hi,
we recently had several requests for tetragon to be able to change
user application function return value or divert its execution through
instruction pointer change.
This patchset adds support for uprobe program to change app's registers
including instruction pointer.
v3 changes:
- deny attach of kprobe,multi with kprobe_write_ctx set [Alexei]
- added more tests for denied kprobe attachment
thanks,
jirka
---
Jiri Olsa (6):
bpf: Allow uprobe program to change context registers
uprobe: Do not emulate/sstep original instruction when ip is changed
selftests/bpf: Add uprobe context registers changes test
selftests/bpf: Add uprobe context ip register change test
selftests/bpf: Add kprobe write ctx attach test
selftests/bpf: Add kprobe multi write ctx attach test
include/linux/bpf.h | 1 +
kernel/events/core.c | 4 +++
kernel/events/uprobes.c | 7 +++++
kernel/trace/bpf_trace.c | 7 +++--
tools/testing/selftests/bpf/prog_tests/attach_probe.c | 28
+++++++++++++++++
tools/testing/selftests/bpf/prog_tests/kprobe_multi_test.c | 27
++++++++++++++++
tools/testing/selftests/bpf/prog_tests/uprobe.c | 156
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
tools/testing/selftests/bpf/progs/kprobe_write_ctx.c | 22 +++++++++++++
tools/testing/selftests/bpf/progs/test_uprobe.c | 38
+++++++++++++++++++++++
9 files changed, 287 insertions(+), 3 deletions(-)
create mode 100644 tools/testing/selftests/bpf/progs/kprobe_write_ctx.c
