Attaching fexit probes to functions marked with __noreturn may lead to
unpredictable behavior. To avoid this, we will reject attaching probes to
such functions. Currently, there is no ideal solution, so we will hardcode
a check for all __noreturn functions. Since objtool already handles
this, we will leverage its implementation.
Once a more robust solution is found, this workaround can be removed.
Yafang Shao (3):
objtool: Move noreturns.h to a common location
bpf: Reject attaching fexit to functions annotated with __noreturn
selftests/bpf: Add selftest for attaching fexit to __noreturn
functions
{tools/objtool => include/linux}/noreturns.h | 0
kernel/bpf/verifier.c | 10 ++++
tools/include/linux/noreturns.h | 52 +++++++++++++++++++
tools/objtool/Documentation/objtool.txt | 3 +-
tools/objtool/check.c | 2 +-
.../bpf/prog_tests/fexit_noreturns.c | 13 +++++
.../selftests/bpf/progs/fexit_noreturns.c | 13 +++++
7 files changed, 91 insertions(+), 2 deletions(-)
rename {tools/objtool => include/linux}/noreturns.h (100%)
create mode 100644 tools/include/linux/noreturns.h
create mode 100644 tools/testing/selftests/bpf/prog_tests/fexit_noreturns.c
create mode 100644 tools/testing/selftests/bpf/progs/fexit_noreturns.c
--
2.43.5
