https://jira.whamcloud.com This file is an XML representation of an issue en-us 9.4.14 940014 05-12-2023 https://jira.whamcloud.com/browse/LU-16510 Lustre <p>The fortified memcpy() from kernel v5.11-11104-ga28a6e860c6c through v5.18-rc5-1405-g43213daed6d6 incorrectly reports a false positive.</p> <div class="preformatted panel" style="border-width: 1px;"><div class="preformattedContent panelContent"> <pre> 13:54:25 In function 'memcpy', 13:54:25 inlined from 'lov_iocontrol' at /tmp/rpmbuild-lustre-jenkins-4fGYbbr1/BUILD/lustre-2.15.53_116_g5d22f15/lustre/lov/lov_obd.c:1057:4: 13:54:25 include/linux/fortify-string.h:187:25: error: call to '__read_overflow2' declared with attribute error: detected read beyond size of object passed as 2nd parameter 13:54:25 187 | __read_overflow2(); 13:54:25 | ^~~~~~~~~~~~~~~~~~ </pre> </div></div> LU-16510

Provide an interim 'good' fortified memcpy from 6.1

Bug Minor Resolved Fixed Patrick Farrell Shaun Tancheff Sun, 29 Jan 2023 13:47:22 +0000 Thu, 14 Sep 2023 14:05:51 +0000 Thu, 14 Sep 2023 14:05:51 +0000 Lustre 2.16.0 Lustre 2.15.3 0 4 <p>"Shaun Tancheff &lt;shaun.tancheff@hpe.com&gt;" uploaded a new patch: <a href="https://review.whamcloud.com/c/fs/lustre-release/+/49811" class="external-link" target="_blank" rel="nofollow noopener">https://review.whamcloud.com/c/fs/lustre-release/+/49811</a><br/> Subject: <a href="https://jira.whamcloud.com/browse/LU-16510" title="Provide an interim &#39;good&#39; fortified memcpy from 6.1" class="issue-link" data-issue-key="LU-16510"><del>LU-16510</del></a> build: fortified memcpy from linux 6.1<br/> Project: fs/lustre-release<br/> Branch: master<br/> Current Patch Set: 1<br/> Commit: e4b87269f249f94c004ffb3d7ed6c4b369956fcf</p> <p>"Jian Yu &lt;yujian@whamcloud.com&gt;" uploaded a new patch: <a href="https://review.whamcloud.com/c/fs/lustre-release/+/49815" class="external-link" target="_blank" rel="nofollow noopener">https://review.whamcloud.com/c/fs/lustre-release/+/49815</a><br/> Subject: <a href="https://jira.whamcloud.com/browse/LU-16510" title="Provide an interim &#39;good&#39; fortified memcpy from 6.1" class="issue-link" data-issue-key="LU-16510"><del>LU-16510</del></a> build: fortified memcpy from linux 6.1<br/> Project: fs/lustre-release<br/> Branch: b2_15<br/> Current Patch Set: 1<br/> Commit: 0217d59249441102d6d4d51e6ec8d87d339d5e8c</p> <p>"Oleg Drokin &lt;green@whamcloud.com&gt;" merged in patch <a href="https://review.whamcloud.com/c/fs/lustre-release/+/49811/" class="external-link" target="_blank" rel="nofollow noopener">https://review.whamcloud.com/c/fs/lustre-release/+/49811/</a><br/> Subject: <a href="https://jira.whamcloud.com/browse/LU-16510" title="Provide an interim &#39;good&#39; fortified memcpy from 6.1" class="issue-link" data-issue-key="LU-16510"><del>LU-16510</del></a> build: fortified memcpy from linux 6.1<br/> Project: fs/lustre-release<br/> Branch: master<br/> Current Patch Set: <br/> Commit: 919b93b951d4a9aa0400b9c882a1f68b79d8f118</p> <p>Landed for 2.16</p> <p>"Oleg Drokin &lt;green@whamcloud.com&gt;" merged in patch <a href="https://review.whamcloud.com/c/fs/lustre-release/+/49815/" class="external-link" target="_blank" rel="nofollow noopener">https://review.whamcloud.com/c/fs/lustre-release/+/49815/</a><br/> Subject: <a href="https://jira.whamcloud.com/browse/LU-16510" title="Provide an interim &#39;good&#39; fortified memcpy from 6.1" class="issue-link" data-issue-key="LU-16510"><del>LU-16510</del></a> build: fortified memcpy from linux 6.1<br/> Project: fs/lustre-release<br/> Branch: b2_15<br/> Current Patch Set: <br/> Commit: 83658e38cd497c777a3056edebc8cd34803b45f8</p> <p><a href="https://jira.whamcloud.com/secure/ViewProfile.jspa?name=adegremont_nvda" class="user-hover" rel="adegremont_nvda">adegremont_nvda</a> pointed out this patch is missing a key component.  Quoting him:</p> <p>"</p> <p><a href="https://jira.whamcloud.com/browse/LU-16510" title="Provide an interim &#39;good&#39; fortified memcpy from 6.1" class="issue-link" data-issue-key="LU-16510"><del>LU-16510</del></a> has a defect. The fortify.h file is missing one important bit compared to the upstream file it copied:</p> <div class="code panel" style="border-width: 1px;"><div class="codeContent panelContent"> <pre class="code-java"> +/** + * unsafe_memcpy - memcpy implementation with no FORTIFY bounds checking + * + * @dst: Destination memory address to write to + * @src: Source memory address to read from + * @bytes: How many bytes to write to @dst from @src + * @justification: Free-form text or comment describing why the use is needed + * + * This should be used <span class="code-keyword">for</span> corner cases where the compiler cannot <span class="code-keyword">do</span> the + * right thing, or during transitions between APIs, etc. It should be used + * very rarely, and includes a place <span class="code-keyword">for</span> justification detailing where bounds + * checking has happened, and why existing solutions cannot be employed. + */ +#define unsafe_memcpy(dst, src, bytes, justification)          \ +       __underlying_memcpy(dst, src, bytes) +</pre> </div></div> <p>"</p> <p>I'll push a patch.</p> <p>"Patrick Farrell &lt;pfarrell@whamcloud.com&gt;" uploaded a new patch: <a href="https://review.whamcloud.com/c/fs/lustre-release/+/50573" class="external-link" target="_blank" rel="nofollow noopener">https://review.whamcloud.com/c/fs/lustre-release/+/50573</a><br/> Subject: <a href="https://jira.whamcloud.com/browse/LU-16510" title="Provide an interim &#39;good&#39; fortified memcpy from 6.1" class="issue-link" data-issue-key="LU-16510"><del>LU-16510</del></a> build: include unsafe_memcpy definition<br/> Project: fs/lustre-release<br/> Branch: master<br/> Current Patch Set: 1<br/> Commit: 991db242d198ab56d354cd374bf8606fa312fd65</p> <p>"Oleg Drokin &lt;green@whamcloud.com&gt;" merged in patch <a href="https://review.whamcloud.com/c/fs/lustre-release/+/50573/" class="external-link" target="_blank" rel="nofollow noopener">https://review.whamcloud.com/c/fs/lustre-release/+/50573/</a><br/> Subject: <a href="https://jira.whamcloud.com/browse/LU-16510" title="Provide an interim &#39;good&#39; fortified memcpy from 6.1" class="issue-link" data-issue-key="LU-16510"><del>LU-16510</del></a> build: include unsafe_memcpy definition<br/> Project: fs/lustre-release<br/> Branch: master<br/> Current Patch Set: <br/> Commit: 565b21bf65e385a9b4fd8ee31cabe7892345b783</p> <p>"Jian Yu &lt;yujian@whamcloud.com&gt;" uploaded a new patch: <a href="https://review.whamcloud.com/c/fs/lustre-release/+/50667" class="external-link" target="_blank" rel="nofollow noopener">https://review.whamcloud.com/c/fs/lustre-release/+/50667</a><br/> Subject: <a href="https://jira.whamcloud.com/browse/LU-16510" title="Provide an interim &#39;good&#39; fortified memcpy from 6.1" class="issue-link" data-issue-key="LU-16510"><del>LU-16510</del></a> build: include unsafe_memcpy definition<br/> Project: fs/lustre-release<br/> Branch: b2_15<br/> Current Patch Set: 1<br/> Commit: 379a6b3d4696e28b1db6a5bfd0d6f92fbe6378de</p> <p>Landed for 2.16</p> <p>"Oleg Drokin &lt;green@whamcloud.com&gt;" merged in patch <a href="https://review.whamcloud.com/c/fs/lustre-release/+/50667/" class="external-link" target="_blank" rel="nofollow noopener">https://review.whamcloud.com/c/fs/lustre-release/+/50667/</a><br/> Subject: <a href="https://jira.whamcloud.com/browse/LU-16510" title="Provide an interim &#39;good&#39; fortified memcpy from 6.1" class="issue-link" data-issue-key="LU-16510"><del>LU-16510</del></a> build: include unsafe_memcpy definition<br/> Project: fs/lustre-release<br/> Branch: b2_15<br/> Current Patch Set: <br/> Commit: 8f4004809461bb2cab20c72d20980edf32c98793</p> <p>"Jian Yu &lt;yujian@whamcloud.com&gt;" uploaded a new patch: <a href="https://review.whamcloud.com/c/fs/lustre-release/+/51973" class="external-link" target="_blank" rel="nofollow noopener">https://review.whamcloud.com/c/fs/lustre-release/+/51973</a><br/> Subject: <a href="https://jira.whamcloud.com/browse/LU-16510" title="Provide an interim &#39;good&#39; fortified memcpy from 6.1" class="issue-link" data-issue-key="LU-16510"><del>LU-16510</del></a> build: check if CONFIG_FORTIFY_SOURCE is defined<br/> Project: fs/lustre-release<br/> Branch: master<br/> Current Patch Set: 1<br/> Commit: 06956ef63fd7a0489648fe85c2f1e1904e78424e</p> <p>"Oleg Drokin &lt;green@whamcloud.com&gt;" merged in patch <a href="https://review.whamcloud.com/c/fs/lustre-release/+/51973/" class="external-link" target="_blank" rel="nofollow noopener">https://review.whamcloud.com/c/fs/lustre-release/+/51973/</a><br/> Subject: <a href="https://jira.whamcloud.com/browse/LU-16510" title="Provide an interim &#39;good&#39; fortified memcpy from 6.1" class="issue-link" data-issue-key="LU-16510"><del>LU-16510</del></a> build: check if CONFIG_FORTIFY_SOURCE is defined<br/> Project: fs/lustre-release<br/> Branch: master<br/> Current Patch Set: <br/> Commit: a52545afeda06441841f6143d8fd563251549acb</p> <p>Another bug has shown up. This time its the __QCTL_COPY macro in lustre_idl.h that fails to build.<br/> In function 'memcpy',<b>10:33:49</b> inlined from 'lov_iocontrol' at /tmp/rpmbuild-lustre-jenkins-MOxpnLlK/BUILD/lustre-2.15.58_1_g13e68ce/lustre/lov/lov_obd.c:1079:4:<b>10:33:49</b> include/linux/fortify-string.h:187:25: error: call to '__read_overflow2' declared with attribute error: detected read beyond size of object passed as 2nd parameter*10:33:49* 187 | __read_overflow2();<b>10:33:49</b> | ^~~~~~~~~~~~~~~~~~</p> <p>I looked into this bug and found the issue is that memcpy that is fortify doesn't work with flexible arrays like QCTL_COPY works with. The infrastructure to support this has landed in the newest kernels; but to support that with every kernel Lustre supports requires way too much back porting. So the solution is not blanket include linux-fortify-string.h since it will break things. Just include it where it is needed.  </p> Related Development Rank 1|i03baf: Rank (Obsolete) 9223372036854775807 Severity