From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Metcalf Subject: [PATCH v8 06/14] task_isolation: provide strict mode configurable signal Date: Tue, 20 Oct 2015 16:36:04 -0400 Message-ID: <1445373372-6567-7-git-send-email-cmetcalf@ezchip.com> References: <1445373372-6567-1-git-send-email-cmetcalf@ezchip.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: In-Reply-To: <1445373372-6567-1-git-send-email-cmetcalf@ezchip.com> Sender: linux-kernel-owner@vger.kernel.org To: Gilad Ben Yossef , Steven Rostedt , Ingo Molnar , Peter Zijlstra , Andrew Morton , Rik van Riel , Tejun Heo , Frederic Weisbecker , Thomas Gleixner , "Paul E. McKenney" , Christoph Lameter , Viresh Kumar , Catalin Marinas , Will Deacon , Andy Lutomirski , linux-doc@vger.kernel.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Chris Metcalf List-Id: linux-api@vger.kernel.org Allow userspace to override the default SIGKILL delivered when a task_isolation process in STRICT mode does a syscall or otherwise synchronously enters the kernel. Signed-off-by: Chris Metcalf --- include/uapi/linux/prctl.h | 2 ++ kernel/isolation.c | 9 ++++++++- 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/include/uapi/linux/prctl.h b/include/uapi/linux/prctl.h index 2b8038b0d1e1..a5582ace987f 100644 --- a/include/uapi/linux/prctl.h +++ b/include/uapi/linux/prctl.h @@ -202,5 +202,7 @@ struct prctl_mm_map { #define PR_GET_TASK_ISOLATION 49 # define PR_TASK_ISOLATION_ENABLE (1 << 0) # define PR_TASK_ISOLATION_STRICT (1 << 1) +# define PR_TASK_ISOLATION_SET_SIG(sig) (((sig) & 0x7f) << 8) +# define PR_TASK_ISOLATION_GET_SIG(bits) (((bits) >> 8) & 0x7f) #endif /* _LINUX_PRCTL_H */ diff --git a/kernel/isolation.c b/kernel/isolation.c index 30db40098a35..0fa13b081bb4 100644 --- a/kernel/isolation.c +++ b/kernel/isolation.c @@ -84,8 +84,10 @@ void _task_isolation_enter(void) */ bool task_isolation_exception(const char *fmt, ...) { + siginfo_t info = {}; va_list args; char buf[100]; + int sig; /* RCU should have been enabled prior to this point. */ RCU_LOCKDEP_WARN(!rcu_is_watching(), "kernel entry without RCU"); @@ -97,7 +99,12 @@ bool task_isolation_exception(const char *fmt, ...) pr_warn("%s/%d: task_isolation strict mode violated by %s\n", current->comm, current->pid, buf); current->task_isolation_flags &= ~PR_TASK_ISOLATION_ENABLE; - send_sig(SIGKILL, current, 1); + + sig = PR_TASK_ISOLATION_GET_SIG(current->task_isolation_flags); + if (sig == 0) + sig = SIGKILL; + info.si_signo = sig; + send_sig_info(sig, &info, current); return true; } -- 2.1.2