On 05/01/2021 13:49, Sakari Ailus wrote:
> GCC with W=2 level of kernel compiler warnings warns about the use of
> uninitialised variables in a few locations. While these uninitialised
> variables were not used in reality, this still produced compiler warnings.
>
> Address this by assigning the variables to NULL and checking for NULL in
> places it is not expected, returning -EPROTO in that case. This provides
> at least some sanity checking at runtime as the compiler appears unable to
> do that at compile time.
>
> Reported-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
> Signed-off-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
Acked-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx>
This fixes the warnings!
Thank you,
Hans
> ---
> drivers/media/i2c/ccs/ccs-data.c | 24 ++++++++++++++++++++----
> 1 file changed, 20 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/media/i2c/ccs/ccs-data.c b/drivers/media/i2c/ccs/ccs-data.c
> index 59338a6704af..99b2b515058a 100644
> --- a/drivers/media/i2c/ccs/ccs-data.c
> +++ b/drivers/media/i2c/ccs/ccs-data.c
> @@ -214,7 +214,7 @@ static int ccs_data_parse_regs(struct bin_container *bin,
> size_t *__num_regs, const void *payload,
> const void *endp, struct device *dev)
> {
> - struct ccs_reg *regs_base, *regs;
> + struct ccs_reg *regs_base = NULL, *regs = NULL;
> size_t num_regs = 0;
> u16 addr = 0;
>
> @@ -285,6 +285,9 @@ static int ccs_data_parse_regs(struct bin_container *bin,
> if (!bin->base) {
> bin_reserve(bin, len);
> } else if (__regs) {
> + if (!regs)
> + return -EPROTO;
> +
> regs->addr = addr;
> regs->len = len;
> regs->value = bin_alloc(bin, len);
> @@ -305,8 +308,12 @@ static int ccs_data_parse_regs(struct bin_container *bin,
> if (__num_regs)
> *__num_regs = num_regs;
>
> - if (bin->base && __regs)
> + if (bin->base && __regs) {
> + if (!regs_base)
> + return -EPROTO;
> +
> *__regs = regs_base;
> + }
>
> return 0;
> }
> @@ -425,7 +432,7 @@ static int ccs_data_parse_rules(struct bin_container *bin,
> size_t *__num_rules, const void *payload,
> const void *endp, struct device *dev)
> {
> - struct ccs_rule *rules_base, *rules = NULL, *next_rule;
> + struct ccs_rule *rules_base = NULL, *rules = NULL, *next_rule = NULL;
> size_t num_rules = 0;
> const void *__next_rule = payload;
> int rval;
> @@ -483,6 +490,9 @@ static int ccs_data_parse_rules(struct bin_container *bin,
> } else {
> unsigned int i;
>
> + if (!next_rule)
> + return -EPROTO;
> +
> rules = next_rule;
> next_rule++;
>
> @@ -555,6 +565,9 @@ static int ccs_data_parse_rules(struct bin_container *bin,
> bin_reserve(bin, sizeof(*rules) * num_rules);
> *__num_rules = num_rules;
> } else {
> + if (!rules_base)
> + return -EPROTO;
> +
> *__rules = rules_base;
> }
>
> @@ -690,7 +703,7 @@ static int ccs_data_parse_pdaf(struct bin_container *bin, struct ccs_pdaf_pix_lo
> }
>
> for (i = 0; i < max_block_type_id; i++) {
> - struct ccs_pdaf_pix_loc_pixel_desc_group *pdgroup;
> + struct ccs_pdaf_pix_loc_pixel_desc_group *pdgroup = NULL;
> unsigned int j;
>
> if (!is_contained(__num_pixel_descs, endp))
> @@ -721,6 +734,9 @@ static int ccs_data_parse_pdaf(struct bin_container *bin, struct ccs_pdaf_pix_lo
> if (!bin->base)
> continue;
>
> + if (!pdgroup)
> + return -EPROTO;
> +
> pdesc = &pdgroup->descs[j];
> pdesc->pixel_type = __pixel_desc->pixel_type;
> pdesc->small_offset_x = __pixel_desc->small_offset_x;
>
