From: Jeff King <peff@peff.net>
To: "René Scharfe" <l.s.r@web.de>
Cc: Git List <git@vger.kernel.org>, Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCH] tag: avoid NULL pointer arithmetic
Date: Mon, 2 Oct 2017 15:23:27 -0400 [thread overview]
Message-ID: <20171002192327.xyynkh47r2kgir7f@sigill.intra.peff.net> (raw)
In-Reply-To: <32a8b949-638a-1784-7fba-948ae32206fc@web.de>
On Mon, Oct 02, 2017 at 03:06:57PM +0200, René Scharfe wrote:
> >> Avoid the ASan error by casting the results of the lookup functions to
> >> struct object pointers. That works fine with NULL pointers as well. We
> >> already rely on the object member being first in all object types in
> >> other places in the code.
> >
> > Out of curiosity, did you have to do anything to coax this out of ASan
> > (e.g., a specific version)? I've been running it pretty regularly and
> > didn't see this one (I did switch from clang to gcc a month or two ago,
> > but this code is pretty old, I think).
>
> I did "make -j4 SANITIZE=undefined,address BLK_SHA1=1 test" with
> clang version 4.0.1-1 (tags/RELEASE_401/final), and t1450-fsck.sh failed.
Interesting. I can trigger it with the same setup, but not if:
1. I use gcc instead of clang.
2. If I only use one of UBSan and ASan. It's the combination that
triggers it.
-Peff
next prev parent reply other threads:[~2017-10-02 19:23 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-10-01 14:45 [PATCH] tag: avoid NULL pointer arithmetic René Scharfe
2017-10-02 4:13 ` Junio C Hamano
2017-10-02 5:08 ` Jeff King
2017-10-02 13:06 ` René Scharfe
2017-10-02 19:23 ` Jeff King [this message]
2017-10-03 10:22 ` SZEDER Gábor
2017-10-03 12:51 ` René Scharfe
2017-10-03 13:47 ` [PATCH] fsck: check results of lookup_blob() and lookup_tree() for NULL René Scharfe
2017-10-04 4:00 ` Junio C Hamano
2017-10-05 19:41 ` René Scharfe
2017-10-05 19:41 ` [PATCH v2] fsck: handle NULL return of lookup_blob() and lookup_tree() René Scharfe
2017-10-06 2:23 ` Junio C Hamano
2017-10-06 16:21 ` René Scharfe
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
List information: http://vger.kernel.org/majordomo-info.html
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20171002192327.xyynkh47r2kgir7f@sigill.intra.peff.net \
--to=peff@peff.net \
--cc=git@vger.kernel.org \
--cc=gitster@pobox.com \
--cc=l.s.r@web.de \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
Code repositories for project(s) associated with this public inbox
https://80x24.org/mirrors/git.git
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).