Message-ID: <4B258F0A.3030903@cn.fujitsu.com>
Date: Mon, 14 Dec 2009 09:04:10 +0800
From: Li Zefan <lizf@cn.fujitsu.com>
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To: Frederic Weisbecker <fweisbec@gmail.com>
CC: Steven Rostedt <rostedt@goodmis.org>,
       Frederic Riss <frederic.riss@gmail.com>, Ingo Molnar <mingo@elte.hu>,
       Wenji Huang <wenji.huang@oracle.com>,
       LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 1/4] ftrace: Fix MATCH_END_ONLY filter matching
References: <4B2217D0.5000308@cn.fujitsu.com> <87d3b2040912110420w270cff7ew36a7f2389a88fdb9@mail.gmail.com> <20091211122721.GH5244@nowhere> <1260544231.2146.360.camel@gandalf.stny.rr.com> <20091211174632.GC5094@nowhere>
In-Reply-To: <20091211174632.GC5094@nowhere>
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>>>>> For '*foo' pattern, we should allow any string ending with
>>>>> 'foo', but ftrace filter incorrectly disallows strings
>>>>> like bar_foo_foo:
>>>> [...]
>>>>>        case MATCH_END_ONLY:
>>>>> -               ptr = strstr(str, regex);
>>>>> -               if (ptr && (ptr[len] == 0))
>>>>> +               slen = strlen(str);
>>>>> +               if (slen >= len && memcpy(str + slen - len, regex, len))
>>>>>                        matched = 1;
>>>> Shouldn't that be memcmp() == 0? I don't see how memcpy might serve as
>>>> a compare operator.
>>>>
>>>> Fred.
>>>
>>> Oh you're right, I reviewed it too quickly. Perhaps the star's
>>> alignment made it possible for only one Frederic to review it
>>> the right way...
>>>
>> The stars are still fuzzy to me. How does memcpy work here?
> 
> 
> It doesn't, I guess Li intended to use memcmp.
> 

Oops, I forgot to fix this before sending the patch out.. :(

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