.c b/softmmu/memory.c
index 7340e19ff5..102f0a4248 100644
--- a/softmmu/memory.c
+++ b/softmmu/memory.c
@@ -541,6 +541,18 @@ static MemTxResult access_with_adjusted_size(hwaddr addr,
access_size_max = 4;
}
+ /* Do not allow more than one simultaneous access to a device's IO Regions */
+ if (mr->dev && !mr->disable_reentrancy_guard &&
+ !mr->ram_device && !mr->ram && !mr->rom_device && !mr->readonly) {
+ if (mr->dev->mem_reentrancy_guard.engaged_in_io) {
+ warn_report_once("Blocked re-entrant IO on MemoryRegion: "
+ "%s at addr: 0x%" HWADDR_PRIX,
+ memory_region_name(mr), addr);
+ return MEMTX_ACCESS_ERROR;
+ }
+ mr->dev->mem_reentrancy_guard.engaged_in_io = true;
+ }
+
/* FIXME: support unaligned access? */
access_size = MAX(MIN(size, access_size_max), access_size_min);
access_mask = MAKE_64BIT_MASK(0, access_size * 8);
@@ -555,6 +567,9 @@ static MemTxResult access_with_adjusted_size(hwaddr addr,
access_mask, attrs);
}
}
+ if (mr->dev) {
+ mr->dev->mem_reentrancy_guard.engaged_in_io = false;
+ }
return r;
}
@@ -1169,6 +1184,7 @@ static void memory_region_do_init(MemoryRegion *mr,
}
mr->name = g_strdup(name);
mr->owner = owner;
+ mr->dev = (DeviceState *) object_dynamic_cast(mr->owner, TYPE_DEVICE);
mr->ram_block = NULL;
if (name) {
--
2.37.3

68
kvm-memory-stricter-checks-prior-to-unsetting-engaged_in.patch Normal file
View File

@ -0,0 +1,68 @@
From c24e38eb508b3fb42ce3ea62fe8de0be6a95a6a8 Mon Sep 17 00:00:00 2001
From: Jon Maloy <jmaloy@redhat.com>
Date: Wed, 7 Jun 2023 11:45:09 -0400
Subject: [PATCH 10/15] memory: stricter checks prior to unsetting
engaged_in_io
RH-Author: Jon Maloy <jmaloy@redhat.com>
RH-MergeRequest: 277: memory: prevent dma-reentracy issues
RH-Bugzilla: 1999236
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Commit: [10/12] 773b62a84b2bd4f5ee7fb8e1cfb3bb91c3a01de1 (redhat/rhel/src/qemu-kvm/jons-qemu-kvm-2)
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1999236
Upstream: Merged
CVE: CVE-2021-3750
commit 3884bf6468ac6bbb58c2b3feaa74e87f821b52f3
Author: Alexander Bulekov <alxndr@bu.edu>
Date: Tue May 16 04:40:02 2023 -0400
memory: stricter checks prior to unsetting engaged_in_io
engaged_in_io could be unset by an MR with re-entrancy checks disabled.
Ensure that only MRs that can set the engaged_in_io flag can unset it.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Message-Id: <20230516084002.3813836-1-alxndr@bu.edu>
Reviewed-by: Darren Kenny <darren.kenny@oracle.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jon Maloy <jmaloy@redhat.com>
---
softmmu/memory.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/softmmu/memory.c b/softmmu/memory.c
index 102f0a4248..6b98615357 100644
--- a/softmmu/memory.c
+++ b/softmmu/memory.c
@@ -533,6 +533,7 @@ static MemTxResult access_with_adjusted_size(hwaddr addr,
unsigned access_size;
unsigned i;
MemTxResult r = MEMTX_OK;
+ bool reentrancy_guard_applied = false;
if (!access_size_min) {
access_size_min = 1;
@@ -551,6 +552,7 @@ static MemTxResult access_with_adjusted_size(hwaddr addr,
return MEMTX_ACCESS_ERROR;
}
mr->dev->mem_reentrancy_guard.engaged_in_io = true;
+ reentrancy_guard_applied = true;
}
/* FIXME: support unaligned access? */
@@ -567,7 +569,7 @@ static MemTxResult access_with_adjusted_size(hwaddr addr,
access_mask, attrs);
}
}
- if (mr->dev) {
+ if (mr->dev && reentrancy_guard_applied) {
mr->dev->mem_reentrancy_guard.engaged_in_io = false;
}
return r;
--
2.37.3

59
kvm-migration-Disable-postcopy-multifd-migration.patch Normal file
View File

@ -0,0 +1,59 @@
From dd6d0eace90285c017ae40cba0ffa95ccd963ebd Mon Sep 17 00:00:00 2001
From: Leonardo Bras <leobras@redhat.com>
Date: Tue, 20 Jun 2023 14:51:03 -0300
Subject: [PATCH 15/15] migration: Disable postcopy + multifd migration
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
RH-Author: Leonardo Brás <leobras@redhat.com>
RH-MergeRequest: 287: migration: Disable postcopy + multifd migration
RH-Bugzilla: 2169733
RH-Acked-by: Peter Xu <peterx@redhat.com>
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Commit: [1/1] 07d26fbac35b7586fe790304f03d316ed26a4ef2
Since the introduction of multifd, it's possible to perform a multifd
migration and finish it using postcopy.
A bug introduced by yank (fixed on cfc3bcf373) was previously preventing
a successful use of this migration scenario, and now thing should be
working on most scenarios.
But since there is not enough testing/support nor any reported users for
this scenario, we should disable this combination before it may cause any
problems for users.
Suggested-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Leonardo Bras <leobras@redhat.com>
Acked-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
(cherry picked from commit b405dfff1ea3cf0530b628895b5a7a50dc8c6996)
[leobras: moves logic from options.c -> migration.c and use cap_list
instead of new_caps for backward compatibility]
Signed-off-by: Leonardo Bras <leobras@redhat.com>
---
migration/migration.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/migration/migration.c b/migration/migration.c
index 817170d52d..1ad82e63f0 100644
--- a/migration/migration.c
+++ b/migration/migration.c
@@ -1246,6 +1246,11 @@ static bool migrate_caps_check(bool *cap_list,
error_setg(errp, "Postcopy is not compatible with ignore-shared");
return false;
}
+
+ if (cap_list[MIGRATION_CAPABILITY_MULTIFD]) {
+ error_setg(errp, "Postcopy is not yet compatible with multifd");
+ return false;
+ }
}
if (cap_list[MIGRATION_CAPABILITY_BACKGROUND_SNAPSHOT]) {
--
2.37.3

55
kvm-raven-disable-reentrancy-detection-for-iomem.patch Normal file
View File

@ -0,0 +1,55 @@
From c5cb3e97098834f9cf12b6c5260d9b43d68d64eb Mon Sep 17 00:00:00 2001
From: Jon Maloy <jmaloy@redhat.com>
Date: Tue, 9 May 2023 10:29:03 -0400
Subject: [PATCH 07/15] raven: disable reentrancy detection for iomem
RH-Author: Jon Maloy <jmaloy@redhat.com>
RH-MergeRequest: 277: memory: prevent dma-reentracy issues
RH-Bugzilla: 1999236
RH-Acked-by: Thomas Huth <thuth@redhat.com>
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Commit: [7/12] f41983390acba68043d386be090172dd17a5e58c (redhat/rhel/src/qemu-kvm/jons-qemu-kvm-2)
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1999236
Upstream: Merged
CVE: CVE-2021-3750
commit 6dad5a6810d9c60ca320d01276f6133bbcfa1fc7
Author: Alexander Bulekov <alxndr@bu.edu>
Date: Thu Apr 27 17:10:12 2023 -0400
raven: disable reentrancy detection for iomem
As the code is designed for re-entrant calls from raven_io_ops to
pci-conf, mark raven_io_ops as reentrancy-safe.
Signed-off-by: Alexander Bulekov <alxndr@bu.edu>
Message-Id: <20230427211013.2994127-8-alxndr@bu.edu>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Jon Maloy <jmaloy@redhat.com>
---
hw/pci-host/raven.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/hw/pci-host/raven.c b/hw/pci-host/raven.c
index 6e514f75eb..245b1653e4 100644
--- a/hw/pci-host/raven.c
+++ b/hw/pci-host/raven.c
@@ -294,6 +294,13 @@ static void raven_pcihost_initfn(Object *obj)
memory_region_init(&s->pci_memory, obj, "pci-memory", 0x3f000000);
address_space_init(&s->pci_io_as, &s->pci_io, "raven-io");
+ /*
+ * Raven's raven_io_ops use the address-space API to access pci-conf-idx
+ * (which is also owned by the raven device). As such, mark the
+ * pci_io_non_contiguous as re-entrancy safe.
+ */
+ s->pci_io_non_contiguous.disable_reentrancy_guard = true;
+
/* CPU address space */
memory_region_add_subregion(address_space_mem, PCI_IO_BASE_ADDR,
&s->pci_io);
--
2.37.3

72
kvm-target-i386-add-support-for-FB_CLEAR-feature.patch Normal file
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@ -0,0 +1,72 @@
From bf3577c044e51094ca2166e748c8bae360c3f0c2 Mon Sep 17 00:00:00 2001
From: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Date: Wed, 24 May 2023 07:26:04 -0400
Subject: [PATCH 14/15] target/i386: add support for FB_CLEAR feature
RH-Author: Emanuele Giuseppe Esposito <eesposit@redhat.com>
RH-MergeRequest: 281: target/i386: add support for FLUSH_L1D feature
RH-Bugzilla: 2216203
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Acked-by: Jon Maloy <jmaloy@redhat.com>
RH-Commit: [2/2] 8cd4b7366a9898e406ca20c9a28f14ddce855b1e
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2216203
commit 22e1094ca82d5518c1b69aff3e87c550776ae1eb
Author: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Date: Wed Feb 1 08:57:59 2023 -0500
target/i386: add support for FB_CLEAR feature
As reported by the Intel's doc:
"FB_CLEAR: The processor will overwrite fill buffer values as part of
MD_CLEAR operations with the VERW instruction.
On these processors, L1D_FLUSH does not overwrite fill buffer values."
If this cpu feature is present in host, allow QEMU to choose whether to
show it to the guest too.
One disadvantage of not exposing it is that the guest will report
a non existing vulnerability in
/sys/devices/system/cpu/vulnerabilities/mmio_stale_data
because the mitigation is present only when the cpu has
(FLUSH_L1D and MD_CLEAR) or FB_CLEAR
features enabled.
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20230201135759.555607-3-eesposit@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
---
target/i386/cpu.c | 2 +-
target/i386/cpu.h | 1 +
2 files changed, 2 insertions(+), 1 deletion(-)
diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 47da059df6..9d3dcdcc0d 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -981,7 +981,7 @@ FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
"ssb-no", "mds-no", "pschange-mc-no", "tsx-ctrl",
"taa-no", NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
- NULL, NULL, NULL, NULL,
+ NULL, "fb-clear", NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
NULL, NULL, NULL, NULL,
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 7cb7cea8ab..9b7d664ee7 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -950,6 +950,7 @@ uint64_t x86_cpu_get_supported_feature_word(FeatureWord w,
#define MSR_ARCH_CAP_PSCHANGE_MC_NO (1U << 6)
#define MSR_ARCH_CAP_TSX_CTRL_MSR (1U << 7)
#define MSR_ARCH_CAP_TAA_NO (1U << 8)
+#define MSR_ARCH_CAP_FB_CLEAR (1U << 17)
#define MSR_CORE_CAP_SPLIT_LOCK_DETECT (1U << 5)
--
2.37.3

71
kvm-target-i386-add-support-for-FLUSH_L1D-feature.patch Normal file
View File

@ -0,0 +1,71 @@
From 9cfedd3a9880390ddda25a235b999430c3dd5e83 Mon Sep 17 00:00:00 2001
From: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Date: Wed, 24 May 2023 07:25:57 -0400
Subject: [PATCH 13/15] target/i386: add support for FLUSH_L1D feature
RH-Author: Emanuele Giuseppe Esposito <eesposit@redhat.com>
RH-MergeRequest: 281: target/i386: add support for FLUSH_L1D feature
RH-Bugzilla: 2216203
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Acked-by: Jon Maloy <jmaloy@redhat.com>
RH-Commit: [1/2] 50c54ca7c734dc2b9303e724a6c5ac1127472271
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2216203
commit 0e7e3bf1a552c178924867fa7c2f30ccc8a179e0
Author: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Date: Wed Feb 1 08:57:58 2023 -0500
target/i386: add support for FLUSH_L1D feature
As reported by Intel's doc:
"L1D_FLUSH: Writeback and invalidate the L1 data cache"
If this cpu feature is present in host, allow QEMU to choose whether to
show it to the guest too.
One disadvantage of not exposing it is that the guest will report
a non existing vulnerability in
/sys/devices/system/cpu/vulnerabilities/mmio_stale_data
because the mitigation is present only when the cpu has
(FLUSH_L1D and MD_CLEAR) or FB_CLEAR
features enabled.
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Message-Id: <20230201135759.555607-2-eesposit@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
---
target/i386/cpu.c | 2 +-
target/i386/cpu.h | 2 ++
2 files changed, 3 insertions(+), 1 deletion(-)
diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 0543b846ff..47da059df6 100644
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -857,7 +857,7 @@ FeatureWordInfo feature_word_info[FEATURE_WORDS] = {
"tsx-ldtrk", NULL, NULL /* pconfig */, NULL,
NULL, NULL, "amx-bf16", "avx512-fp16",
"amx-tile", "amx-int8", "spec-ctrl", "stibp",
- NULL, "arch-capabilities", "core-capability", "ssbd",
+ "flush-l1d", "arch-capabilities", "core-capability", "ssbd",
},
.cpuid = {
.eax = 7,
diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 5d2ddd81b9..7cb7cea8ab 100644
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -864,6 +864,8 @@ uint64_t x86_cpu_get_supported_feature_word(FeatureWord w,
#define CPUID_7_0_EDX_SPEC_CTRL (1U << 26)
/* Single Thread Indirect Branch Predictors */
#define CPUID_7_0_EDX_STIBP (1U << 27)
+/* Flush L1D cache */
+#define CPUID_7_0_EDX_FLUSH_L1D (1U << 28)
/* Arch Capabilities */
#define CPUID_7_0_EDX_ARCH_CAPABILITIES (1U << 29)
/* Core Capability */
--
2.37.3

55
qemu-kvm.spec
View File

@ -83,7 +83,7 @@ Obsoletes: %1-rhev <= %{epoch}:%{version}-%{release}
Summary: QEMU is a machine emulator and virtualizer
Name: qemu-kvm
Version: 6.2.0
Release: 35%{?rcrel}%{?dist}
Release: 36%{?rcrel}%{?dist}
# Epoch because we pushed a qemu-1.0 package. AIUI this can't ever be dropped
Epoch: 15
License: GPLv2 and GPLv2+ and CC-BY
@ -729,6 +729,36 @@ Patch284: kvm-target-s390x-tcg-mem_helper-Test-the-right-bits-in-p.patch
# For bz#2169308 - Backport latest s390x-related fixes from upstream QEMU for qemu-kvm in RHEL 8.9
# For bz#2209605 - [IBM 8.9 FEAT] KVM: ECKD List Directed IPL - virtio (qemu)
Patch285: kvm-pc-bios-Add-support-for-List-Directed-IPL-from-ECKD-.patch
# For bz#1999236 - CVE-2021-3750 virt:rhel/qemu-kvm: QEMU: hcd-ehci: DMA reentrancy issue leads to use-after-free [rhel-8]
Patch286: kvm-memory-prevent-dma-reentracy-issues.patch
# For bz#1999236 - CVE-2021-3750 virt:rhel/qemu-kvm: QEMU: hcd-ehci: DMA reentrancy issue leads to use-after-free [rhel-8]
Patch287: kvm-async-Add-an-optional-reentrancy-guard-to-the-BH-API.patch
# For bz#1999236 - CVE-2021-3750 virt:rhel/qemu-kvm: QEMU: hcd-ehci: DMA reentrancy issue leads to use-after-free [rhel-8]
Patch288: kvm-checkpatch-add-qemu_bh_new-aio_bh_new-checks.patch
# For bz#1999236 - CVE-2021-3750 virt:rhel/qemu-kvm: QEMU: hcd-ehci: DMA reentrancy issue leads to use-after-free [rhel-8]
Patch289: kvm-hw-replace-most-qemu_bh_new-calls-with-qemu_bh_new_g.patch
# For bz#1999236 - CVE-2021-3750 virt:rhel/qemu-kvm: QEMU: hcd-ehci: DMA reentrancy issue leads to use-after-free [rhel-8]
Patch290: kvm-lsi53c895a-disable-reentrancy-detection-for-script-R.patch
# For bz#1999236 - CVE-2021-3750 virt:rhel/qemu-kvm: QEMU: hcd-ehci: DMA reentrancy issue leads to use-after-free [rhel-8]
Patch291: kvm-bcm2835_property-disable-reentrancy-detection-for-io.patch
# For bz#1999236 - CVE-2021-3750 virt:rhel/qemu-kvm: QEMU: hcd-ehci: DMA reentrancy issue leads to use-after-free [rhel-8]
Patch292: kvm-raven-disable-reentrancy-detection-for-iomem.patch
# For bz#1999236 - CVE-2021-3750 virt:rhel/qemu-kvm: QEMU: hcd-ehci: DMA reentrancy issue leads to use-after-free [rhel-8]
Patch293: kvm-apic-disable-reentrancy-detection-for-apic-msi.patch
# For bz#1999236 - CVE-2021-3750 virt:rhel/qemu-kvm: QEMU: hcd-ehci: DMA reentrancy issue leads to use-after-free [rhel-8]
Patch294: kvm-async-avoid-use-after-free-on-re-entrancy-guard.patch
# For bz#1999236 - CVE-2021-3750 virt:rhel/qemu-kvm: QEMU: hcd-ehci: DMA reentrancy issue leads to use-after-free [rhel-8]
Patch295: kvm-memory-stricter-checks-prior-to-unsetting-engaged_in.patch
# For bz#1999236 - CVE-2021-3750 virt:rhel/qemu-kvm: QEMU: hcd-ehci: DMA reentrancy issue leads to use-after-free [rhel-8]
Patch296: kvm-lsi53c895a-disable-reentrancy-detection-for-MMIO-reg.patch
# For bz#1999236 - CVE-2021-3750 virt:rhel/qemu-kvm: QEMU: hcd-ehci: DMA reentrancy issue leads to use-after-free [rhel-8]
Patch297: kvm-hw-scsi-lsi53c895a-Fix-reentrancy-issues-in-the-LSI-.patch
# For bz#2216203 - [qemu-kvm]VM reports vulnerabilty to mmio_stale_data on patched host with microcode
Patch298: kvm-target-i386-add-support-for-FLUSH_L1D-feature.patch
# For bz#2216203 - [qemu-kvm]VM reports vulnerabilty to mmio_stale_data on patched host with microcode
Patch299: kvm-target-i386-add-support-for-FB_CLEAR-feature.patch
# For bz#2169733 - Qemu on destination host crashed if migrate with postcopy and multifd enabled
Patch300: kvm-migration-Disable-postcopy-multifd-migration.patch
BuildRequires: wget
BuildRequires: rpm-build
@ -1898,6 +1928,29 @@ sh %{_sysconfdir}/sysconfig/modules/kvm.modules &> /dev/null || :
%changelog
* Thu Jun 29 2023 Jon Maloy <jmaloy@redhat.com> - 6.2.0-36
- kvm-memory-prevent-dma-reentracy-issues.patch [bz#1999236]
- kvm-async-Add-an-optional-reentrancy-guard-to-the-BH-API.patch [bz#1999236]
- kvm-checkpatch-add-qemu_bh_new-aio_bh_new-checks.patch [bz#1999236]
- kvm-hw-replace-most-qemu_bh_new-calls-with-qemu_bh_new_g.patch [bz#1999236]
- kvm-lsi53c895a-disable-reentrancy-detection-for-script-R.patch [bz#1999236]
- kvm-bcm2835_property-disable-reentrancy-detection-for-io.patch [bz#1999236]
- kvm-raven-disable-reentrancy-detection-for-iomem.patch [bz#1999236]
- kvm-apic-disable-reentrancy-detection-for-apic-msi.patch [bz#1999236]
- kvm-async-avoid-use-after-free-on-re-entrancy-guard.patch [bz#1999236]
- kvm-memory-stricter-checks-prior-to-unsetting-engaged_in.patch [bz#1999236]
- kvm-lsi53c895a-disable-reentrancy-detection-for-MMIO-reg.patch [bz#1999236]
- kvm-hw-scsi-lsi53c895a-Fix-reentrancy-issues-in-the-LSI-.patch [bz#1999236]
- kvm-target-i386-add-support-for-FLUSH_L1D-feature.patch [bz#2216203]
- kvm-target-i386-add-support-for-FB_CLEAR-feature.patch [bz#2216203]
- kvm-migration-Disable-postcopy-multifd-migration.patch [bz#2169733]
- Resolves: bz#1999236
(CVE-2021-3750 virt:rhel/qemu-kvm: QEMU: hcd-ehci: DMA reentrancy issue leads to use-after-free [rhel-8])
- Resolves: bz#2216203
([qemu-kvm]VM reports vulnerabilty to mmio_stale_data on patched host with microcode)
- Resolves: bz#2169733
(Qemu on destination host crashed if migrate with postcopy and multifd enabled)
* Fri Jun 02 2023 Jon Maloy <jmaloy@redhat.com> - 6.2.0-35
- kvm-virtiofsd-Add-basic-support-for-FUSE_SYNCFS-request.patch [bz#2196880]
- kvm-s390-kvm-adjust-diag318-resets-to-retain-data.patch [bz#2169308 bz#2209605]