[PATCH][media-next] media: venus: fix loop wrap in cleanup of clks

From: Colin King
Date: Thu Jun 22 2017 - 13:27:34 EST


From: Colin Ian King <colin.king@xxxxxxxxxxxxx>

The current pre-decrement is incorrect and should be replaced
with a post-decrement. Consider the case where the very first
clk_prepare_enable fails when i is 0; in this case the error
clean up will decrement the unsigned int which wraps to the
largest unsigned int value causing an array out of bounds read
on core->clks[i].

Detected by CoverityScan, CID#1446590 ("Out-of-bounds read")

Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
---
drivers/media/platform/qcom/venus/core.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/media/platform/qcom/venus/core.c b/drivers/media/platform/qcom/venus/core.c
index 776d2bae6979..d8cbe8549d97 100644
--- a/drivers/media/platform/qcom/venus/core.c
+++ b/drivers/media/platform/qcom/venus/core.c
@@ -137,7 +137,7 @@ static int venus_clks_enable(struct venus_core *core)

return 0;
err:
- while (--i)
+ while (i--)
clk_disable_unprepare(core->clks[i]);

return ret;
--
2.11.0