Check for memory leaks

[matttbe]

After the recent sync with Linus tree, our CI at MPTCP started to complain about memory leaks.

There is already one patch fixing that. I wanted to report this to you, thinking that it would affect debug builds running with KMemLeak, but it looks like leaks are not checked.

Would it be OK to look for that? By doing something like:

if [ ! -f "/sys/kernel/debug/kmemleak" ]; then
    return 0
fi

echo scan > /sys/kernel/debug/kmemleak
cat /sys/kernel/debug/kmemleak > "${KMEMLEAK}"
if [ -s "${KMEMLEAK}" ]; then
    ./scripts/decode_stacktrace.sh (...) < "${KMEMLEAK}"
    <mark as fail>
    return 1
fi

[kuba-moo]

More than OK, it'd be great to add!
We just need to make sure to run the stack traces thru something like crash_finger_print() and filter out known ones that come from the Big Penguin's tree.

[matttbe]

KMemLeak support has been added by @kuba-moo (thanks!) in be5f03c. We can then close this discussion.