From patchwork Tue Jan 5 12:49:14 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sakari Ailus X-Patchwork-Id: 357197 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 56399C433DB for ; Tue, 5 Jan 2021 12:58:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 185D022AAC for ; Tue, 5 Jan 2021 12:58:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727977AbhAEM6C (ORCPT ); Tue, 5 Jan 2021 07:58:02 -0500 Received: from retiisi.eu ([95.216.213.190]:57400 "EHLO hillosipuli.retiisi.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725932AbhAEM6B (ORCPT ); Tue, 5 Jan 2021 07:58:01 -0500 Received: from lanttu.localdomain (lanttu-e.localdomain [192.168.1.64]) by hillosipuli.retiisi.eu (Postfix) with ESMTP id 17DAB634C87; Tue, 5 Jan 2021 14:56:01 +0200 (EET) From: Sakari Ailus To: linux-media@vger.kernel.org Cc: Hans Verkuil Subject: [PATCH 1/1] ccs: Make (non-)use of uninitialised variables more robust Date: Tue, 5 Jan 2021 14:49:14 +0200 Message-Id: <20210105124914.22900-1-sakari.ailus@linux.intel.com> X-Mailer: git-send-email 2.29.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org 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 Signed-off-by: Sakari Ailus Acked-by: Hans Verkuil --- 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;