2021-03-22 00:31:53

by Tong Zhang

Subject: [PATCH 0/2] scsi: myrb: fix null-ptr-dereference issues

This series fixes two null-ptr-dereference issues in the myrb driver.
Both are caused by uninitialized variables.

Tong Zhang (2):
scsi: myrb: fix null-ptr-dereference in myrb_cleanup
scsi: myrb: fix null-ptr-dereference in myrb_probe

drivers/scsi/myrb.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

--
2.25.1

2021-03-22 00:32:05

by Tong Zhang

Subject: [PATCH 1/2] scsi: myrb: fix null-ptr-dereference in myrb_cleanup

cb->disable_intr may not be set yet when myrb_cleanup is called.
check before using this function pointer.

[ 1.410913] BUG: kernel NULL pointer dereference, address: 0000000000000000
[ 1.411273] #PF: supervisor instruction fetch in kernel mode
[ 1.411566] #PF: error_code(0x0010) - not-present page
[ 1.413138] RIP: 0010:0x0
[ 1.417711] myrb_cleanup+0x13f/0x1b0 [myrb]
[ 1.417939] myrb_probe.cold+0xc6/0x6fc [myrb]

Signed-off-by: Tong Zhang <[email protected]>
---
drivers/scsi/myrb.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/myrb.c b/drivers/scsi/myrb.c
index 3d8e91c07dc7..ee33d97fb92c 100644
--- a/drivers/scsi/myrb.c
+++ b/drivers/scsi/myrb.c
@@ -1240,7 +1240,8 @@ static void myrb_cleanup(struct myrb_hba *cb)
myrb_unmap(cb);

if (cb->mmio_base) {
- cb->disable_intr(cb->io_base);
+ if (cb->disable_intr)
+ cb->disable_intr(cb->io_base);
iounmap(cb->mmio_base);
}
if (cb->irq)
--
2.25.1

2021-03-22 00:34:55

by Tong Zhang

Subject: [PATCH 2/2] scsi: myrb: fix null-ptr-dereference in myrb_probe

cb->host should be initialized and set before it is used by the
following probe logic and the interrupt handler etc.

[ 5.073493] BUG: kernel NULL pointer dereference, address: 00000000000002cc
[ 5.075907] RIP: 0010:kobject_put+0x25/0x120
[ 5.081572] Call Trace:
[ 5.081720] myrb_probe.cold+0x22/0xabc [myrb]
[ 5.083510] local_pci_probe+0x6f/0xb0

Fixes: 081ff398c56c ("scsi: myrb: Add Mylex RAID controller (block interface)")
Signed-off-by: Tong Zhang <[email protected]>
---
drivers/scsi/myrb.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/scsi/myrb.c b/drivers/scsi/myrb.c
index ee33d97fb92c..7de49b869128 100644
--- a/drivers/scsi/myrb.c
+++ b/drivers/scsi/myrb.c
@@ -3512,6 +3512,7 @@ static struct myrb_hba *myrb_detect(struct pci_dev *pdev,
shost->max_cmd_len = 12;
shost->max_lun = 256;
cb = shost_priv(shost);
+ cb->host = shost;
mutex_init(&cb->dcmd_mutex);
mutex_init(&cb->dma_mutex);
cb->pdev = pdev;
--
2.25.1