qemu-kvm/kvm-async-avoid-use-after-free-on-re-entrancy-guard.patch
Miroslav Rezanina a799a516c5 * Tue Jun 13 2023 Miroslav Rezanina <mrezanin@redhat.com> - 8.0.0-5
- kvm-block-compile-out-assert_bdrv_graph_readable-by-defa.patch [bz#2186725]
- kvm-graph-lock-Disable-locking-for-now.patch [bz#2186725]
- kvm-nbd-server-Fix-drained_poll-to-wake-coroutine-in-rig.patch [bz#2186725]
- kvm-iotests-Test-commit-with-iothreads-and-ongoing-I-O.patch [bz#2186725]
- kvm-memory-prevent-dma-reentracy-issues.patch [RHEL-516]
- kvm-async-Add-an-optional-reentrancy-guard-to-the-BH-API.patch [RHEL-516]
- kvm-checkpatch-add-qemu_bh_new-aio_bh_new-checks.patch [RHEL-516]
- kvm-hw-replace-most-qemu_bh_new-calls-with-qemu_bh_new_g.patch [RHEL-516]
- kvm-lsi53c895a-disable-reentrancy-detection-for-script-R.patch [RHEL-516]
- kvm-bcm2835_property-disable-reentrancy-detection-for-io.patch [RHEL-516]
- kvm-raven-disable-reentrancy-detection-for-iomem.patch [RHEL-516]
- kvm-apic-disable-reentrancy-detection-for-apic-msi.patch [RHEL-516]
- kvm-async-avoid-use-after-free-on-re-entrancy-guard.patch [RHEL-516]
- kvm-loongarch-mark-loongarch_ipi_iocsr-re-entrnacy-safe.patch [RHEL-516]
- kvm-memory-stricter-checks-prior-to-unsetting-engaged_in.patch [RHEL-516]
- kvm-lsi53c895a-disable-reentrancy-detection-for-MMIO-reg.patch [RHEL-516]
- kvm-hw-scsi-lsi53c895a-Fix-reentrancy-issues-in-the-LSI-.patch [RHEL-516]
- kvm-hw-pci-Disable-PCI_ERR_UNCOR_MASK-register-for-machi.patch [bz#2189423]
- kvm-multifd-Fix-the-number-of-channels-ready.patch [bz#2196289]
- kvm-util-async-teardown-wire-up-query-command-line-optio.patch [bz#2168500]
- kvm-s390x-pv-Fix-spurious-warning-with-asynchronous-tear.patch [bz#2168500]
- Resolves: bz#2186725
  (Qemu hang when commit during fio running(iothread enable))
- Resolves: RHEL-516
  (CVE-2023-2680 qemu-kvm: QEMU: hcd-ehci: DMA reentrancy issue (incomplete fix for CVE-2021-3750) [rhel-9])
- Resolves: bz#2189423
  (Failed to migrate VM from rhel 9.3 to rhel 9.2)
- Resolves: bz#2196289
  (Fix number of ready channels on multifd)
- Resolves: bz#2168500
  ([IBM 9.3 FEAT] KVM: Improve memory reclaiming for z15 Secure Execution guests - qemu part)
2023-06-13 05:19:43 -04:00

71 lines
2.4 KiB
Diff

From 137e84f68da06666ebf7f391766cc6209ce1c39c Mon Sep 17 00:00:00 2001
From: Jon Maloy <jmaloy@redhat.com>
Date: Tue, 9 May 2023 10:29:03 -0400
Subject: [PATCH 13/21] async: avoid use-after-free on re-entrancy guard
RH-Author: Jon Maloy <jmaloy@redhat.com>
RH-MergeRequest: 165: memory: prevent dma-reentracy issues
RH-Jira: RHEL-516
RH-Acked-by: Miroslav Rezanina <mrezanin@redhat.com>
RH-Commit: [9/13] d4b957108aaacf4a597122aaeeaa8e56985f1fca (jmaloy/jmaloy-qemu-kvm-2)
Jira: https://issues.redhat.com/browse/RHEL-516
Upstream: Merged
CVE: CVE-2023-2680
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 a9b528c370..cd1a1815f9 100644
--- a/util/async.c
+++ b/util/async.c
@@ -156,18 +156,20 @@ 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;
}
}
--
2.39.3