From: Junio C Hamano <gitster@pobox.com>
To: Heiko Voigt <hvoigt@hvoigt.net>
Cc: git@vger.kernel.org, "Thomas Rast" <trast@student.ethz.ch>,
"Torsten Bögershausen" <tboegi@web.de>
Subject: Re: [PATCH] link_alt_odb_entry: fix read over array bounds reported by valgrind
Date: Sun, 29 Jul 2012 17:54:02 -0700 [thread overview]
Message-ID: <7v4noqul05.fsf@alter.siamese.dyndns.org> (raw)
In-Reply-To: <20120728154635.GB98893@book.hvoigt.net> (Heiko Voigt's message of "Sat, 28 Jul 2012 17:46:36 +0200")
Heiko Voigt <hvoigt@hvoigt.net> writes:
> pfxlen can be longer than the path in objdir when relative_base contains
> the path to gits object directory.
s/gits/????/ perhaps "Git's", but I am not sure.
> Signed-off-by: Heiko Voigt <hvoigt@hvoigt.net>
> ---
> sha1_file.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/sha1_file.c b/sha1_file.c
> index 4ccaf7a..631d0dd 100644
> --- a/sha1_file.c
> +++ b/sha1_file.c
> @@ -251,7 +251,7 @@ static int link_alt_odb_entry(const char * entry, int len, const char * relative
> const char *objdir = get_object_directory();
> struct alternate_object_database *ent;
> struct alternate_object_database *alt;
> - int pfxlen, entlen;
> + int pfxlen, entlen, objdirlen;
> struct strbuf pathbuf = STRBUF_INIT;
>
> if (!is_absolute_path(entry) && relative_base) {
> @@ -298,7 +298,8 @@ static int link_alt_odb_entry(const char * entry, int len, const char * relative
> return -1;
> }
> }
> - if (!memcmp(ent->base, objdir, pfxlen)) {
> + objdirlen = strlen(objdir);
> + if (!memcmp(ent->base, objdir, pfxlen > objdirlen ? objdirlen : pfxlen)) {
The new code tells us to compare up to the shorter length between
objdir (i.e. path/to/.git/objects) and the given alternate object
directory (i.e. alt/path/to/.git/objects), but is that really what
we want? What happens if the given alternate object directory were
"path/to/.git/objects-not-quite", with objdir "path/to/.git/objects"?
They are not the same directory, and this check is about avoiding
"the common mistake of listing ... object directory itself", no?
> free(ent);
> return -1;
> }
next prev parent reply other threads:[~2012-07-30 0:54 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-07-28 15:46 [PATCH] link_alt_odb_entry: fix read over array bounds reported by valgrind Heiko Voigt
2012-07-30 0:54 ` Junio C Hamano [this message]
2012-07-30 1:01 ` Junio C Hamano
2012-07-30 17:33 ` [PATCH v2] " Heiko Voigt
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