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#!/bin/bash
# SPDX-License-Identifier: GPL-2.0
#
# Under kCFI an indirect call checks a type hash before jumping, and traps on a
# mismatch. Two things belong to the calling function and must come with it
# into a patch:
#
# - the __cfi_<func> prefix symbol holding the hash. Lose it and the patched
# function has no type identity, so indirect calls to it trap.
# - its .kcfi_traps entry. Lose that and the trap is not recognised as a
# CFI failure, so what should be a clean report becomes an oops.
#
# Neither shows up at build time.
. "$(dirname "$0")/../lib.sh"
clang_only "kCFI is a Clang feature"
setup
# Declared above that this is Clang's; a given Clang may still be too old.
cc_supports -fsanitize=kcfi ||
probe_skip "this clang does not support -fsanitize=kcfi"
build_pair kcfi.c -fsanitize=kcfi
assert_input_section .kcfi_traps
assert_input_symbol __cfi_target
run_diff
assert_patched target
# The prefix symbol comes with its function ...
assert_symbol __cfi_target
# ... and so does the trap entry.
assert_section .kcfi_traps
pass "kCFI prefix symbol and trap entry carried with the patched function"
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