[PATCH 5.4 027/411] media: pci: cx23885: Fix the error handling in cx23885_initdev()

Greg Kroah-Hartman
2022-06-13T10:59:55Z

From: Zheyu Ma <zheyuma97@gmail.com>

[ Upstream commit e8123311cf06d7dae71e8c5fe78e0510d20cd30b ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/media/pci/cx23885/cx23885-core.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/media/pci/cx23885/cx23885-core.c b/drivers/media/pci/cx23885/cx23885-core.c
index ead0acb7807c..6747ecb4911b 100644
--- a/drivers/media/pci/cx23885/cx23885-core.c
+++ b/drivers/media/pci/cx23885/cx23885-core.c
@@ -2154,7 +2154,7 @@ static int cx23885_initdev(struct pci_dev *pci_dev,
err = pci_set_dma_mask(pci_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,
@@ -2162,7 +2162,7 @@ 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) {
@@ -2184,7 +2184,7 @@ 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);
--
2.35.1