The declaration of struct shfl_string used trailing fake flexible arrays for the string member. This was tripping FORTIFY_SOURCE since commit df8fc4e934c1 ("kbuild: Enable -fstrict-flex-arrays=3"). Replace the utf8 and utf16 members with actual flexible arrays, drop the unused ucs2 member, and retriain a 2 byte padding to keep the structure size the same. Reported-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx> Closes: https://lore.kernel.org/lkml/ab3a70e9-60ed-0f13-e3d4-8866eaccc8c1@xxxxxxxxxxxx/ Tested-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> --- fs/vboxsf/shfl_hostintf.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/vboxsf/shfl_hostintf.h b/fs/vboxsf/shfl_hostintf.h index aca829062c12..069a019c9247 100644 --- a/fs/vboxsf/shfl_hostintf.h +++ b/fs/vboxsf/shfl_hostintf.h @@ -68,9 +68,9 @@ struct shfl_string { /** UTF-8 or UTF-16 string. Nul terminated. */ union { - u8 utf8[2]; - u16 utf16[1]; - u16 ucs2[1]; /* misnomer, use utf16. */ + u8 legacy_padding[2]; + DECLARE_FLEX_ARRAY(u8, utf8); + DECLARE_FLEX_ARRAY(u16, utf16); } string; }; VMMDEV_ASSERT_SIZE(shfl_string, 6); -- 2.34.1