From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from na01-bl2-obe.outbound.protection.outlook.com (mail-bl2on0107.outbound.protection.outlook.com [65.55.169.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id E83211A086D for ; Wed, 11 Feb 2015 19:36:34 +1100 (AEDT) From: Bogdan Purcareata To: , , Subject: [PATCH v2 1/3] powerpc: Don't force ENOSYS as error on syscall fail Date: Wed, 11 Feb 2015 08:36:16 +0000 Message-ID: <1423643778-32525-2-git-send-email-bogdan.purcareata@freescale.com> In-Reply-To: <1423643778-32525-1-git-send-email-bogdan.purcareata@freescale.com> References: <1423643778-32525-1-git-send-email-bogdan.purcareata@freescale.com> MIME-Version: 1.0 Content-Type: text/plain Cc: pmoore@redhat.com, linux-kernel@vger.kernel.org, Bogdan Purcareata , strosake@linux.vnet.ibm.com List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , In certain scenarios - e.g. seccomp filtering with ERRNO as default action - the system call fails for other reasons than the syscall not being available. The seccomp filter can be configured to store a user-defined error code on return from a blacklisted syscall. Don't always set ENOSYS on do_syscall_trace_enter failure. v2: - move setting ENOSYS as errno from the syscall entry assembly to do_syscall_trace_enter, only in the specific case Signed-off-by: Bogdan Purcareata --- arch/powerpc/kernel/entry_32.S | 2 +- arch/powerpc/kernel/entry_64.S | 1 - arch/powerpc/kernel/ptrace.c | 4 +++- 3 files changed, 4 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S index 10a0935..d2c58a3 100644 --- a/arch/powerpc/kernel/entry_32.S +++ b/arch/powerpc/kernel/entry_32.S @@ -425,7 +425,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_NEED_PAIRED_STWCX) b 1b #endif /* CONFIG_44x */ -66: li r3,-ENOSYS +66: b ret_from_syscall .globl ret_from_fork diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index 194e46d..0111e04 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -269,7 +269,6 @@ syscall_dotrace: b .Lsyscall_dotrace_cont syscall_enosys: - li r3,-ENOSYS b syscall_exit syscall_exit_work: diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c index f21897b..d82fd0b 100644 --- a/arch/powerpc/kernel/ptrace.c +++ b/arch/powerpc/kernel/ptrace.c @@ -1775,13 +1775,15 @@ long do_syscall_trace_enter(struct pt_regs *regs) secure_computing_strict(regs->gpr[0]); if (test_thread_flag(TIF_SYSCALL_TRACE) && - tracehook_report_syscall_entry(regs)) + tracehook_report_syscall_entry(regs)) { /* * Tracing decided this syscall should not happen. * We'll return a bogus call number to get an ENOSYS * error, but leave the original number in regs->gpr[0]. */ ret = -1L; + syscall_set_return_value(current, regs, -ENOSYS, 0); + } if (unlikely(test_thread_flag(TIF_SYSCALL_TRACEPOINT))) trace_sys_enter(regs, regs->gpr[0]); -- 2.1.4