From: Paul Semel <semelpaul@gmail.com>
To: xen-devel@lists.xenproject.org
Cc: wei.liu2@citrix.com
Subject: [xen-devel] [fuzz] [x86 emulator] Input size
Date: Thu, 22 Feb 2018 13:39:01 +0100 [thread overview]
Message-ID: <a1290a06-2396-f9ca-16b5-c6571a0103a7@gmail.com> (raw)
Hello,
In the x86 instruction emulator fuzzer, when checking wether the input size is
correct, we are checking for this bounds : DATA_OFFSET < size < INPUT_SIZE.
The fact is that INPUT_SIZE is actually the size of the data buffer in the
fuzz_corpus structure. This way, AFL is not able to have full control over this
entry, as we are actually filling this buffer for at most
INPUT_SIZE - DATA_OFFSET.
If I understand the fuzzer correctly, we really need to give full control on
this to AFL so that we can get some "random" from it.
I am wondering if the bounds should rather be :
DATA_OFFSET < size < sizeof (struct fuzz_corpus)
but maybe I am missing something here 🙂
Thanks,
--
Paul Semel
_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel
next reply other threads:[~2018-02-22 12:16 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-02-22 12:39 Paul Semel [this message]
2018-02-22 18:00 ` [xen-devel] [fuzz] [x86 emulator] Input size Wei Liu
2018-02-22 23:57 ` [PATCH] fuzz/x86_emulate: fix bounds for input size Paul Semel
2018-02-23 8:20 ` Paul Semel
2018-02-23 10:44 ` George Dunlap
2018-02-23 12:07 ` Paul Semel
2018-02-23 16:30 ` Wei Liu
2018-02-23 16:33 ` George Dunlap
2018-02-23 16:37 ` Wei Liu
2018-02-23 22:41 ` Paul Semel
2018-02-23 22:48 ` [PATCH v2] " Paul Semel
2018-02-26 10:33 ` Wei Liu
2018-03-02 12:30 ` Wei Liu
2018-02-27 10:39 ` George Dunlap
2018-02-28 17:30 ` Paul Semel
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
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=a1290a06-2396-f9ca-16b5-c6571a0103a7@gmail.com \
--to=semelpaul@gmail.com \
--cc=wei.liu2@citrix.com \
--cc=xen-devel@lists.xenproject.org \
/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.
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 NNTP newsgroup(s).