2018-08-29 15:42:23

by George Kennedy

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

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 <[email protected]>
Signed-off-by: George Kennedy <[email protected]>
Reviewed-by: Mark Kanda <[email protected]>
---
drivers/scsi/sym53c8xx_2/sym_hipd.c | 15 +++++++++++----
1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/scsi/sym53c8xx_2/sym_hipd.c b/drivers/scsi/sym53c8xx_2/sym_hipd.c
index bd3f6e2..0a2a545 100644
--- a/drivers/scsi/sym53c8xx_2/sym_hipd.c
+++ b/drivers/scsi/sym53c8xx_2/sym_hipd.c
@@ -4370,6 +4370,13 @@ static void sym_nego_rejected(struct sym_hcb *np, struct sym_tcb *tp, struct sym
OUTB(np, HS_PRT, HS_BUSY);
}

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

2018-08-29 16:58:30

by Andy Shevchenko

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

On Wed, Aug 29, 2018 at 6:42 PM George Kennedy
<[email protected]> 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 <[email protected]>
> Signed-off-by: George Kennedy <[email protected]>
> Reviewed-by: Mark Kanda <[email protected]>

> +#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

2018-09-12 00:56:07

by Martin K. Petersen

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

Matthew,

> I don't think that's worth doing. Let's keep the patch simple like
> this.

Applied to 4.20/scsi-queue, thanks!

--
Martin K. Petersen Oracle Linux Engineering