linux-kernel - Re: [PATCH v8 03/13] perf evlist: implement control command handling functions

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 23 Jun 2020 16:56:01 +0200
From:   Jiri Olsa <jolsa@...hat.com>
To:     Alexey Budankov <alexey.budankov@...ux.intel.com>
Cc:     Arnaldo Carvalho de Melo <acme@...nel.org>,
        Namhyung Kim <namhyung@...nel.org>,
        Alexander Shishkin <alexander.shishkin@...ux.intel.com>,
        Peter Zijlstra <peterz@...radead.org>,
        Ingo Molnar <mingo@...hat.com>,
        Andi Kleen <ak@...ux.intel.com>,
        linux-kernel <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v8 03/13] perf evlist: implement control command handling
 functions

On Wed, Jun 17, 2020 at 11:36:46AM +0300, Alexey Budankov wrote:

SNIP

> +	memset(cmd_data, 0, data_size--);
> +
> +	do {
> +		err = read(evlist->ctl_fd.fd, &c, 1);
> +		if (err > 0) {
> +			if (c == '\n' || c == '\0')
> +				break;
> +			cmd_data[bytes_read++] = c;
> +			if (bytes_read == data_size)
> +				break;
> +		} else {
> +			if (err == -1)
> +				pr_err("Failed to read from ctlfd %d: %m\n", evlist->ctl_fd.fd);
> +			break;
> +		}
> +	} while (1);
> +
> +	pr_debug("Message from ctl_fd: \"%s%s\"\n", cmd_data,
> +		 bytes_read == data_size ? "" : c == '\n' ? "\\n" : "\\0");
> +
> +	if (err > 0) {
> +		if (!strncmp(cmd_data, EVLIST_CTL_CMD_ENABLE_TAG,
> +			     strlen(EVLIST_CTL_CMD_ENABLE_TAG))) {

you could use sizeof(EVLIST_CTL_CMD_ENABLE_TAG) instead, no function call

> +			*cmd = EVLIST_CTL_CMD_ENABLE;
> +		} else if (!strncmp(cmd_data, EVLIST_CTL_CMD_DISABLE_TAG,
> +				    strlen(EVLIST_CTL_CMD_DISABLE_TAG))) {

ditto

jirka