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
We don't actually support core dumps, but some applications want to
get/set dumpability, which still has an effect in procfs.
Lack of support for set-uid binaries or fs creds simplifies things a
bit.
As-is, processes started via CreateProcess (i.e., init and sentryctl
exec) have normal dumpability. I'm a bit torn on whether sentryctl exec
tasks should be dumpable, but at least since they have no parent normal
UID/GID checks should protect them.
PiperOrigin-RevId: 251712714
Based on the guidelines at
https://opensource.google.com/docs/releasing/authors/.
1. $ rg -l "Google LLC" | xargs sed -i 's/Google LLC.*/The gVisor Authors./'
2. Manual fixup of "Google Inc" references.
3. Add AUTHORS file. Authors may request to be added to this file.
4. Point netstack AUTHORS to gVisor AUTHORS. Drop CONTRIBUTORS.
Fixes#209
PiperOrigin-RevId: 245823212
Change-Id: I64530b24ad021a7d683137459cafc510f5ee1de9
Added events for *ctl syscalls that may have multiple different commands.
For runsc, each syscall event is only logged once. For *ctl syscalls, use
the cmd as identifier, not only the syscall number.
PiperOrigin-RevId: 218015941
Change-Id: Ie3c19131ae36124861e9b492a7dbe1765d9e5e59
Jamie LiuandgVisor bot
William ChangandgVisor bot
Dean DengandgVisor bot
Michael PrattandShentubot
Fabricio VoznikaandShentubot
Ian GudgerandShentubot
Adin ScannellandShentubot
GooglerandAdin Scannell