From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Gustavo A. R. Silva" Subject: [PATCH][next] cgroup: Avoid -Wstringop-overflow warnings Date: Wed, 14 Jun 2023 19:18:22 -0600 Message-ID: Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1686791845; bh=jC/V/5wTuDMjSNiSOnA5excD/Pg4jzWuQwRXLi7lZ5Q=; h=Date:From:To:Cc:Subject:From; b=LNn3r6SsDlIceMsugdzXzyHk9WrMjwzuxupyyplrVHyioNpMJdpql/gLeE+cky74M 7/gIN433a9Az+BryjDhdebV9l6Mnw4rB9+iqI6K5ce3PdjuOyjyiwgS3o4L1jcdmQY t9PY3TpynCOtMjyn4mXp6Wga7IIu/2AZoBsp29aMD6JYTeKrrQppEc0MFMTKtgNwMF krwRXUZxh2Vchb79SSKMEvvLrj7xm3Q1Tb5PktEXXLDaadwmoVq5AWvQv4qwKOV4hQ Rs0JFIB02Mjw2n30gUblEh4OxBCw19+eCBmlKcuJ9iIvOLsYjFdW3V8a5voebM/9Ed mRzHWmC4lfCxA== Content-Disposition: inline List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Tejun Heo , Zefan Li , Johannes Weiner Cc: cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" , linux-hardening@vger.kernel.org Address the following -Wstringop-overflow warnings seen when built with ARM architecture and aspeed_g4_defconfig configuration (notice that under this configuration CGROUP_SUBSYS_COUNT == 0): kernel/cgroup/cgroup.c:1208:16: warning: 'find_existing_css_set' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=] kernel/cgroup/cgroup.c:1258:15: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=] kernel/cgroup/cgroup.c:6089:18: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=] kernel/cgroup/cgroup.c:6153:18: warning: 'css_set_hash' accessing 4 bytes in a region of size 0 [-Wstringop-overflow=] These changes are based on commit d20d30ebb199 ("cgroup: Avoid compiler warnings with no subsystems"). Signed-off-by: Gustavo A. R. Silva --- kernel/cgroup/cgroup.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index cd497b90e11a..1ee76e62eb98 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -1200,6 +1200,9 @@ static struct css_set *find_css_set(struct css_set *old_cset, unsigned long key; int ssid; + if (!CGROUP_HAS_SUBSYS_CONFIG) + return NULL; + lockdep_assert_held(&cgroup_mutex); /* First see if we already have a cgroup group that matches @@ -6045,6 +6048,9 @@ int __init cgroup_init(void) struct cgroup_subsys *ss; int ssid; + if (!CGROUP_HAS_SUBSYS_CONFIG) + return -EINVAL; + BUILD_BUG_ON(CGROUP_SUBSYS_COUNT > 16); BUG_ON(cgroup_init_cftypes(NULL, cgroup_base_files)); BUG_ON(cgroup_init_cftypes(NULL, cgroup_psi_files)); -- 2.34.1