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e396a74222
Some distributions (such as Ubuntu) configure GCC so that
_FORTIFY_SOURCE is automatically enabled at -O1 or above. This results
in some fortified version of definitions of standard library functions
are included. While linker resolves the symbols, the fortified versions
might override the definitions in lib/string_override.c and reference to
those PLT entries in GLIBC. This is not a problem for the code in host,
but it is a disaster for the guest code. E.g., if build and run
x86/nested_emulation_test on Ubuntu 24.04 will encounter a L1 #PF due to
memset() reference to __memset_chk@plt.
The option -fno-builtin-memset is not helpful here, because those
fortified versions are not built-in but some definitions which are
included by header, they are for different intentions.
In order to eliminate the unpredictable behaviors may vary depending on
the linker and platform, add the "-U_FORTIFY_SOURCE" into CFLAGS to
prevent from introducing the fortified definitions.
Signed-off-by: Zhiquan Li <zhiquan_li@163.com>
Link: https://patch.msgid.link/20260122053551.548229-1-zhiquan_li@163.com
Fixes: 6b6f71484b ("KVM: selftests: Implement memcmp(), memcpy(), and memset() for guest use")
Cc: stable@vger.kernel.org
[sean: tag for stable]
Signed-off-by: Sean Christopherson <seanjc@google.com>