[PATCH 67/69] video: imsttfb: check for ioremap() failures

Greg Kroah-Hartman
2021-05-03T12:02:58Z

We should check if ioremap() were to somehow fail in imsttfb_probe() and
handle the unwinding of the resources allocated here properly.

Ideally if anyone cares about this driver (it's for a PowerMac era PCI
display card), they wouldn't even be using fbdev anymore. Or the devm_*
apis could be used, but that's just extra work for diminishing
returns...

Cc: Finn Thain <fthain@telegraphics.com.au>
Cc: Rob Herring <robh@kernel.org>
Cc: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/video/fbdev/imsttfb.c | 21 ++++++++++++++++++---
1 file changed, 18 insertions(+), 3 deletions(-)

diff --git a/drivers/video/fbdev/imsttfb.c b/drivers/video/fbdev/imsttfb.c
index e04411701ec8..16f272a50811 100644
--- a/drivers/video/fbdev/imsttfb.c
+++ b/drivers/video/fbdev/imsttfb.c
@@ -1469,6 +1469,7 @@ static int imsttfb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
struct imstt_par *par;
struct fb_info *info;
struct device_node *dp;
+ int ret = -ENOMEM;

dp = pci_device_to_OF_node(pdev);
if(dp)
@@ -1504,23 +1505,37 @@ static int imsttfb_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
default:
printk(KERN_INFO "imsttfb: Device 0x%x unknown, "
"contact maintainer.\n", pdev->device);
- release_mem_region(addr, size);
- framebuffer_release(info);
- return -ENODEV;
+ ret = -ENODEV;
+ goto error;
}

info->fix.smem_start = addr;
info->screen_base = (__u8 *)ioremap(addr, par->ramdac == IBM ?
0x400000 : 0x800000);
+ if (!info->screen_base)
+ goto error;
info->fix.mmio_start = addr + 0x800000;
par->dc_regs = ioremap(addr + 0x800000, 0x1000);
+ if (!par->dc_regs)
+ goto error;
par->cmap_regs_phys = addr + 0x840000;
par->cmap_regs = (__u8 *)ioremap(addr + 0x840000, 0x1000);
+ if (!par->cmap_regs)
+ goto error;
info->pseudo_palette = par->palette;
init_imstt(info);

pci_set_drvdata(pdev, info);
return 0;
+
+error:
+ if (par->dc_regs)
+ iounmap(par->dc_regs);
+ if (info->screen_base)
+ iounmap(info->screen_base);
+ release_mem_region(addr, size);
+ framebuffer_release(info);
+ return ret;
}

static void imsttfb_remove(struct pci_dev *pdev)
--
2.31.1