On Wed, Mar 21, 2018 at 09:12:00PM -0400, Martin K. Petersen wrote:
>
> Varun: Please look at this. Thanks!
>
> > What happened to this one?
> >
> > regards,
> > dan carpenter
> >
> >
> > On Wed, Nov 29, 2017 at 02:42:20PM +0300, Dan Carpenter wrote:
> >> The story is that Smatch marks skb->data as untrusted and so it
> >> complains about this code:
> >>
> >> drivers/scsi/cxgbi/cxgb4i/cxgb4i.c:2111 t4_uld_rx_handler()
> >> error: buffer overflow 'cxgb4i_cplhandlers' 239 <= 255.
> >>
> >> I don't know the code very well, but it looks like a reasonable warning
> >> message. Let's address it by adding a sanity check to make sure "opc"
> >> is within bounds.
> >>
> >> Fixes: bbc02c7e9d34 ("cxgb4: Add register, message, and FW definitions")
> >> Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> >>
> >> diff --git a/drivers/scsi/cxgbi/cxgb4i/cxgb4i.c b/drivers/scsi/cxgbi/cxgb4i/cxgb4i.c
> >> index 266eddf17a99..94b2d5660a07 100644
> >> --- a/drivers/scsi/cxgbi/cxgb4i/cxgb4i.c
> >> +++ b/drivers/scsi/cxgbi/cxgb4i/cxgb4i.c
> >> @@ -2108,12 +2108,12 @@ static int t4_uld_rx_handler(void *handle, const __be64 *rsp,
> >> log_debug(1 << CXGBI_DBG_TOE,
> >> "cdev %p, opcode 0x%x(0x%x,0x%x), skb %p.\n",
> >> cdev, opc, rpl->ot.opcode_tid, ntohl(rpl->ot.opcode_tid), skb);
> >> - if (cxgb4i_cplhandlers[opc])
> >> - cxgb4i_cplhandlers[opc](cdev, skb);
> >> - else {
> >> + if (opc >= ARRAY_SIZE(cxgb4i_cplhandlers) || !cxgb4i_cplhandlers[opc]) {
> >> pr_err("No handler for opcode 0x%x.\n", opc);
> >> __kfree_skb(skb);
> >> + return 0;
> >> }
> >> + cxgb4i_cplhandlers[opc](cdev, skb);
> >> return 0;
> >> nomem:
> >> log_debug(1 << CXGBI_DBG_TOE, "OOM bailing out.\n");
> >
> >
This check is not necessary but we can add it to avoid warning.
The commit mentioned in "Fixes" is not correct, this code was added in commit
"7b36b6e [SCSI] cxgb4i v5: iscsi driver"
Acked-by: Varun Prakash <varun@xxxxxxxxxxx>
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