linux-kernel - Re: [PATCH 19/22] perf tools: Add filename__read

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]

Message-ID: <1385135039.1747.118.camel@leonhard>
Date:	Sat, 23 Nov 2013 00:43:59 +0900
From:	Namhyung Kim <namhyung@...nel.org>
To:	Jiri Olsa <jolsa@...hat.com>
Cc:	linux-kernel@...r.kernel.org,
	Corey Ashford <cjashfor@...ux.vnet.ibm.com>,
	Frederic Weisbecker <fweisbec@...il.com>,
	Ingo Molnar <mingo@...e.hu>, Paul Mackerras <paulus@...ba.org>,
	Peter Zijlstra <a.p.zijlstra@...llo.nl>,
	Arnaldo Carvalho de Melo <acme@...hat.com>,
	Steven Rostedt <rostedt@...dmis.org>,
	David Ahern <dsahern@...il.com>
Subject: Re: [PATCH 19/22] perf tools: Add filename__read_str util function

2013-11-21 (목), 12:01 +0100, Jiri Olsa:
> Adding filename__read_str util function to read
> text file and return it in the char array.
> 
> The interface is:
>   int filename__read_str(const char *filename, char **buf, size_t *sizep)
> 
>   Returns 0/-1 if the read suceeded/fail respectively.
> 
>   buf  - place to store the data pointer
>   size - place to store data size

[SNIP]
> +int filename__read_str(const char *filename, char **buf, size_t *sizep)
> +{
> +	size_t size = 0, alloc_size = 0;
> +	void *bf = NULL, *nbf;
> +	int fd, n, err = 0;
> +
> +	fd = open(filename, O_RDONLY);
> +	if (fd < 0)
> +		return -errno;
> +
> +	do {
> +		if (size == alloc_size) {
> +			alloc_size += BUFSIZ;
> +			nbf = realloc(bf, alloc_size);
> +			if (!nbf) {
> +				err = -ENOMEM;
> +				break;
> +			}
> +
> +			bf = nbf;
> +		}
> +
> +		n = read(fd, bf + size, BUFSIZ);

Shouldn't it be "read(fd, bf + size, alloc_size - size)"?
Otherwise there might be a problem if read() returned early for some
reason with small size and then retry with a full BUFSIZ..


> +		if (n < 0) {
> +			err = 0;

I think it needs to check the size also since read() might fail at the
first invocation.  What about this?

		if (n < 0) {
			if (size)
				err = 0;
			else
				err = -errno;

Thanks,
Namhyung

> +			break;
> +		}
> +
> +		size += n;
> +	} while (n > 0);
> +
> +	if (!err) {
> +		*sizep = size;
> +		*buf   = bf;
> +	} else
> +		free(bf);
> +
> +	close(fd);
> +	return err;
> +}



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/