[FS#994] dnsmasq repeatedly crashes due to invalid write access

[LEDE Bugs]

The following task has a new comment added:

FS#994 - dnsmasq repeatedly crashes due to invalid write access
User who did this - Marcin Jurkowski (marcin1j)

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Then it's yet another issue. In my case return address is src/rfc1035.c:1231, not src/rfc1035.c:1228 and the problem still exists in release 10:


[24765.577349] do_page_fault(): sending SIGSEGV to dnsmasq for invalid write access to 00a3f000
[24765.594344] epc = 77bedec0 in libc.so[77b7b000+92000]
[24765.604458] ra  = 00406e05 in dnsmasq[400000+21000]
[24769.206101] do_page_fault(): sending SIGSEGV to dnsmasq for invalid write access to 0088e000
[24769.223124] epc = 779b9ec0 in libc.so[77947000+92000]
[24769.233240] ra  = 00406e05 in dnsmasq[400000+21000]
[24896.049121] do_page_fault(): sending SIGSEGV to dnsmasq for invalid write access to 006f4000
[24896.066035] epc = 77d50eb8 in libc.so[77cde000+92000]
[24896.076129] ra  = 00406e05 in dnsmasq[400000+21000]
[25012.530166] do_page_fault(): sending SIGSEGV to dnsmasq for invalid write access to 00b07000
[25012.547072] epc = 77435ed0 in libc.so[773c3000+92000]
[25012.557170] ra  = 00406e05 in dnsmasq[400000+21000]
[25213.195928] do_page_fault(): sending SIGSEGV to dnsmasq for invalid write access to 006f9000
[25213.212813] epc = 779c0ec0 in libc.so[7794e000+92000]
[25213.222940] ra  = 00406e05 in dnsmasq[400000+21000]
[25217.511738] do_page_fault(): sending SIGSEGV to dnsmasq for invalid write access to 00b06000
[25217.528643] epc = 770c2ec0 in libc.so[77050000+92000]
[25217.538749] ra  = 00406e05 in dnsmasq[400000+21000]
[25351.294752] do_page_fault(): sending SIGSEGV to dnsmasq for invalid write access to 00a00000
[25351.311763] epc = 77f52ed0 in libc.so[77ee0000+92000]
[25351.321881] ra  = 00406e05 in dnsmasq[400000+21000]
[25357.126580] do_page_fault(): sending SIGSEGV to dnsmasq for invalid write access to 00beb000
[25357.143485] epc = 7784cec0 in libc.so[777da000+92000]
[25357.153585] ra  = 00406e05 in dnsmasq[400000+21000]
[25573.914415] do_page_fault(): sending SIGSEGV to dnsmasq for invalid write access to 00930000
[25573.931322] epc = 775f9ec0 in libc.so[77587000+92000]
[25573.941423] ra  = 00406e05 in dnsmasq[400000+21000]
[25577.487255] do_page_fault(): sending SIGSEGV to dnsmasq for invalid write access to 00a3c000
[25577.504169] epc = 7753fed0 in libc.so[774cd000+92000]
[25577.514282] ra  = 00406e05 in dnsmasq[400000+21000]


Unfortunately I don't know how to reproduce it. I'll try to comment out memset and see if it helps.
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More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=994#comment3408