[PATCH v6 4/5] Capability: Complete PTRACE_MODE_SCHED
From: Casey Schaufler <hidden>
Date: 2018-11-05 19:06:03
Also in:
lkml
Subsystem:
capabilities, ptrace support, security subsystem, the rest · Maintainers:
Serge Hallyn, Oleg Nesterov, Paul Moore, James Morris, "Serge E. Hallyn", Linus Torvalds
From: Casey Schaufler <casey@schaufler-ca.com> Allow a complete ptrace access check with mode PTRACE_MODE_SCHED. Disable the inappropriate privilege check in the capability code that does incompatible locking. Signed-off-by: Casey Schaufler <redacted> --- kernel/ptrace.c | 2 -- security/commoncap.c | 3 ++- 2 files changed, 2 insertions(+), 3 deletions(-)
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 99cfddde6a55..0b6a9df51c3b 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c@@ -331,8 +331,6 @@ static int __ptrace_may_access(struct task_struct *task, unsigned int mode) !ptrace_has_cap(mm->user_ns, mode))) return -EPERM; - if (mode & PTRACE_MODE_SCHED) - return 0; return security_ptrace_access_check(task, mode); }
diff --git a/security/commoncap.c b/security/commoncap.c
index 2e489d6a3ac8..70a7e3d19c16 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c@@ -152,7 +152,8 @@ int cap_ptrace_access_check(struct task_struct *child, unsigned int mode) if (cred->user_ns == child_cred->user_ns && cap_issubset(child_cred->cap_permitted, *caller_caps)) goto out; - if (ns_capable(child_cred->user_ns, CAP_SYS_PTRACE)) + if (!(mode & PTRACE_MODE_SCHED) && + ns_capable(child_cred->user_ns, CAP_SYS_PTRACE)) goto out; ret = -EPERM; out:
--
2.17.1