* [PATCH bpf v2 0/4] Fix 32-bit arch and compat support for the kprobe_multi attach type
@ 2022-05-16 23:04 Eugene Syromiatnikov
0 siblings, 0 replies; only message in thread
From: Eugene Syromiatnikov @ 2022-05-16 23:04 UTC (permalink / raw)
To: Jiri Olsa, Masami Hiramatsu, Steven Rostedt, Ingo Molnar,
Alexei Starovoitov, Daniel Borkmann
Cc: Andrii Nakryiko, Martin KaFai Lau, Song Liu, Yonghong Song,
John Fastabend, KP Singh, netdev, bpf, linux-kernel, Shuah Khan,
linux-kselftest
As suggested in [1], the kprobe_multi interface is to be fixed for 32-bit
architectures and compat, rather then disabled. As it turned out,
there are a couple of additional problems that are to be addressed:
- the absence of size overflow checks, leading to possible
out-of-bounds writes (addressed by the first patch);
- the assumption that long has the same size as u64, which would make
cookies arrays size calculation incorrect on 32-bit architectures
(addressed by the second patch);
- the addrs array passing API, that is incompatible with compat and has
to be changed (addressed in the fourth patch): those are kernel
addresses and not user ones (as was incorrectly stated in [2]);
this change is only semantical for 64-bit user/kernelspace,
so it shouldn't impact ABI there, at least.
[1] https://lore.kernel.org/lkml/CAADnVQ+2gwhcMht4PuDnDOFKY68Wsq8QFz4Y69NBX_TLaSexQQ@mail.gmail.com/
[2] https://lore.kernel.org/lkml/20220510184155.GA8295@asgard.redhat.com/
v2:
- Fixed the isses reported by CI
v1: https://lore.kernel.org/lkml/20220516182657.GA28596@asgard.redhat.com/
Eugene Syromiatnikov (4):
bpf_trace: check size for overflow in bpf_kprobe_multi_link_attach
bpf_trace: support 32-bit kernels in bpf_kprobe_multi_link_attach
bpf_trace: handle compat in kprobe_multi_resolve_syms
bpf_trace: pass array of u64 values in kprobe_multi.addrs
kernel/trace/bpf_trace.c | 62 ++++++++++++++++------
tools/lib/bpf/bpf.h | 2 +-
tools/lib/bpf/libbpf.c | 8 +--
tools/lib/bpf/libbpf.h | 2 +-
.../testing/selftests/bpf/prog_tests/bpf_cookie.c | 2 +-
.../selftests/bpf/prog_tests/kprobe_multi_test.c | 8 +--
6 files changed, 56 insertions(+), 28 deletions(-)
--
2.1.4
^ permalink raw reply [flat|nested] only message in thread
only message in thread, other threads:[~2022-05-16 23:05 UTC | newest]
Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2022-05-16 23:04 [PATCH bpf v2 0/4] Fix 32-bit arch and compat support for the kprobe_multi attach type Eugene Syromiatnikov
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).