From 3bf92c57253fdf61bdf0502c31dba5e215dfb192 Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Wed, 22 Feb 2012 14:11:21 +0100 Subject: [PATCH 005/109] qiov: prevent double free or use-after-free RH-Author: Paolo Bonzini Message-id: <1329919979-20948-5-git-send-email-pbonzini@redhat.com> Patchwork-id: 37486 O-Subject: [RHEL 6.3 qemu-kvm PATCH v2 004/102] qiov: prevent double free or use-after-free Bugzilla: 782029 RH-Acked-by: Gerd Hoffmann RH-Acked-by: Laszlo Ersek RH-Acked-by: Orit Wasserman qemu_iovec_destroy does not clear the QEMUIOVector fully, and the data could thus be used after free or freed again. While I do not know any example in the tree, I observed this using virtio-scsi (and SCSI scatter/gather) when canceling DMA requests. Signed-off-by: Paolo Bonzini Signed-off-by: Kevin Wolf (cherry picked from bd83b3620517ef9f2079cfda465953e60263f623) Conflicts: cutils.c (qemu_free vs. g_free) --- cutils.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) Signed-off-by: Michal Novotny --- cutils.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) diff --git a/cutils.c b/cutils.c index 94d58da..0edbbfd 100644 --- a/cutils.c +++ b/cutils.c @@ -217,7 +217,10 @@ void qemu_iovec_destroy(QEMUIOVector *qiov) { assert(qiov->nalloc != -1); + qemu_iovec_reset(qiov); qemu_free(qiov->iov); + qiov->nalloc = 0; + qiov->iov = NULL; } void qemu_iovec_reset(QEMUIOVector *qiov) -- 1.7.7.6