From 4367a20cc442c56b05611b4224de9a61908f9eac Mon Sep 17 00:00:00 2001 From: Mauro Matteo Cascella Date: Mon, 11 Jul 2022 14:33:16 +0200 Subject: [PATCH] scsi/lsi53c895a: really fix use-after-free in lsi_do_msgout (CVE-2022-0216) Set current_req to NULL, not current_req->req, to prevent reusing a free'd buffer in case of repeated SCSI cancel requests. Also apply the fix to CLEAR QUEUE and BUS DEVICE RESET messages as well, since they also cancel the request. Thanks to Alexander Bulekov for providing a reproducer. Fixes: CVE-2022-0216 Resolves: https://gitlab.com/qemu-project/qemu/-/issues/972 Signed-off-by: Mauro Matteo Cascella Tested-by: Alexander Bulekov Message-Id: <20220711123316.421279-1-mcascell@redhat.com> Signed-off-by: Paolo Bonzini https://gitlab.com/qemu-project/qemu/-/commit/4367a20cc4 CVE: CVE-2022-0216 Upstream-Status: Backport Signed-off-by: Chee Yang Lee --- hw/scsi/lsi53c895a.c | 3 +- 1 files changed, 2 insertions(+), 1 deletion(-) diff --git a/hw/scsi/lsi53c895a.c b/hw/scsi/lsi53c895a.c index 99ea42d49b..ad5f5e5f39 100644 --- a/hw/scsi/lsi53c895a.c +++ b/hw/scsi/lsi53c895a.c @@ -1030,7 +1030,7 @@ static void lsi_do_msgout(LSIState *s) trace_lsi_do_msgout_abort(current_tag); if (current_req && current_req->req) { scsi_req_cancel(current_req->req); - current_req->req = NULL; + current_req = NULL; } lsi_disconnect(s); break; @@ -1056,6 +1056,7 @@ static void lsi_do_msgout(LSIState *s) /* clear the current I/O process */ if (s->current) { scsi_req_cancel(s->current->req); + current_req = NULL; } /* As the current implemented devices scsi_disk and scsi_generic -- GitLab