Re: [PATCH] PPC: CELLEB - fix potential NULL pointer dereference

From: Cyrill Gorcunov
Date: Thu Nov 29 2007 - 00:41:53 EST


On 11/29/07, Ishizaki Kou <kou.ishizaki@xxxxxxxxxxxxx> wrote:
[...snip...]
>
> There is no problem to use Michael's part, and I also prefer simple
> one like this.
>
> Cyrill, would you please update your patch?
>
> Best regards,
> Kou Ishizaki
>

Please see updated patch enveloped. (Can't do it inline becase I'm on
my work now where I have no Linux machine)

Cyrill
---
From: Cyrill Gorcunov <gorcunov@xxxxxxxxx>
Subject: [PATCH] PPC: CELLEB - fix possible NULL pointer dereference

This patch adds checking for NULL returned value to
prevent possible NULL pointer dereference.

Signed-off-by: Cyrill Gorcunov <gorcunov@xxxxxxxxx>
---

arch/powerpc/platforms/celleb/pci.c | 11 ++++++++---
1 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/platforms/celleb/pci.c b/arch/powerpc/platforms/celleb/pci.c
index 6bc32fd..13ec4a6 100644
--- a/arch/powerpc/platforms/celleb/pci.c
+++ b/arch/powerpc/platforms/celleb/pci.c
@@ -138,8 +138,6 @@ static void celleb_config_read_fake(unsigned char *config, int where,
*val = celleb_fake_config_readl(p);
break;
}
-
- return;
}

static void celleb_config_write_fake(unsigned char *config, int where,
@@ -158,7 +156,6 @@ static void celleb_config_write_fake(unsigned char *config, int where,
celleb_fake_config_writel(val, p);
break;
}
- return;
}

static int celleb_fake_pci_read_config(struct pci_bus *bus,
@@ -351,6 +348,10 @@ static int __init celleb_setup_fake_pci_device(struct device_node *node,
wi1 = of_get_property(node, "vendor-id", NULL);
wi2 = of_get_property(node, "class-code", NULL);
wi3 = of_get_property(node, "revision-id", NULL);
+ if (!wi0 || !wi1 || !wi2 || !wi3) {
+ printk(KERN_ERR "PCI: Missing device tree properties.\n");
+ goto error;
+ }

celleb_config_write_fake(*config, PCI_DEVICE_ID, 2, wi0[0] & 0xffff);
celleb_config_write_fake(*config, PCI_VENDOR_ID, 2, wi1[0] & 0xffff);
@@ -372,6 +373,10 @@ static int __init celleb_setup_fake_pci_device(struct device_node *node,
celleb_setup_pci_base_addrs(hose, devno, fn, num_base_addr);

li = of_get_property(node, "interrupts", &rlen);
+ if (!li) {
+ printk(KERN_ERR "PCI: interrupts not found.\n");
+ goto error;
+ }
val = li[0];
celleb_config_write_fake(*config, PCI_INTERRUPT_PIN, 1, 1);
celleb_config_write_fake(*config, PCI_INTERRUPT_LINE, 1, val);