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This is an automatically generated e-mail. To reply, visit:
<a href="https://git.reviewboard.kde.org/r/129259/">https://git.reviewboard.kde.org/r/129259/</a>
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<a href="https://git.reviewboard.kde.org/r/129259/diff/2/?file=482957#file482957line790" style="color: black; font-weight: bold; text-decoration: underline;">src/ioslaves/file/file.cpp</a>
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(Diff revision 2)
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<th bgcolor="#e9eaa8" style="border-right: 1px solid #C0C0C0;" align="right"><font size="2">790</font></th>
<td bgcolor="#fdfebc" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "> <span class="n"><span class="hl">linkTargetB</span>uffer</span><span class="p"><span class="hl">.</span></span><span class="n"><span class="hl">res</span>ize</span><span class="p">(</span><span class="n">buff</span><span class="p">.</span><span class="n">st_size</span><span class="p"><span class="hl">)</span>;</span></pre></td>
<th bgcolor="#e9eaa8" style="border-left: 1px solid #C0C0C0; border-right: 1px solid #C0C0C0;" align="right"><font size="2">790</font></th>
<td bgcolor="#fdfebc" width="50%"><pre style="font-size: 8pt; line-height: 140%; margin: 0; "> <span class="kt"><span class="hl">size_t</span></span><span class="hl"> </span><span class="n"><span class="hl">b</span>uffer<span class="hl">S</span>ize</span><span class="hl"> </span><span class="o"><span class="hl">=</span></span><span class="hl"> </span><span class="p">(</span><span class="n">buff</span><span class="p">.</span><span class="n">st_size</span><span class="hl"> </span><span class="o"><span class="hl">==</span></span><span class="hl"> </span><span class="mi"><span class="hl">0</span></span><span class="p"><span class="hl">)</span></span><span class="hl"> </span><span class="o"><span class="hl">?</span></span><span class="hl"> </span><span class="mi"><span class="hl">1024</span></span><span class="hl"> </span><span class="o"><span class="hl">:</span></span><span class="hl"> </span><span class="n"><span class="hl">buff</span></span><span class="p"><span class="hl">.</span></span><span class="n"><span class="hl">st_size</span></span><span class="hl"> </span><span class="p">;</span></pre></td>
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<pre style="white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;"><p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">I don't think we should use buff.st_size at all. We now know that on "virtual" filesystems, the link's reported size is basically useless for this purpose. In the case I reported in the bug, we are allocating 2 GiB just to read a measly file path.</p>
<p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">We should just always start with a small constant (maybe 1024 is fine), and then increase as necessary.</p></pre>
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<p>- Jonathan Doman</p>
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<p>On October 25th, 2016, 9:51 a.m. CDT, taro yamada wrote:</p>
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<div>Review request for KDE Frameworks.</div>
<div>By taro yamada.</div>
<p style="color: grey;"><i>Updated Oct. 25, 2016, 9:51 a.m.</i></p>
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<b style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Bugs: </b>
<a href="https://bugs.kde.org/show_bug.cgi?id=369275">369275</a>
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<b style="color: #575012; font-size: 10pt;">Repository: </b>
kio
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Description </h1>
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<pre style="margin: 0; padding: 0; white-space: pre-wrap; white-space: -moz-pre-wrap; white-space: -pre-wrap; white-space: -o-pre-wrap; word-wrap: break-word;"><p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">Currently, KIO uses lstat to get the buffersize for readlink.
But in certain situations, it returns inappropriate value.</p>
<p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">For example, "/proc/self" or "/sys/bus/cpu/devices/*" returns its size is 0 , and then readlink fails with EINVAL.(so link won't be shown in kde application.)
TMSU seems it returns its target's actual filesize insted of the link's filesize itself.</p>
<p style="padding: 0;text-rendering: inherit;margin: 0;line-height: inherit;white-space: inherit;">This patch changes the buffersize to 1024 bytes if it is 0.
And later truncate it to actual size.</p></pre>
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<h1 style="color: #575012; font-size: 10pt; margin-top: 1.5em;">Diffs</b> </h1>
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<li>src/ioslaves/file/file.cpp <span style="color: grey">(8b17d31)</span></li>
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<p><a href="https://git.reviewboard.kde.org/r/129259/diff/" style="margin-left: 3em;">View Diff</a></p>
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