The abuild-tar binary can read past the end of an invalid tar header if
the contained link name does not end with a terminating NUL character.
In this case it reads past the end of hdr.linkname and maybe even past
the end of the header if no further NUL bytes are contained.
The strnlen function is used in apk-tools for such cases as well, so I
recommend to use it here too.
How to reproduce (compile abuild-tar with -fsanitize=address):
cat > poc.tar.b64 << EOF
b3dvAAAAAAAAAAADAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAADAwMDAwMDAAMDAwMDAw
MAAwMDAwMDAwADAwMDAwMDAwMDAwADAwMDAwMDAwMDAwADAwMDAwMAAAMm93b29vb29vb29vb29v
b29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29v
b29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29v
b29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29v
b29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29v
b29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29v
b29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb29vb28=
EOF
base64 -d < poc.tar.b64 | abuild-tar --hash
use a fake openssl for abuild-keykey and pre-generate the abuild keys.
This makes tests run significantly faster as we dont need to generate
new keys for each abuild-keygen test.
-v outputs everything from the tests, which has a lot of very
uninteresting and spammy data. all we really care about is failures, so
print only the errorlogs on failure by default. this is analogous to the
cmake output on failure
As demonstrated in b7813c3 (abump: demonstrate abump environment
polution, 2022-10-15), sourcing APKBUILDs in abump polutes it's
environment.
Address that by sourcing the APKBUILD in a subshell as well as some of
the checks following it that need the information from the APKBUILD.
That information is not used any later, it's not an issue that it's
discarded outside of the subshell.
abump sources the APKBUILD to be able to check some variables. When the
APKBUILD exports variables in the global scope, that affects the abump
environment as well.
When abump then executes abuild, it will inherrit the environment from
abump. This is an issue under the following circumstances:
* The APKBUILD only updates the value of an exported variable if it's
not set
* The default value includes a variable set by abuild, like `$srcdir`.
Because the variable is set by abuild, but not abump, the resulting
exported variable is different. Because it's then set incorrectly in the
abump environment, it's no longer updated with the correct variable when
abuild is invoked.
Some languages (such as Hare) do not support position-independent
executables. Such cases require extra care and scrutiny, but should not
be entirely disallowed.
Natanael Copa
Samanta Navarro
psykose
Kevin Daudt
Noel Kuntze
ptrcnull
Drew DeVault
xdavidwu
Jakub Panek