From patchwork Fri Apr 29 21:48:28 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Eric W. Biederman" X-Patchwork-Id: 568508 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 43D70C433EF for ; Fri, 29 Apr 2022 22:07:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349989AbiD2WKn (ORCPT ); Fri, 29 Apr 2022 18:10:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46300 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234141AbiD2WKn (ORCPT ); Fri, 29 Apr 2022 18:10:43 -0400 X-Greylist: delayed 1164 seconds by postgrey-1.37 at lindbergh.monkeyblade.net; Fri, 29 Apr 2022 15:07:23 PDT Received: from out02.mta.xmission.com (out02.mta.xmission.com [166.70.13.232]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E9668DBD36; Fri, 29 Apr 2022 15:07:22 -0700 (PDT) Received: from in02.mta.xmission.com ([166.70.13.52]:54628) by out02.mta.xmission.com with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1nkYU4-00AIHv-5u; Fri, 29 Apr 2022 15:49:04 -0600 Received: from ip68-227-174-4.om.om.cox.net ([68.227.174.4]:36464 helo=localhost.localdomain) by in02.mta.xmission.com with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1nkYU1-007RIp-SJ; Fri, 29 Apr 2022 15:49:03 -0600 From: "Eric W. Biederman" To: linux-kernel@vger.kernel.org Cc: rjw@rjwysocki.net, Oleg Nesterov , mingo@kernel.org, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, mgorman@suse.de, bigeasy@linutronix.de, Will Deacon , tj@kernel.org, linux-pm@vger.kernel.org, Peter Zijlstra , Richard Weinberger , Anton Ivanov , Johannes Berg , linux-um@lists.infradead.org, Chris Zankel , Max Filippov , linux-xtensa@linux-xtensa.org, Kees Cook , Jann Horn , linux-ia64@vger.kernel.org, "Eric W. Biederman" , stable@vger.kernel.org Date: Fri, 29 Apr 2022 16:48:28 -0500 Message-Id: <20220429214837.386518-3-ebiederm@xmission.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <87k0b7v9yk.fsf_-_@email.froward.int.ebiederm.org> References: <87k0b7v9yk.fsf_-_@email.froward.int.ebiederm.org> MIME-Version: 1.0 X-XM-SPF: eid=1nkYU1-007RIp-SJ; ; ; mid=<20220429214837.386518-3-ebiederm@xmission.com>; ; ; hst=in02.mta.xmission.com; ; ; ip=68.227.174.4; ; ; frm=ebiederm@xmission.com; ; ; spf=softfail X-XM-AID: U2FsdGVkX180O+oNrK8kueX5JDUgMLmEvvwqhHxDh38= X-SA-Exim-Connect-IP: 68.227.174.4 X-SA-Exim-Mail-From: ebiederm@xmission.com Subject: [PATCH v2 03/12] ptrace/um: Replace PT_DTRACE with TIF_SINGLESTEP X-SA-Exim-Version: 4.2.1 (built Sat, 08 Feb 2020 21:53:50 +0000) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org User mode linux is the last user of the PT_DTRACE flag. Using the flag to indicate single stepping is a little confusing and worse changing tsk->ptrace without locking could potentionally cause problems. So use a thread info flag with a better name instead of flag in tsk->ptrace. Remove the definition PT_DTRACE as uml is the last user. Cc: stable@vger.kernel.org Acked-by: Johannes Berg Signed-off-by: "Eric W. Biederman" --- arch/um/include/asm/thread_info.h | 2 ++ arch/um/kernel/exec.c | 2 +- arch/um/kernel/process.c | 2 +- arch/um/kernel/ptrace.c | 8 ++++---- arch/um/kernel/signal.c | 4 ++-- include/linux/ptrace.h | 1 - 6 files changed, 10 insertions(+), 9 deletions(-) diff --git a/arch/um/include/asm/thread_info.h b/arch/um/include/asm/thread_info.h index 1395cbd7e340..c7b4b49826a2 100644 --- a/arch/um/include/asm/thread_info.h +++ b/arch/um/include/asm/thread_info.h @@ -60,6 +60,7 @@ static inline struct thread_info *current_thread_info(void) #define TIF_RESTORE_SIGMASK 7 #define TIF_NOTIFY_RESUME 8 #define TIF_SECCOMP 9 /* secure computing */ +#define TIF_SINGLESTEP 10 /* single stepping userspace */ #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) @@ -68,5 +69,6 @@ static inline struct thread_info *current_thread_info(void) #define _TIF_MEMDIE (1 << TIF_MEMDIE) #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) #define _TIF_SECCOMP (1 << TIF_SECCOMP) +#define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP) #endif diff --git a/arch/um/kernel/exec.c b/arch/um/kernel/exec.c index c85e40c72779..58938d75871a 100644 --- a/arch/um/kernel/exec.c +++ b/arch/um/kernel/exec.c @@ -43,7 +43,7 @@ void start_thread(struct pt_regs *regs, unsigned long eip, unsigned long esp) { PT_REGS_IP(regs) = eip; PT_REGS_SP(regs) = esp; - current->ptrace &= ~PT_DTRACE; + clear_thread_flag(TIF_SINGLESTEP); #ifdef SUBARCH_EXECVE1 SUBARCH_EXECVE1(regs->regs); #endif diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c index 80504680be08..88c5c7844281 100644 --- a/arch/um/kernel/process.c +++ b/arch/um/kernel/process.c @@ -335,7 +335,7 @@ int singlestepping(void * t) { struct task_struct *task = t ? t : current; - if (!(task->ptrace & PT_DTRACE)) + if (!test_thread_flag(TIF_SINGLESTEP)) return 0; if (task->thread.singlestep_syscall) diff --git a/arch/um/kernel/ptrace.c b/arch/um/kernel/ptrace.c index bfaf6ab1ac03..5154b27de580 100644 --- a/arch/um/kernel/ptrace.c +++ b/arch/um/kernel/ptrace.c @@ -11,7 +11,7 @@ void user_enable_single_step(struct task_struct *child) { - child->ptrace |= PT_DTRACE; + set_tsk_thread_flag(child, TIF_SINGLESTEP); child->thread.singlestep_syscall = 0; #ifdef SUBARCH_SET_SINGLESTEPPING @@ -21,7 +21,7 @@ void user_enable_single_step(struct task_struct *child) void user_disable_single_step(struct task_struct *child) { - child->ptrace &= ~PT_DTRACE; + clear_tsk_thread_flag(child, TIF_SINGLESTEP); child->thread.singlestep_syscall = 0; #ifdef SUBARCH_SET_SINGLESTEPPING @@ -120,7 +120,7 @@ static void send_sigtrap(struct uml_pt_regs *regs, int error_code) } /* - * XXX Check PT_DTRACE vs TIF_SINGLESTEP for singlestepping check and + * XXX Check TIF_SINGLESTEP for singlestepping check and * PT_PTRACED vs TIF_SYSCALL_TRACE for syscall tracing check */ int syscall_trace_enter(struct pt_regs *regs) @@ -144,7 +144,7 @@ void syscall_trace_leave(struct pt_regs *regs) audit_syscall_exit(regs); /* Fake a debug trap */ - if (ptraced & PT_DTRACE) + if (test_thread_flag(TIF_SINGLESTEP)) send_sigtrap(®s->regs, 0); if (!test_thread_flag(TIF_SYSCALL_TRACE)) diff --git a/arch/um/kernel/signal.c b/arch/um/kernel/signal.c index 88cd9b5c1b74..ae4658f576ab 100644 --- a/arch/um/kernel/signal.c +++ b/arch/um/kernel/signal.c @@ -53,7 +53,7 @@ static void handle_signal(struct ksignal *ksig, struct pt_regs *regs) unsigned long sp; int err; - if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED)) + if (test_thread_flag(TIF_SINGLESTEP) && (current->ptrace & PT_PTRACED)) singlestep = 1; /* Did we come from a system call? */ @@ -128,7 +128,7 @@ void do_signal(struct pt_regs *regs) * on the host. The tracing thread will check this flag and * PTRACE_SYSCALL if necessary. */ - if (current->ptrace & PT_DTRACE) + if (test_thread_flag(TIF_SINGLESTEP)) current->thread.singlestep_syscall = is_syscall(PT_REGS_IP(¤t->thread.regs)); diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h index 15b3d176b6b4..4c06f9f8ef3f 100644 --- a/include/linux/ptrace.h +++ b/include/linux/ptrace.h @@ -30,7 +30,6 @@ extern int ptrace_access_vm(struct task_struct *tsk, unsigned long addr, #define PT_SEIZED 0x00010000 /* SEIZE used, enable new behavior */ #define PT_PTRACED 0x00000001 -#define PT_DTRACE 0x00000002 /* delayed trace (used on m68k, i386) */ #define PT_OPT_FLAG_SHIFT 3 /* PT_TRACE_* event enable flags */ From patchwork Fri Apr 29 21:48:29 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Eric W. Biederman" X-Patchwork-Id: 568509 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 786D8C433EF for ; Fri, 29 Apr 2022 21:49:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239514AbiD2Vw2 (ORCPT ); Fri, 29 Apr 2022 17:52:28 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47468 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239499AbiD2Vw1 (ORCPT ); Fri, 29 Apr 2022 17:52:27 -0400 Received: from out01.mta.xmission.com (out01.mta.xmission.com [166.70.13.231]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8878DDB494; Fri, 29 Apr 2022 14:49:08 -0700 (PDT) Received: from in02.mta.xmission.com ([166.70.13.52]:49802) by out01.mta.xmission.com with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1nkYU7-007OC4-8V; Fri, 29 Apr 2022 15:49:07 -0600 Received: from ip68-227-174-4.om.om.cox.net ([68.227.174.4]:36464 helo=localhost.localdomain) by in02.mta.xmission.com with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1nkYU6-007RIp-6O; Fri, 29 Apr 2022 15:49:06 -0600 From: "Eric W. Biederman" To: linux-kernel@vger.kernel.org Cc: rjw@rjwysocki.net, Oleg Nesterov , mingo@kernel.org, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, mgorman@suse.de, bigeasy@linutronix.de, Will Deacon , tj@kernel.org, linux-pm@vger.kernel.org, Peter Zijlstra , Richard Weinberger , Anton Ivanov , Johannes Berg , linux-um@lists.infradead.org, Chris Zankel , Max Filippov , linux-xtensa@linux-xtensa.org, Kees Cook , Jann Horn , linux-ia64@vger.kernel.org, "Eric W. Biederman" , stable@vger.kernel.org Date: Fri, 29 Apr 2022 16:48:29 -0500 Message-Id: <20220429214837.386518-4-ebiederm@xmission.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <87k0b7v9yk.fsf_-_@email.froward.int.ebiederm.org> References: <87k0b7v9yk.fsf_-_@email.froward.int.ebiederm.org> MIME-Version: 1.0 X-XM-SPF: eid=1nkYU6-007RIp-6O; ; ; mid=<20220429214837.386518-4-ebiederm@xmission.com>; ; ; hst=in02.mta.xmission.com; ; ; ip=68.227.174.4; ; ; frm=ebiederm@xmission.com; ; ; spf=softfail X-XM-AID: U2FsdGVkX1+l1YL71w1w1BKCUUmYDmX3zFUC3cyNA9I= X-SA-Exim-Connect-IP: 68.227.174.4 X-SA-Exim-Mail-From: ebiederm@xmission.com Subject: [PATCH v2 04/12] ptrace/xtensa: Replace PT_SINGLESTEP with TIF_SINGLESTEP X-SA-Exim-Version: 4.2.1 (built Sat, 08 Feb 2020 21:53:50 +0000) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org xtensa is the last user of the PT_SINGLESTEP flag. Changing tsk->ptrace in user_enable_single_step and user_disable_single_step without locking could potentiallly cause problems. So use a thread info flag instead of a flag in tsk->ptrace. Use TIF_SINGLESTEP that xtensa already had defined but unused. Remove the definitions of PT_SINGLESTEP and PT_BLOCKSTEP as they have no more users. Cc: stable@vger.kernel.org Acked-by: Max Filippov Signed-off-by: "Eric W. Biederman" --- arch/xtensa/kernel/ptrace.c | 4 ++-- arch/xtensa/kernel/signal.c | 4 ++-- include/linux/ptrace.h | 6 ------ 3 files changed, 4 insertions(+), 10 deletions(-) diff --git a/arch/xtensa/kernel/ptrace.c b/arch/xtensa/kernel/ptrace.c index 323c678a691f..b952e67cc0cc 100644 --- a/arch/xtensa/kernel/ptrace.c +++ b/arch/xtensa/kernel/ptrace.c @@ -225,12 +225,12 @@ const struct user_regset_view *task_user_regset_view(struct task_struct *task) void user_enable_single_step(struct task_struct *child) { - child->ptrace |= PT_SINGLESTEP; + set_tsk_thread_flag(child, TIF_SINGLESTEP); } void user_disable_single_step(struct task_struct *child) { - child->ptrace &= ~PT_SINGLESTEP; + clear_tsk_thread_flag(child, TIF_SINGLESTEP); } /* diff --git a/arch/xtensa/kernel/signal.c b/arch/xtensa/kernel/signal.c index 6f68649e86ba..ac50ec46c8f1 100644 --- a/arch/xtensa/kernel/signal.c +++ b/arch/xtensa/kernel/signal.c @@ -473,7 +473,7 @@ static void do_signal(struct pt_regs *regs) /* Set up the stack frame */ ret = setup_frame(&ksig, sigmask_to_save(), regs); signal_setup_done(ret, &ksig, 0); - if (current->ptrace & PT_SINGLESTEP) + if (test_thread_flag(TIF_SINGLESTEP)) task_pt_regs(current)->icountlevel = 1; return; @@ -499,7 +499,7 @@ static void do_signal(struct pt_regs *regs) /* If there's no signal to deliver, we just restore the saved mask. */ restore_saved_sigmask(); - if (current->ptrace & PT_SINGLESTEP) + if (test_thread_flag(TIF_SINGLESTEP)) task_pt_regs(current)->icountlevel = 1; return; } diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h index 4c06f9f8ef3f..c952c5ba8fab 100644 --- a/include/linux/ptrace.h +++ b/include/linux/ptrace.h @@ -46,12 +46,6 @@ extern int ptrace_access_vm(struct task_struct *tsk, unsigned long addr, #define PT_EXITKILL (PTRACE_O_EXITKILL << PT_OPT_FLAG_SHIFT) #define PT_SUSPEND_SECCOMP (PTRACE_O_SUSPEND_SECCOMP << PT_OPT_FLAG_SHIFT) -/* single stepping state bits (used on ARM and PA-RISC) */ -#define PT_SINGLESTEP_BIT 31 -#define PT_SINGLESTEP (1< X-Patchwork-Id: 567717 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5F882C433FE for ; Fri, 29 Apr 2022 21:49:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239618AbiD2Vwl (ORCPT ); Fri, 29 Apr 2022 17:52:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47550 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239590AbiD2Vwd (ORCPT ); Fri, 29 Apr 2022 17:52:33 -0400 Received: from out01.mta.xmission.com (out01.mta.xmission.com [166.70.13.231]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8C817DB4B6; Fri, 29 Apr 2022 14:49:14 -0700 (PDT) Received: from in02.mta.xmission.com ([166.70.13.52]:49872) by out01.mta.xmission.com with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1nkYUD-007OE5-Gn; Fri, 29 Apr 2022 15:49:13 -0600 Received: from ip68-227-174-4.om.om.cox.net ([68.227.174.4]:36464 helo=localhost.localdomain) by in02.mta.xmission.com with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1nkYUC-007RIp-Gl; Fri, 29 Apr 2022 15:49:13 -0600 From: "Eric W. Biederman" To: linux-kernel@vger.kernel.org Cc: rjw@rjwysocki.net, Oleg Nesterov , mingo@kernel.org, vincent.guittot@linaro.org, dietmar.eggemann@arm.com, rostedt@goodmis.org, mgorman@suse.de, bigeasy@linutronix.de, Will Deacon , tj@kernel.org, linux-pm@vger.kernel.org, Peter Zijlstra , Richard Weinberger , Anton Ivanov , Johannes Berg , linux-um@lists.infradead.org, Chris Zankel , Max Filippov , linux-xtensa@linux-xtensa.org, Kees Cook , Jann Horn , linux-ia64@vger.kernel.org, "Eric W. Biederman" , stable@vger.kernel.org, Al Viro Date: Fri, 29 Apr 2022 16:48:31 -0500 Message-Id: <20220429214837.386518-6-ebiederm@xmission.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <87k0b7v9yk.fsf_-_@email.froward.int.ebiederm.org> References: <87k0b7v9yk.fsf_-_@email.froward.int.ebiederm.org> MIME-Version: 1.0 X-XM-SPF: eid=1nkYUC-007RIp-Gl; ; ; mid=<20220429214837.386518-6-ebiederm@xmission.com>; ; ; hst=in02.mta.xmission.com; ; ; ip=68.227.174.4; ; ; frm=ebiederm@xmission.com; ; ; spf=softfail X-XM-AID: U2FsdGVkX1+vbrOvInw4J3zemlYv0MOslvPzk7U8i+A= X-SA-Exim-Connect-IP: 68.227.174.4 X-SA-Exim-Mail-From: ebiederm@xmission.com Subject: [PATCH v2 06/12] ptrace: Reimplement PTRACE_KILL by always sending SIGKILL X-SA-Exim-Version: 4.2.1 (built Sat, 08 Feb 2020 21:53:50 +0000) X-SA-Exim-Scanned: Yes (on in02.mta.xmission.com) Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org Call send_sig_info in PTRACE_KILL instead of ptrace_resume. Calling ptrace_resume is not safe to call if the task has not been stopped with ptrace_freeze_traced. Cc: stable@vger.kernel.org Reported-by: Al Viro Suggested-by: Al Viro Signed-off-by: "Eric W. Biederman" --- kernel/ptrace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/ptrace.c b/kernel/ptrace.c index ccc4b465775b..43da5764b6f3 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -1238,7 +1238,7 @@ int ptrace_request(struct task_struct *child, long request, case PTRACE_KILL: if (child->exit_state) /* already dead */ return 0; - return ptrace_resume(child, request, SIGKILL); + return send_sig_info(SIGKILL, SEND_SIG_NOINFO, child); #ifdef CONFIG_HAVE_ARCH_TRACEHOOK case PTRACE_GETREGSET: