From patchwork Tue Sep 24 06:44:20 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christian Brauner X-Patchwork-Id: 11157991 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 4FC1E14E5 for ; Tue, 24 Sep 2019 06:44:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 38111214AF for ; Tue, 24 Sep 2019 06:44:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2403946AbfIXGo3 (ORCPT ); Tue, 24 Sep 2019 02:44:29 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:37201 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2393206AbfIXGo2 (ORCPT ); Tue, 24 Sep 2019 02:44:28 -0400 Received: from [89.27.154.14] (helo=localhost.localdomain) by youngberry.canonical.com with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.86_2) (envelope-from ) id 1iCeYj-0000tF-CA; Tue, 24 Sep 2019 06:44:25 +0000 From: Christian Brauner To: christian.brauner@ubuntu.com Cc: keescook@chromium.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-parisc@vger.kernel.org, linux-s390@vger.kernel.org, linux-um@lists.infradead.org, luto@kernel.org, oleg@redhat.com, tglx@linutronix.de, wad@chromium.org, x86@kernel.org, Borislav Petkov Subject: [PATCH v1] seccomp: simplify secure_computing() Date: Tue, 24 Sep 2019 08:44:20 +0200 Message-Id: <20190924064420.6353-1-christian.brauner@ubuntu.com> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20190920131907.6886-1-christian.brauner@ubuntu.com> References: <20190920131907.6886-1-christian.brauner@ubuntu.com> MIME-Version: 1.0 Sender: linux-parisc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-parisc@vger.kernel.org Afaict, the struct seccomp_data argument to secure_computing() is unused by all current callers. So let's remove it. The argument was added in [1]. It was added because having the arch supply the syscall arguments used to be faster than having it done by secure_computing() (cf. Andy's comment in [2]). This is not true anymore though. /* References */ [1]: 2f275de5d1ed ("seccomp: Add a seccomp_data parameter secure_computing()") [2]: https://lore.kernel.org/r/CALCETrU_fs_At-hTpr231kpaAd0z7xJN4ku-DvzhRU6cvcJA_w@mail.gmail.com Signed-off-by: Christian Brauner Cc: Andy Lutomirski Cc: Thomas Gleixner Cc: Kees Cook Cc: Will Drewry Cc: Oleg Nesterov Cc: Borislav Petkov Cc: linux-arm-kernel@lists.infradead.org Cc: linux-parisc@vger.kernel.org Cc: linux-s390@vger.kernel.org Cc: linux-um@lists.infradead.org Cc: x86@kernel.org Acked-by: Borislav Petkov Acked-by: Andy Lutomirski --- /* v1 */ - Borislav Petkov : - provide context for the arg addition to secure_computing() in the commit message /* v0 */ Link: https://lore.kernel.org/r/20190920131907.6886-1-christian.brauner@ubuntu.com --- arch/arm/kernel/ptrace.c | 2 +- arch/arm64/kernel/ptrace.c | 2 +- arch/parisc/kernel/ptrace.c | 2 +- arch/s390/kernel/ptrace.c | 4 ++-- arch/um/kernel/skas/syscall.c | 2 +- arch/x86/entry/vsyscall/vsyscall_64.c | 2 +- include/linux/seccomp.h | 6 +++--- 7 files changed, 10 insertions(+), 10 deletions(-) diff --git a/arch/arm/kernel/ptrace.c b/arch/arm/kernel/ptrace.c index 324352787aea..b606cded90cd 100644 --- a/arch/arm/kernel/ptrace.c +++ b/arch/arm/kernel/ptrace.c @@ -923,7 +923,7 @@ asmlinkage int syscall_trace_enter(struct pt_regs *regs, int scno) /* Do seccomp after ptrace; syscall may have changed. */ #ifdef CONFIG_HAVE_ARCH_SECCOMP_FILTER - if (secure_computing(NULL) == -1) + if (secure_computing() == -1) return -1; #else /* XXX: remove this once OABI gets fixed */ diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index 3cf3b135027e..010a835302d3 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -1816,7 +1816,7 @@ int syscall_trace_enter(struct pt_regs *regs) } /* Do the secure computing after ptrace; failures should be fast. */ - if (secure_computing(NULL) == -1) + if (secure_computing() == -1) return -1; if (test_thread_flag(TIF_SYSCALL_TRACEPOINT)) diff --git a/arch/parisc/kernel/ptrace.c b/arch/parisc/kernel/ptrace.c index 9f6ff7bc06f9..f8c07dcbfb49 100644 --- a/arch/parisc/kernel/ptrace.c +++ b/arch/parisc/kernel/ptrace.c @@ -342,7 +342,7 @@ long do_syscall_trace_enter(struct pt_regs *regs) } /* Do the secure computing check after ptrace. */ - if (secure_computing(NULL) == -1) + if (secure_computing() == -1) return -1; #ifdef CONFIG_HAVE_SYSCALL_TRACEPOINTS diff --git a/arch/s390/kernel/ptrace.c b/arch/s390/kernel/ptrace.c index ad71132374f0..ed80bdfbf5fe 100644 --- a/arch/s390/kernel/ptrace.c +++ b/arch/s390/kernel/ptrace.c @@ -439,7 +439,7 @@ static int poke_user(struct task_struct *child, addr_t addr, addr_t data) long arch_ptrace(struct task_struct *child, long request, unsigned long addr, unsigned long data) { - ptrace_area parea; + ptrace_area parea; int copied, ret; switch (request) { @@ -856,7 +856,7 @@ asmlinkage long do_syscall_trace_enter(struct pt_regs *regs) } /* Do the secure computing check after ptrace. */ - if (secure_computing(NULL)) { + if (secure_computing()) { /* seccomp failures shouldn't expose any additional code. */ return -1; } diff --git a/arch/um/kernel/skas/syscall.c b/arch/um/kernel/skas/syscall.c index 44bb10785075..fc37259d5971 100644 --- a/arch/um/kernel/skas/syscall.c +++ b/arch/um/kernel/skas/syscall.c @@ -35,7 +35,7 @@ void handle_syscall(struct uml_pt_regs *r) goto out; /* Do the seccomp check after ptrace; failures should be fast. */ - if (secure_computing(NULL) == -1) + if (secure_computing() == -1) goto out; syscall = UPT_SYSCALL_NR(r); diff --git a/arch/x86/entry/vsyscall/vsyscall_64.c b/arch/x86/entry/vsyscall/vsyscall_64.c index e7c596dea947..b10cbf71a8cc 100644 --- a/arch/x86/entry/vsyscall/vsyscall_64.c +++ b/arch/x86/entry/vsyscall/vsyscall_64.c @@ -222,7 +222,7 @@ bool emulate_vsyscall(unsigned long error_code, */ regs->orig_ax = syscall_nr; regs->ax = -ENOSYS; - tmp = secure_computing(NULL); + tmp = secure_computing(); if ((!tmp && regs->orig_ax != syscall_nr) || regs->ip != address) { warn_bad_vsyscall(KERN_DEBUG, regs, "seccomp tried to change syscall nr or ip"); diff --git a/include/linux/seccomp.h b/include/linux/seccomp.h index 84868d37b35d..03583b6d1416 100644 --- a/include/linux/seccomp.h +++ b/include/linux/seccomp.h @@ -33,10 +33,10 @@ struct seccomp { #ifdef CONFIG_HAVE_ARCH_SECCOMP_FILTER extern int __secure_computing(const struct seccomp_data *sd); -static inline int secure_computing(const struct seccomp_data *sd) +static inline int secure_computing(void) { if (unlikely(test_thread_flag(TIF_SECCOMP))) - return __secure_computing(sd); + return __secure_computing(NULL); return 0; } #else @@ -59,7 +59,7 @@ struct seccomp { }; struct seccomp_filter { }; #ifdef CONFIG_HAVE_ARCH_SECCOMP_FILTER -static inline int secure_computing(struct seccomp_data *sd) { return 0; } +static inline int secure_computing(void) { return 0; } #else static inline void secure_computing_strict(int this_syscall) { return; } #endif