func_tests: disable FORTIFY_SOURCE for test_1_to_1_recvfrom

[kraj]

When built with glibc hardening (_FORTIFY_SOURCE), recvfrom() is wrapped by __recvfrom_chk(). The test_1_to_1_recvfrom test deliberately calls recvfrom() with an invalid buffer pointer ((char *)-1) to verify that EFAULT is returned.

On fortified builds, __recvfrom_chk() sees a buffer size of 0 and a non-zero length, treats this as a buffer overflow, and aborts with:

*** buffer overflow detected ***: terminated

This causes the test to fail with SIGABRT instead of exercising the kernel’s EFAULT path as intended.

Compile test_1_to_1_recvfrom without _FORTIFY_SOURCE so that the test can run to completion and correctly validate the EFAULT behavior, while keeping fortify enabled for the rest of code

[lxin]

@kraj,

I couldn't trigger it with:

# gcc --version
gcc (GCC) 15.2.1 20251022 (Red Hat 15.2.1-3)
# cd lksctp-tools
# ./bootstrap 
# CFLAGS="-O2 -D_FORTIFY_SOURCE=2" ./configure
# make

Can you show how the error '*** buffer overflow detected ***: terminated' was triggered on your env?

Thanks.

[kraj]

@kraj,

I couldn't trigger it with:

# gcc --version
gcc (GCC) 15.2.1 20251022 (Red Hat 15.2.1-3)
# cd lksctp-tools
# ./bootstrap 
# CFLAGS="-O2 -D_FORTIFY_SOURCE=2" ./configure
# make

Can you show how the error '*** buffer overflow detected ***: terminated' was triggered on your env?

Thanks.

I think you need glibc to be compiled with hardening options as well like what yocto does. Configure glibc build with --enable-fortify-source might give you a reproducer.