On 26/10/2018 14:33, P J P wrote: > From: Prasad J Pandit <p...@fedoraproject.org> > > While performing PowerNV memory r/w operations, the access length > 'sz' could exceed the data[4] buffer size. Add check to avoid OOB > access. > > Reported-by: Moguofang <moguof...@huawei.com> > Signed-off-by: Prasad J Pandit <p...@fedoraproject.org> > --- > hw/ppc/pnv_lpc.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > Update v2: add error log message > -> https://lists.gnu.org/archive/html/qemu-devel/2018-10/msg05750.html > > diff --git a/hw/ppc/pnv_lpc.c b/hw/ppc/pnv_lpc.c > index d7721320a2..172a915cfc 100644 > --- a/hw/ppc/pnv_lpc.c > +++ b/hw/ppc/pnv_lpc.c > @@ -155,9 +155,15 @@ static void pnv_lpc_do_eccb(PnvLpcController *lpc, > uint64_t cmd) > /* XXX Check for magic bits at the top, addr size etc... */ > unsigned int sz = (cmd & ECCB_CTL_SZ_MASK) >> ECCB_CTL_SZ_LSH; > uint32_t opb_addr = cmd & ECCB_CTL_ADDR_MASK; > - uint8_t data[4]; > + uint8_t data[8]; > bool success;
I'm not sure 8 is enough. ECCB_CTL_SZ_MASK is PPC_BITMASK(4, 7), and ECCB_CTL_SZ_LSH is (63 - 7). So the bitmask is 4 bits wide, and thus sz can be 0 to 15. I think data[] size should be 16. Thanks, Laurent