[PATCH AUTOSEL 4.9 41/64] scsi: sym53c8xx: fix NULL pointer dereference panic in sym_int_sir()

Sasha Levin
2019-11-08T11:47:01Z

From: George Kennedy <george.kennedy@oracle.com>

[ Upstream commit 288315e95264b6355e26609e9dec5dc4563d4ab0 ]

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@oracle.com>
Signed-off-by: George Kennedy <george.kennedy@oracle.com>
Reviewed-by: Mark Kanda <mark.kanda@oracle.com>
Acked-by: Matthew Wilcox <matthew.wilcox@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
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 c6425e3df5a04..f1c7714377524 100644
--- a/drivers/scsi/sym53c8xx_2/sym_hipd.c
+++ b/drivers/scsi/sym53c8xx_2/sym_hipd.c
@@ -4371,6 +4371,13 @@ 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.
*/
@@ -4416,7 +4423,7 @@ 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;
/*
@@ -4424,7 +4431,7 @@ 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;
/*
@@ -4432,7 +4439,7 @@ 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;
/*
@@ -4461,7 +4468,7 @@ 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;
/*
--
2.20.1