[PATCH 5.15.y] media: saa7164: fix cleanup on resource allocation failure

[Sasha Levin <sashal@kernel.org>]

From: Guangshuo Li <lgs201920130244@gmail.com>

[ Upstream commit 28e84c6e2e6753ed238ea097b2842a32a6a6879b ]

saa7164_dev_setup() adds the device to the global saa7164_devlist before
requesting the PCI BAR memory regions.

If get_resources() fails, saa7164_dev_setup() decrements the device count
and returns an error, but leaves the device on saa7164_devlist. The probe
error path then frees the device, leaving a dangling entry on the global
list.

Reuse the existing MMIO mapping error path to remove the device from
saa7164_devlist and decrement the device count before returning.

Also release BAR0 if it was successfully requested but the BAR2 request
fails.

Fixes: 443c1228d505 ("V4L/DVB (12923): SAA7164: Add support for the NXP SAA7164 silicon")
Cc: stable@vger.kernel.org
Signed-off-by: Guangshuo Li <lgs201920130244@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>
[ Inlined err_devlist cleanup with explicit mutex locking because the shared MMIO cleanup path is absent. ]
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/media/pci/saa7164/saa7164-core.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/media/pci/saa7164/saa7164-core.c b/drivers/media/pci/saa7164/saa7164-core.c
index c10997e2271d2..6691042cc4211 100644
--- a/drivers/media/pci/saa7164/saa7164-core.c
+++ b/drivers/media/pci/saa7164/saa7164-core.c
@@ -880,6 +880,9 @@ static int get_resources(struct saa7164_dev *dev)
 		if (request_mem_region(pci_resource_start(dev->pci, 2),
 			pci_resource_len(dev->pci, 2), dev->name))
 			return 0;
+
+		release_mem_region(pci_resource_start(dev->pci, 0),
+				   pci_resource_len(dev->pci, 0));
 	}
 
 	printk(KERN_ERR "%s: can't get MMIO memory @ 0x%llx or 0x%llx\n",
@@ -993,6 +996,9 @@ static int saa7164_dev_setup(struct saa7164_dev *dev)
 		       dev->name, dev->pci->subsystem_vendor,
 		       dev->pci->subsystem_device);
 
+		mutex_lock(&devlist);
+		list_del(&dev->devlist);
+		mutex_unlock(&devlist);
 		saa7164_devcount--;
 		return -ENODEV;
 	}
-- 
2.53.0