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        <span style="font-family:Arial;"><span style="font-family:Arial;">Hi, I recently followed a tutorial on fuzzing the dnsmasq with AFL (</span><span style="font-family:Arial;">https://klaus.hohenpoelz.de/dnsmasq-fuzzing-with-afl.html). I repeated the same process on the newest version of dnsmasq. It appears that --dhcp-option does not allow the coexistence of <em>vendor </em>and <em>encap</em>.</span></span> 
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        <span style="font-family:Arial;"><span style="font-family:Arial;">My reproducing of the segfault:</span></span> 
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        <span style="font-family:Arial;"><span style="font-family:Arial;"><img src="cid:5038d9b2$1$18137018364$Coremail$gongchen17$pku.edu.cn">This is caused by a union of <em>encap </em>and <em>vendor_class </em>in the struct <em>dhcp_opt</em>.<br>
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        <span style="font-family:Arial;"><span style="font-family:Arial;"><img src="cid:5929ae85$2$18137018364$Coremail$gongchen17$pku.edu.cn"></span></span> 
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        <span style="font-family:Arial;"><span style="font-family:Arial;">And code here overwrites the value of <em>u.vendor_class</em> with <em>u.encap</em>.</span></span> 
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        <img src="cid:46b37e9b$3$18137018364$Coremail$gongchen17$pku.edu.cn"> 
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        <span style="font-family:Arial;"><span style="font-family:Arial;"><br>
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        <span style="font-family:Arial;"><span style="font-family:Arial;">Thanks a lot for your patience!</span></span> 
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        <span style="font-family:Arial;"><span style="font-family:Arial;"><br>
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        <span style="font-family:Arial;"><span style="font-family:Arial;">Best,</span></span> 
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        <span style="font-family:Arial;"><span style="font-family:Arial;">Chen</span></span> 
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        <span style="font-family:Arial;"><span style="font-family:Arial;"></span><span style="font-family:Arial;"></span></span> 
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