diff options
| author | Dean Deng <deandeng@google.com> | 2021-02-24 02:01:38 -0800 |
|---|---|---|
| committer | gVisor bot <gvisor-bot@google.com> | 2021-02-24 02:03:16 -0800 |
| commit | acd516cfe2920006a5d2760c78bd2245d498023a (patch) | |
| tree | a60c57de55b821e6dd33bf2cfa37feb09903c2a2 /test/syscalls/linux/BUILD | |
| parent | 6e000d3424c0eed685483f54348c6b0a752a0435 (diff) | |
Add YAMA security module restrictions on ptrace(2).
Restrict ptrace(2) according to the default configurations of the YAMA security
module (mode 1), which is a common default among various Linux distributions.
The new access checks only permit the tracer to proceed if one of the following
conditions is met:
a) The tracer is already attached to the tracee.
b) The target is a descendant of the tracer.
c) The target has explicitly given permission to the tracer through the
PR_SET_PTRACER prctl.
d) The tracer has CAP_SYS_PTRACE.
See security/yama/yama_lsm.c for more details.
Note that these checks are added to CanTrace, which is checked for
PTRACE_ATTACH as well as some other operations, e.g., checking a process'
memory layout through /proc/[pid]/mem.
Since this patch adds restrictions to ptrace, it may break compatibility for
applications run by non-root users that, for instance, rely on being able to
trace processes that are not descended from the tracer (e.g., `gdb -p`). YAMA
restrictions can be turned off by setting /proc/sys/kernel/yama/ptrace_scope
to 0, or exceptions can be made on a per-process basis with the PR_SET_PTRACER
prctl.
Reported-by: syzbot+622822d8bca08c99e8c8@syzkaller.appspotmail.com
PiperOrigin-RevId: 359237723
Diffstat (limited to 'test/syscalls/linux/BUILD')
| -rw-r--r-- | test/syscalls/linux/BUILD | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/test/syscalls/linux/BUILD b/test/syscalls/linux/BUILD index 1a492bca3..f871426f0 100644 --- a/test/syscalls/linux/BUILD +++ b/test/syscalls/linux/BUILD @@ -1814,6 +1814,7 @@ cc_binary( "@com_google_absl//absl/flags:flag", "@com_google_absl//absl/time", gtest, + "//test/util:capability_util", "//test/util:file_descriptor", "//test/util:fs_util", "//test/util:logging", |