linux-kernel - [PATCH v3 0/4] arm64: kprobes: Fix some bugs in arm64 kprobes

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Thu, 25 Jul 2019 17:15:44 +0900
From:   Masami Hiramatsu <mhiramat@...nel.org>
To:     Catalin Marinas <catalin.marinas@....com>,
        Will Deacon <will.deacon@....com>
Cc:     mhiramat@...nel.org, linux-arm-kernel@...ts.infradead.org,
        linux-kernel@...r.kernel.org,
        Naresh Kamboju <naresh.kamboju@...aro.org>,
        Dan Rue <dan.rue@...aro.org>,
        Matt Hart <matthew.hart@...aro.org>,
        Anders Roxell <anders.roxell@...aro.org>,
        Daniel Diaz <daniel.diaz@...aro.org>
Subject: [PATCH v3 0/4] arm64: kprobes: Fix some bugs in arm64 kprobes 

Hi,

Here are the v3 patches which fixes kprobe bugs on arm64.
In this version I fixed some issues pointed by James and add Reviewed-by
and Acked-bys.

Background:
Naresh reported that recently ftracetest crashes kernel, and I found
there are 3 different bugs around the crash. In v1 thread, we found
one another bug of RCU and debug exception.

- Kprobes on arm64 doesn't recover pstate.D mask after single stepping.
  So after hitting kprobes, the debug flag status is changed.
- Some symbols which are called from blacklisted function, are not
  blacklisted.
- Debug exception is not visible to RCU, thus rcu_read_lock() cause
  a warning inside it.
- Debug exception handlers on arm64 is using rcu_read_lock(), but
  that is not needed because interrupts are disabled.

This series includes fixes for above bugs.

Thank you,

---

Masami Hiramatsu (4):
      arm64: kprobes: Recover pstate.D in single-step exception handler
      arm64: unwind: Prohibit probing on return_address()
      arm64: Make debug exception handlers visible from RCU
      arm64: Remove unneeded rcu_read_lock from debug handlers


 arch/arm64/include/asm/daifflags.h |    2 ++
 arch/arm64/kernel/debug-monitors.c |   14 +++++++------
 arch/arm64/kernel/probes/kprobes.c |   39 +++++------------------------------
 arch/arm64/kernel/return_address.c |    3 +++
 arch/arm64/kernel/stacktrace.c     |    3 +++
 arch/arm64/mm/fault.c              |   40 ++++++++++++++++++++++++++++++++++++
 6 files changed, 61 insertions(+), 40 deletions(-)

--
Masami Hiramatsu (Linaro) <mhiramat@...nel.org>