File scsi-lsi53c895a-fix-use-after-free-in-ls.patch of Package qemu.28027

From: Mauro Matteo Cascella <mcascell@redhat.com>
Date: Tue, 5 Jul 2022 22:05:43 +0200
Subject: scsi/lsi53c895a: fix use-after-free in lsi_do_msgout (CVE-2022-0216)

Git-commit: 6c8fa961da5e60f574bb52fd3ad44b1e9e8ad4b8
References: bsc#1198038, CVE-2022-0216

Set current_req->req to NULL to prevent reusing a free'd buffer in case of
repeated SCSI cancel requests. Thanks to Thomas Huth for suggesting the patch.

Fixes: CVE-2022-0216
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/972
Signed-off-by: Mauro Matteo Cascella <mcascell@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Message-Id: <20220705200543.2366809-1-mcascell@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Dario Faggioli <dfaggioli@suse.com>
---
 hw/scsi/lsi53c895a.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/hw/scsi/lsi53c895a.c b/hw/scsi/lsi53c895a.c
index 85e907a7854a8aeaa812978675cd..8033cf05023de397e91a0a121449 100644
--- a/hw/scsi/lsi53c895a.c
+++ b/hw/scsi/lsi53c895a.c
@@ -1029,8 +1029,9 @@ static void lsi_do_msgout(LSIState *s)
         case 0x0d:
             /* The ABORT TAG message clears the current I/O process only. */
             trace_lsi_do_msgout_abort(current_tag);
-            if (current_req) {
+            if (current_req && current_req->req) {
                 scsi_req_cancel(current_req->req);
+                current_req->req = NULL;
             }
             lsi_disconnect(s);
             break;