On 4/19/21 3:32 PM, Peter Maydell wrote: > On Sun, 18 Apr 2021 at 06:30, Philippe Mathieu-Daudé <[email protected]> > wrote: >> >> From: Michael Tokarev <[email protected]> >> >> 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: [email protected] >> Signed-off-by: Michael Tokarev <[email protected]> >> Reviewed-by: Philippe Mathieu-Daudé <[email protected]> >> Message-Id: <[email protected]> >> Reported-by: Cheolwoo Myung <[email protected]> >> 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 <[email protected]> >> --- >> Supersedes: <[email protected]> >> >> MJT patch: >> https://www.mail-archive.com/[email protected]/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
What a shame... Sorry, v3 coming.
