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qemu-kvm/SOURCES/kvm-lsi53c895a-disable-reen...

60 lines
2.1 KiB

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