From: Wenwen Wang wang6495@umn.edu
[ Upstream commit a26ac6c1bed951b2066cc4b2257facd919e35c0b ]
In isif_probe(), there is a while loop to get the ISIF base address and linearization table0 and table1 address. In the loop body, the function platform_get_resource() is called to get the resource. If platform_get_resource() returns NULL, the loop is terminated and the execution goes to 'fail_nobase_res'. Suppose the loop is terminated at the first iteration because platform_get_resource() returns NULL and the execution goes to 'fail_nobase_res'. Given that there is another while loop at 'fail_nobase_res' and i equals to 0, one iteration of the second while loop will be executed. However, the second while loop does not check the return value of platform_get_resource(). This can cause a NULL pointer dereference bug if the return value is a NULL pointer.
This patch avoids the above issue by adding a check in the second while loop after the call to platform_get_resource().
Signed-off-by: Wenwen Wang wang6495@umn.edu Signed-off-by: Hans Verkuil hverkuil@xs4all.nl Signed-off-by: Mauro Carvalho Chehab mchehab+samsung@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/media/platform/davinci/isif.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/media/platform/davinci/isif.c b/drivers/media/platform/davinci/isif.c index f924e76e2fbf8..340f8218f54d3 100644 --- a/drivers/media/platform/davinci/isif.c +++ b/drivers/media/platform/davinci/isif.c @@ -1100,7 +1100,8 @@ static int isif_probe(struct platform_device *pdev)
while (i >= 0) { res = platform_get_resource(pdev, IORESOURCE_MEM, i); - release_mem_region(res->start, resource_size(res)); + if (res) + release_mem_region(res->start, resource_size(res)); i--; } vpfe_unregister_ccdc_device(&isif_hw_dev);