[Dnsmasq-discuss] [PATCH] Fix double free() corruption due to config

Dominik Derigs dl6er at dl6er.de
Mon Jun 17 15:43:03 UTC 2024


Hey Simon,

the attached patch fixes a double free() corruption leading to a crash 
during startup of dnsmasq. The crash can be reproduced by using a 
rev-server addresses with a prefix length != {8,16,24,32}, e.g.

rev-server=192.168.0.0/25,home.mydomain.com

The crash is caused by freeing too early (within the loop). The crash 
does not happen for prefix lengths {8,16,24,32} as the loop runs only 
once. However, for other prefixes, the loop runs more often (e.g. 128x 
for /25 networks as above).

Best,
Dominik
-------------- next part --------------
A non-text attachment was scrubbed...
Name: 0001-Fix-crash-caused-by-double-free-corruption-encounter.patch
Type: text/x-patch
Size: 1357 bytes
Desc: not available
URL: <http://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/attachments/20240617/f3993d60/attachment.bin>


More information about the Dnsmasq-discuss mailing list