On Mon, May 22, 2017 at 09:29:41AM -0700, Kees Cook wrote: > On Mon, May 22, 2017 at 8:05 AM, Varun Prakash <varun@xxxxxxxxxxx> wrote: > > On Tue, May 09, 2017 at 03:34:44PM -0700, Kees Cook wrote: > >> When copying attributes, the len argument was padded out and the resulting > >> memcpy() would copy beyond the end of the source buffer. Avoid this, > >> and use size_t for val_len to avoid all the casts. Similarly, avoid source > >> buffer casts and use void *. > >> > >> Additionally enforces val_len can be represented by u16 and that > >> the DMA buffer was not overflowed. Fixes the size of mfa, which is not > >> FC_FDMI_PORT_ATTR_MAXFRAMESIZE_LEN (but it will be padded up to 4). This > >> was noticed by the future CONFIG_FORTIFY_SOURCE checks. > >> > >> Cc: Daniel Micay <danielmicay@xxxxxxxxx> > >> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> > >> --- > >> drivers/scsi/csiostor/csio_lnode.c | 43 +++++++++++++++++++++++--------------- > >> 1 file changed, 26 insertions(+), 17 deletions(-) > >> > >> diff --git a/drivers/scsi/csiostor/csio_lnode.c b/drivers/scsi/csiostor/csio_lnode.c > >> index c00b2ff72b55..be5ee2d37815 100644 > >> --- a/drivers/scsi/csiostor/csio_lnode.c > >> +++ b/drivers/scsi/csiostor/csio_lnode.c > >> @@ -238,14 +238,23 @@ csio_osname(uint8_t *buf, size_t buf_len) > >> } > >> > > > > > >> > >> csio_append_attrib(&pld, FC_FDMI_HBA_ATTR_MAXCTPAYLOAD, > >> - (uint8_t *)&maxpayload, > >> - FC_FDMI_HBA_ATTR_MAXCTPAYLOAD_LEN); > >> + &maxpayload, FC_FDMI_HBA_ATTR_MAXCTPAYLOAD_LEN); > >> len = (uint32_t)(pld - (uint8_t *)cmd); > >> numattrs++; > >> attrib_blk->numattrs = htonl(numattrs); > >> @@ -1794,6 +1801,8 @@ csio_ln_mgmt_submit_req(struct csio_ioreq *io_req, > >> struct csio_mgmtm *mgmtm = csio_hw_to_mgmtm(hw); > >> int rv; > >> > >> + BUG_ON(pld_len > pld->len); > >> + > > > > I think WARN_ON() is better than BUG_ON() in this case > > > > if (WARN_ON(pld_len > pld->len)) > > return -EINVAL; > > > >> io_req->io_cbfn = io_cbfn; /* Upper layer callback handler */ > >> io_req->fw_handle = (uintptr_t) (io_req); > >> io_req->eq_idx = mgmtm->eq_idx; > > I chose BUG_ON here because the damage has already been done. If this > assertion is hit, the heap buffers have already been overrun. This > isn't a state we should only warn about... > Ok. Acked-by: Varun Prakash <varun@xxxxxxxxxxx>
