[PATCH 5.16 0855/1017] media: atomisp: fix bad usage at error handling logic

Greg Kroah-Hartman
2022-04-05T13:41:59Z

From: Mauro Carvalho Chehab <mchehab@kernel.org>

[ Upstream commit fc0b582c858ed73f94c8f3375c203ea46f1f7402 ]

As warned by sparse:
atomisp: drivers/staging/media/atomisp/pci/atomisp_acc.c:508 atomisp_acc_load_extensions() warn: iterator used outside loop: 'acc_fw'

The acc_fw interactor is used outside the loop, at the error handling
logic. On most cases, this is actually safe there, but, if
atomisp_css_set_acc_parameters() has an error, an attempt to use it
will pick an invalid value for acc_fw.

Reported-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
.../staging/media/atomisp/pci/atomisp_acc.c | 28 +++++++++++++------
1 file changed, 19 insertions(+), 9 deletions(-)

diff --git a/drivers/staging/media/atomisp/pci/atomisp_acc.c b/drivers/staging/media/atomisp/pci/atomisp_acc.c
index 9a1751895ab0..28cb271663c4 100644
--- a/drivers/staging/media/atomisp/pci/atomisp_acc.c
+++ b/drivers/staging/media/atomisp/pci/atomisp_acc.c
@@ -439,6 +439,18 @@ int atomisp_acc_s_mapped_arg(struct atomisp_sub_device *asd,
return 0;
}

+static void atomisp_acc_unload_some_extensions(struct atomisp_sub_device *asd,
+ int i,
+ struct atomisp_acc_fw *acc_fw)
+{
+ while (--i >= 0) {
+ if (acc_fw->flags & acc_flag_to_pipe[i].flag) {
+ atomisp_css_unload_acc_extension(asd, acc_fw->fw,
+ acc_flag_to_pipe[i].pipe_id);
+ }
+ }
+}
+
/*
* Appends the loaded acceleration binary extensions to the
* current ISP mode. Must be called just before sh_css_start().
@@ -479,16 +491,20 @@ int atomisp_acc_load_extensions(struct atomisp_sub_device *asd)
acc_fw->fw,
acc_flag_to_pipe[i].pipe_id,
acc_fw->type);
- if (ret)
+ if (ret) {
+ atomisp_acc_unload_some_extensions(asd, i, acc_fw);
goto error;
+ }

ext_loaded = true;
}
}

ret = atomisp_css_set_acc_parameters(acc_fw);
- if (ret < 0)
+ if (ret < 0) {
+ atomisp_acc_unload_some_extensions(asd, i, acc_fw);
goto error;
+ }
}

if (!ext_loaded)
@@ -497,6 +513,7 @@ int atomisp_acc_load_extensions(struct atomisp_sub_device *asd)
ret = atomisp_css_update_stream(asd);
if (ret) {
dev_err(isp->dev, "%s: update stream failed.\n", __func__);
+ atomisp_acc_unload_extensions(asd);
goto error;
}

@@ -504,13 +521,6 @@ int atomisp_acc_load_extensions(struct atomisp_sub_device *asd)
return 0;

error:
- while (--i >= 0) {
- if (acc_fw->flags & acc_flag_to_pipe[i].flag) {
- atomisp_css_unload_acc_extension(asd, acc_fw->fw,
- acc_flag_to_pipe[i].pipe_id);
- }
- }
-
list_for_each_entry_continue_reverse(acc_fw, &asd->acc.fw, list) {
if (acc_fw->type != ATOMISP_ACC_FW_LOAD_TYPE_OUTPUT &&
acc_fw->type != ATOMISP_ACC_FW_LOAD_TYPE_VIEWFINDER)
--
2.34.1