Re: [PATCH] sym53c8xx: fix NULL pointer dereference panic in sym_int_sir() in sym_hipd.c

From: Andy Shevchenko
Date: Wed Aug 29 2018 - 12:56:37 EST


On Wed, Aug 29, 2018 at 6:42 PM George Kennedy
<george.kennedy@xxxxxxxxxx> wrote:
>
> sym_int_sir() in sym_hipd.c does not check the command pointer for NULL
> before using it in debug message prints.
>
> Suggested-by: Matthew Wilcox <matthew.wilcox@xxxxxxxxxx>
> Signed-off-by: George Kennedy <george.kennedy@xxxxxxxxxx>
> Reviewed-by: Mark Kanda <mark.kanda@xxxxxxxxxx>

> +#define sym_printk(lvl, tp, cp, fmt, v...) do { \

Since all users are KERN_WARNING level, perhaps

sym_pr_warn(tp, ...) ... \
... \
..._printk(KERN_WARNING ...

?

> + if (cp) \
> + scmd_printk(lvl, cp->cmd, fmt, ##v); \
> + else \
> + starget_printk(lvl, tp->starget, fmt, ##v); \
> +} while (0)
> +
> /*
> * chip exception handler for programmed interrupts.
> */
> @@ -4415,7 +4422,7 @@ static void sym_int_sir(struct sym_hcb *np)
> * been selected with ATN. We do not want to handle that.
> */
> case SIR_SEL_ATN_NO_MSG_OUT:
> - scmd_printk(KERN_WARNING, cp->cmd,
> + sym_printk(KERN_WARNING, tp, cp,
> "No MSG OUT phase after selection with ATN\n");
> goto out_stuck;
> /*
> @@ -4423,7 +4430,7 @@ static void sym_int_sir(struct sym_hcb *np)
> * having reselected the initiator.
> */
> case SIR_RESEL_NO_MSG_IN:
> - scmd_printk(KERN_WARNING, cp->cmd,
> + sym_printk(KERN_WARNING, tp, cp,
> "No MSG IN phase after reselection\n");
> goto out_stuck;
> /*
> @@ -4431,7 +4438,7 @@ static void sym_int_sir(struct sym_hcb *np)
> * an IDENTIFY.
> */
> case SIR_RESEL_NO_IDENTIFY:
> - scmd_printk(KERN_WARNING, cp->cmd,
> + sym_printk(KERN_WARNING, tp, cp,
> "No IDENTIFY after reselection\n");
> goto out_stuck;
> /*
> @@ -4460,7 +4467,7 @@ static void sym_int_sir(struct sym_hcb *np)
> case SIR_RESEL_ABORTED:
> np->lastmsg = np->msgout[0];
> np->msgout[0] = M_NOOP;
> - scmd_printk(KERN_WARNING, cp->cmd,
> + sym_printk(KERN_WARNING, tp, cp,
> "message %x sent on bad reselection\n", np->lastmsg);
> goto out;
> /*
> --
> 1.8.3.1
>


--
With Best Regards,
Andy Shevchenko