Hi Hans,
On Sun, Jul 30, 2023 at 11:33 PM Hans de Goede <hdegoede@xxxxxxxxxx> wrote:
>
> The atomisp code base has a custom assert() macro, a couple of functions
> use this in a construction like the following:
>
> assert(pipe);
> assert(pipe->stream);
> if ((!pipe) || (!pipe->stream)) {
> ia_css_debug_dtrace(IA_CSS_DEBUG_TRACE_PRIVATE,
> "allocate_mipi_frames(%p) exit: ...\n",
> pipe);
> return -EINVAL;
> }
>
> The second assert is seen by smatch as dereferencing "pipe" in the above
> example (and dereferencing "dvs_6axis_config" in the other case).
>
> Following by the dereferenced variable being checked (a second time)
> in the following if () statement.
>
> This triggers the following smatch warnings:
> drivers/staging/media/atomisp/pci/sh_css_mipi.c:356 allocate_mipi_frames() warn: variable dereferenced before check 'pipe' (see line 355)
> drivers/staging/media/atomisp/pci/sh_css_mipi.c:562 send_mipi_frames() warn: variable dereferenced before check 'pipe' (see line 561)
> drivers/staging/media/atomisp/pci/sh_css_param_dvs.c:208 free_dvs_6axis_table() warn: variable dereferenced before check 'dvs_6axis_config' (see line 206)
>
> The custom assert() macro actually expands to a BUG() call and BUG()
> calls should not be used in the kernel.
>
> Remove the assert() calls to fix the smatch warnings and in case of
> [allocate|send]_mipi_frames() also remove the if () return -EINVAL
> block since these functions are never called with a NULL pipe.
>
> Reported-by: Hans Verkuil <hverkuil@xxxxxxxxx>
> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
> ---
> Note:
> 1. No Closes: tag since Hans Verkuil reported this in an offlist email.
> 2. All the other assert() calls really should also be removed.
> I've put this on my todo list.
> ---
> Changes in v2:
> - Drop the sh_css_sp.c bits, just dropping the assert() calls is
> not enough there
> ---
> drivers/staging/media/atomisp/pci/sh_css_mipi.c | 16 ----------------
> .../staging/media/atomisp/pci/sh_css_param_dvs.c | 3 ---
> 2 files changed, 19 deletions(-)
>
> diff --git a/drivers/staging/media/atomisp/pci/sh_css_mipi.c b/drivers/staging/media/atomisp/pci/sh_css_mipi.c
> index b20acaab0595..ced21dedf7ac 100644
> --- a/drivers/staging/media/atomisp/pci/sh_css_mipi.c
> +++ b/drivers/staging/media/atomisp/pci/sh_css_mipi.c
> @@ -351,15 +351,6 @@ allocate_mipi_frames(struct ia_css_pipe *pipe,
> ia_css_debug_dtrace(IA_CSS_DEBUG_TRACE_PRIVATE,
> "allocate_mipi_frames(%p) enter:\n", pipe);
>
> - assert(pipe);
> - assert(pipe->stream);
> - if ((!pipe) || (!pipe->stream)) {
> - ia_css_debug_dtrace(IA_CSS_DEBUG_TRACE_PRIVATE,
> - "allocate_mipi_frames(%p) exit: pipe or stream is null.\n",
> - pipe);
> - return -EINVAL;
> - }
Thank you for working on this.
The NULL test for pipe could be kept here since the caller only tests
"stream" but not test "main_pipe" is NULL. (sh_css.c line: 1799)
The rest of the part is ok for me.
> -
> if (IS_ISP2401 && pipe->stream->config.online) {
> ia_css_debug_dtrace(IA_CSS_DEBUG_TRACE_PRIVATE,
> "allocate_mipi_frames(%p) exit: no buffers needed for 2401 pipe mode.\n",
> @@ -557,13 +548,6 @@ send_mipi_frames(struct ia_css_pipe *pipe)
>
> IA_CSS_ENTER_PRIVATE("pipe=%p", pipe);
>
> - assert(pipe);
> - assert(pipe->stream);
> - if (!pipe || !pipe->stream) {
> - IA_CSS_ERROR("pipe or stream is null");
> - return -EINVAL;
> - }
> -
> /* multi stream video needs mipi buffers */
> /* nothing to be done in other cases. */
> if (pipe->stream->config.mode != IA_CSS_INPUT_MODE_BUFFERED_SENSOR) {
> diff --git a/drivers/staging/media/atomisp/pci/sh_css_param_dvs.c b/drivers/staging/media/atomisp/pci/sh_css_param_dvs.c
> index ff0082d02af3..5174bc210ae1 100644
> --- a/drivers/staging/media/atomisp/pci/sh_css_param_dvs.c
> +++ b/drivers/staging/media/atomisp/pci/sh_css_param_dvs.c
> @@ -202,9 +202,6 @@ generate_dvs_6axis_table_from_config(struct ia_css_dvs_6axis_config
> void
> free_dvs_6axis_table(struct ia_css_dvs_6axis_config **dvs_6axis_config)
> {
> - assert(dvs_6axis_config);
> - assert(*dvs_6axis_config);
> -
> if ((dvs_6axis_config) && (*dvs_6axis_config)) {
> IA_CSS_ENTER_PRIVATE("dvs_6axis_config %p", (*dvs_6axis_config));
> if ((*dvs_6axis_config)->xcoords_y) {
> --
> 2.41.0
>
--
BR,
Kate
