linux-kernel - Re: [PATCH] kprobes: be more permissive when user specifies both symbol name and address

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: <CAHz2CGV_WA_bMwYCg1QCyFpCv0PKgPhBQUf_pFQbNn-guLL+Ag@mail.gmail.com>
Date:	Tue, 15 Apr 2014 16:11:14 +0800
From:	Zhan Jianyu <nasa4836@...il.com>
To:	Masami Hiramatsu <masami.hiramatsu.pt@...achi.com>
Cc:	ananth@...ibm.com, anil.s.keshavamurthy@...el.com,
	davem@...emloft.net, rdunlap@...radead.org,
	linux-doc@...r.kernel.org, LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] kprobes: be more permissive when user specifies both
 symbol name and address

On Mon, Apr 14, 2014 at 11:00 PM, Masami Hiramatsu
<masami.hiramatsu.pt@...achi.com> wrote:
> if (p->addr) {
>   if (p->symbol) {
>     sym = kallsyms_lookup(p->addr, ... &offs ...);
>     if (strcmp(sym,p->symbol) != 0 || offs != p->offset) {
>       pr_warning("Error! ...");
>       goto fail;
>     }
>   }
> } else if (p->symbol) {
>   kprobe_lookup_name(p->symbol_name, addr);
>   if (!addr)
>     goto fail;
> } else
>   goto fail;


Hmm, let's clasify all conditions.

1. Only symbol, check it, if not found, fail.
2. Only address, check it, if not found, fail.
3. Both, check address,
    3.1 not found, fail, because some symbols might have muplitple instances,
          we don't bother to check symbol name.
    3.2 found, check if symbol mismatch, if yes, fail.


Is this reasonable?  Next mail is a renewed patch following this priciple.


Regards,
Jianyu Zhan
--
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/