[PATCH] media: atomisp: don't pass a pointer to a local variable

From: Mauro Carvalho Chehab
Date: Fri May 13 2022 - 04:23:54 EST


As warned by gcc 12.1:

drivers/staging/media/atomisp/pci/runtime/rmgr/src/rmgr_vbuf.c: In function 'ia_css_rmgr_acq_vbuf':
drivers/staging/media/atomisp/pci/runtime/rmgr/src/rmgr_vbuf.c:275:33: error: storing the address of local variable 'h' in '*handle' [-Werror=dangling-pointer=]
275 | *handle = &h;
| ~~~~~~~~^~~~
drivers/staging/media/atomisp/pci/runtime/rmgr/src/rmgr_vbuf.c:257:40: note: 'h' declared here
257 | struct ia_css_rmgr_vbuf_handle h;
| ^
drivers/staging/media/atomisp/pci/runtime/rmgr/src/rmgr_vbuf.c:257:40: note: 'handle' declared here
cc1: all warnings being treated as errors

The logic uses a temporary struct to update the handler, but,
instead of copying the value to the pointer sent by the caller, it
replaces it with the content with a local variable. That's wrong, and
may lead the caller to use a weird value.

Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx>
---
.../staging/media/atomisp/pci/runtime/rmgr/src/rmgr_vbuf.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/staging/media/atomisp/pci/runtime/rmgr/src/rmgr_vbuf.c b/drivers/staging/media/atomisp/pci/runtime/rmgr/src/rmgr_vbuf.c
index d96aaa4bc75d..39604752785b 100644
--- a/drivers/staging/media/atomisp/pci/runtime/rmgr/src/rmgr_vbuf.c
+++ b/drivers/staging/media/atomisp/pci/runtime/rmgr/src/rmgr_vbuf.c
@@ -254,7 +254,7 @@ void rmgr_pop_handle(struct ia_css_rmgr_vbuf_pool *pool,
void ia_css_rmgr_acq_vbuf(struct ia_css_rmgr_vbuf_pool *pool,
struct ia_css_rmgr_vbuf_handle **handle)
{
- struct ia_css_rmgr_vbuf_handle h;
+ struct ia_css_rmgr_vbuf_handle h = { 0 };

if ((!pool) || (!handle) || (!*handle)) {
IA_CSS_LOG("Invalid inputs");
@@ -272,7 +272,7 @@ void ia_css_rmgr_acq_vbuf(struct ia_css_rmgr_vbuf_pool *pool,
h.size = (*handle)->size;
/* release ref to current buffer */
ia_css_rmgr_refcount_release_vbuf(handle);
- *handle = &h;
+ **handle = h;
}
/* get new buffer for needed size */
if ((*handle)->vptr == 0x0) {
--
2.36.1