[PATCH AUTOSEL 4.14 23/66] media: isif: reset global state

From: Sasha Levin
Date: Tue Dec 22 2020 - 21:40:30 EST


From: Evgeny Novikov <novikov@xxxxxxxxx>

[ Upstream commit 6651dba2bd838f34cf5a1e84229aaa579b1a94fe ]

isif_probe() invokes iounmap() on error handling paths, but it does not
reset the global state. So, later it can invoke iounmap() even when
ioremap() fails. This is the case also for isif_remove(). The patch
resets the global state after invoking iounmap() to avoid this.

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Evgeny Novikov <novikov@xxxxxxxxx>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/media/platform/davinci/isif.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/media/platform/davinci/isif.c b/drivers/media/platform/davinci/isif.c
index 12065ad1ac457..e7372319de80d 100644
--- a/drivers/media/platform/davinci/isif.c
+++ b/drivers/media/platform/davinci/isif.c
@@ -1086,10 +1086,14 @@ static int isif_probe(struct platform_device *pdev)
release_mem_region(res->start, resource_size(res));
i--;
fail_nobase_res:
- if (isif_cfg.base_addr)
+ if (isif_cfg.base_addr) {
iounmap(isif_cfg.base_addr);
- if (isif_cfg.linear_tbl0_addr)
+ isif_cfg.base_addr = NULL;
+ }
+ if (isif_cfg.linear_tbl0_addr) {
iounmap(isif_cfg.linear_tbl0_addr);
+ isif_cfg.linear_tbl0_addr = NULL;
+ }

while (i >= 0) {
res = platform_get_resource(pdev, IORESOURCE_MEM, i);
@@ -1107,8 +1111,11 @@ static int isif_remove(struct platform_device *pdev)
int i = 0;

iounmap(isif_cfg.base_addr);
+ isif_cfg.base_addr = NULL;
iounmap(isif_cfg.linear_tbl0_addr);
+ isif_cfg.linear_tbl0_addr = NULL;
iounmap(isif_cfg.linear_tbl1_addr);
+ isif_cfg.linear_tbl1_addr = NULL;
while (i < 3) {
res = platform_get_resource(pdev, IORESOURCE_MEM, i);
if (res)
--
2.27.0