media: pci: cx23885: Fix the error handling in cx23885_initdev()

When the driver fails to call the dma_set_mask(), the driver will get
the following splat:

[   55.853884] BUG: KASAN: use-after-free in __process_removed_driver+0x3c/0x240
[   55.854486] Read of size 8 at addr ffff88810de60408 by task modprobe/590
[   55.856822] Call Trace:
[   55.860327]  __process_removed_driver+0x3c/0x240
[   55.861347]  bus_for_each_dev+0x102/0x160
[   55.861681]  i2c_del_driver+0x2f/0x50

This is because the driver has initialized the i2c related resources
in cx23885_dev_setup() but not released them in error handling, fix this
bug by modifying the error path that jumps after failing to call the
dma_set_mask().

Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

diff --git a/drivers/media/pci/cx23885/cx23885-core.c b/drivers/media/pci/cx23885/cx23885-core.c
index f8f2ff3..a07b18f 100644 (file)
--- a/drivers/media/pci/cx23885/cx23885-core.c
+++ b/drivers/media/pci/cx23885/cx23885-core.c
@@ -2165,7 +2165,7 @@ static int cx23885_initdev(struct pci_dev *pci_dev,
        err = dma_set_mask(&pci_dev->dev, 0xffffffff);
        if (err) {
                pr_err("%s/0: Oops: no 32bit PCI DMA ???\n", dev->name);
-               goto fail_ctrl;
+               goto fail_dma_set_mask;
        }
 
        err = request_irq(pci_dev->irq, cx23885_irq,
@@ -2173,7 +2173,7 @@ static int cx23885_initdev(struct pci_dev *pci_dev,
        if (err < 0) {
                pr_err("%s: can't get IRQ %d\n",
                       dev->name, pci_dev->irq);
-               goto fail_irq;
+               goto fail_dma_set_mask;
        }
 
        switch (dev->board) {
@@ -2195,7 +2195,7 @@ static int cx23885_initdev(struct pci_dev *pci_dev,
 
        return 0;
 
-fail_irq:
+fail_dma_set_mask:
        cx23885_dev_unregister(dev);
 fail_ctrl:
        v4l2_ctrl_handler_free(hdl);