On Sun, 18 Apr 2021 at 06:30, Philippe Mathieu-Daudé <phi...@redhat.com> wrote: > > From: Michael Tokarev <m...@tls.msk.ru> > > While processing SCSI i/o requests in mptsas_process_scsi_io_request(), > the Megaraid emulator appends new MPTSASRequest object 'req' to > the 's->pending' queue. In case of an error, this same object gets > dequeued in mptsas_free_request() only if SCSIRequest object > 'req->sreq' is initialised. This may lead to a use-after-free issue. > > Since s->pending is actually not used, simply remove it from > MPTSASState. > > Cc: qemu-sta...@nongnu.org > Signed-off-by: Michael Tokarev <m...@tls.msk.ru> > Reviewed-by: Philippe Mathieu-Daudé <phi...@redhat.com> > Message-Id: <20210416102243.1293871-1-...@msgid.tls.msk.ru> > Reported-by: Cheolwoo Myung <cwmy...@snu.ac.kr> > BugLink: https://bugs.launchpad.net/qemu/+bug/1914236 (CVE-2021-3392) > Fixes: e351b826112 ("hw: Add support for LSI SAS1068 (mptsas) device") > [PMD: Reworded description, added more tags] > Signed-off-by: Philippe Mathieu-Daudé <phi...@redhat.com> > --- > Supersedes: <20210416102243.1293871-1-...@msgid.tls.msk.ru> > > MJT patch: > https://www.mail-archive.com/qemu-devel@nongnu.org/msg799236.html > > Since rc4 is soon, I'm directly respining his patch with my comments > addressed. > > This is not a new regression (present since QEMU v2.6.0) but is a > CVE... > > PJP first patch: > https://lists.gnu.org/archive/html/qemu-devel/2021-02/msg02660.html > --- > hw/scsi/mptsas.h | 1 - > hw/scsi/mptsas.c | 4 ---- > 2 files changed, 5 deletions(-)
This fails to compile: ../../hw/scsi/mptsas.c: In function ‘mptsas_free_request’: ../../hw/scsi/mptsas.c:254:18: error: unused variable ‘s’ [-Werror=unused-variable] MPTSASState *s = req->dev; ^ cc1: all warnings being treated as errors thanks -- PMM