Hi,
This is a series of patches to fix kprobes issues on the
kernel with CONFIG_RETPOLINE=y.
- [1/3]: This introduces __x86_indirect_thunk_* boundary
symbols so that kprobes easily identify those functions.
- [2/3]: Mark __x86_indirect_thunk_* as blacklisted function
for kprobes, since it can be called from other
blacklisted functions.
- [3/3]: Check jmp instructions in the probe target function
whether it jumps into the __x86_indirect_thunk_*,
because it is equal to an indirect jump instruction.
Side effect: [1/3] will move __x86_indirect_thunk_* functions
in kernel text area. Of course those functions were in the
.text area, but placed in right after _etext. This just moves
it right before the _etext.
Thank you,
---
Masami Hiramatsu (3):
retpoline: Introduce start/end markers of indirect thunk
kprobes/x86: Blacklist indirect thunk functions for kprobes
kprobes/x86: Disable optimizing on the function jumps to indirect thunk
arch/x86/include/asm/nospec-branch.h | 3 +++
arch/x86/kernel/kprobes/opt.c | 23 +++++++++++++++++++++-
arch/x86/kernel/vmlinux.lds.S | 35 ++++++++++++++++++++++++++++++++++
arch/x86/lib/retpoline.S | 3 ++-
4 files changed, 62 insertions(+), 2 deletions(-)
--
Masami Hiramatsu (Linaro) <[email protected]>
