From: Arjun Shankar via Libc-alpha <libc-alpha@sourceware.org>
To: Siddhesh Poyarekar <siddhesh@sourceware.org>
Cc: libc-alpha@sourceware.org
Subject: Re: [PATCH 2/5] gconv_parseconfdir: Fix memory leak
Date: Tue, 3 Aug 2021 15:09:34 +0000 [thread overview]
Message-ID: <20210803150934.GB6986@lostca.se> (raw)
In-Reply-To: <20210727174129.3612656-3-siddhesh@sourceware.org>
Hi Siddhesh,
> The allocated `conf` would leak if we have to skip over the file due
> to the underlying filesystem not supporting dt_type.
> ---
> iconv/gconv_parseconfdir.h | 9 ++++-----
> 1 file changed, 4 insertions(+), 5 deletions(-)
>
> diff --git a/iconv/gconv_parseconfdir.h b/iconv/gconv_parseconfdir.h
> index a4153e54c6..2f062689ec 100644
> --- a/iconv/gconv_parseconfdir.h
> +++ b/iconv/gconv_parseconfdir.h
> @@ -153,12 +153,11 @@ gconv_parseconfdir (const char *dir, size_t dir_len)
> struct stat64 st;
> if (asprintf (&conf, "%s/%s", buf, ent->d_name) < 0)
> continue;
> - if (ent->d_type == DT_UNKNOWN
> - && (lstat64 (conf, &st) == -1
> - || !S_ISREG (st.st_mode)))
> - continue;
>
> - found |= read_conf_file (conf, dir, dir_len);
> + if (ent->d_type != DT_UNKNOWN
> + || (lstat64 (conf, &st) != -1 && S_ISREG (st.st_mode)))
> + found |= read_conf_file (conf, dir, dir_len);
> +
> free (conf);
> }
> }
Reversed the condition to conditionally modify `found' first, then
unconditionally free `conf' afterward to avoid a leak. The change looks
correct to me.
I'm wondering if the new condition is harder to read than simply !ing the
old one. But I guess it's not that important compared to the fix itself.
Reviewed-by: Arjun Shankar <arjun@redhat.com>
Cheers!
next prev parent reply other threads:[~2021-08-03 15:09 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-07-27 17:41 [PATCH 0/5] Static analysis fixes Siddhesh Poyarekar via Libc-alpha
2021-07-27 17:41 ` [PATCH 1/5] ldconfig: avoid leak on empty paths in config file Siddhesh Poyarekar via Libc-alpha
2021-08-03 15:08 ` Arjun Shankar via Libc-alpha
2021-07-27 17:41 ` [PATCH 2/5] gconv_parseconfdir: Fix memory leak Siddhesh Poyarekar via Libc-alpha
2021-08-03 15:09 ` Arjun Shankar via Libc-alpha [this message]
2021-07-27 17:41 ` [PATCH 3/5] iconv_charmap: Close output file when done Siddhesh Poyarekar via Libc-alpha
2021-08-03 15:15 ` Arjun Shankar via Libc-alpha
2021-07-27 17:41 ` [PATCH 4/5] copy_and_spawn_sgid: Avoid double calls to close() Siddhesh Poyarekar via Libc-alpha
2021-08-03 15:25 ` Arjun Shankar via Libc-alpha
2021-07-27 17:41 ` [PATCH 5/5] gaiconf_init: Avoid double-free in label and precedence lists Siddhesh Poyarekar via Libc-alpha
2021-08-03 15:34 ` Arjun Shankar via Libc-alpha
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