[PATCH v1] edac: i82975x_edac :- Handle return NULL error from ioremap_nocache

From: Arvind Yadav
Date: Mon Jan 16 2017 - 01:45:31 EST


Here, If ioremap_nocache will fail. It will return NULL.
Kernel can run into a NULL-pointer dereference.
This error check will avoid NULL pointer dereference.

Signed-off-by: Arvind Yadav <arvind.yadav.cs@xxxxxxxxx>
---
drivers/edac/i82975x_edac.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/edac/i82975x_edac.c b/drivers/edac/i82975x_edac.c
index 7baa8ac..e747d82 100644
--- a/drivers/edac/i82975x_edac.c
+++ b/drivers/edac/i82975x_edac.c
@@ -494,6 +494,10 @@ static int i82975x_probe1(struct pci_dev *pdev, int dev_idx)
}
mchbar &= 0xffffc000; /* bits 31:14 used for 16K window */
mch_window = ioremap_nocache(mchbar, 0x1000);
+ if (!mch_window) {
+ edac_dbg(3, "failed to memory map!\n");
+ goto fail0;
+ }

#ifdef i82975x_DEBUG_IOMEM
i82975x_printk(KERN_INFO, "MCHBAR real = %0x, remapped = %p\n",
--
1.9.1