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Bugs found with Address Sanitizer in syslog-ng, monit, cmake

Lately a couple of updates have fixed issues that I discovered while testing software with Address Sanitizer (ASAN). I'll publish these combined. Once again these show that a lot of software hasn't been tested with ASAN and what kind of bugs it can uncover.

In syslog-ng a function returns an error -1 that gets stored in an unsigned variable. This cannot be stored and a subsequent check for the error value fails, this later leads to a heap out of bounds memory read. This was fixed in syslog-ng 3.7.3.
Upstream bug report
Pull request / patch
syslog-ng 3.7.3 release notes

In the monit system monitoring tool a heap overflow was discovered. A call to sscanf would write a string of length 256 into a 256 byte long buffer. However this fails to consider the trailing zero byte of that string, therefore causing a one byte heap overflow. This was fixed in monit 5.16.
Commit / fix

In the compilation tool cmake a use after free error was found. This happened becaused a variable was used in a comparison and was free'd during that comparison operation. This was fixed in cmake 3.5.0.
Upstream bug report
Commit / fix