Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751674AbbBRIRQ (ORCPT ); Wed, 18 Feb 2015 03:17:16 -0500 Received: from mail-bl2on0148.outbound.protection.outlook.com ([65.55.169.148]:63787 "EHLO na01-bl2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751176AbbBRIRP (ORCPT ); Wed, 18 Feb 2015 03:17:15 -0500 From: Bogdan Purcareata To: , , , CC: , , , Bogdan Purcareata Subject: [PATCH v4 1/3] powerpc: Don't force ENOSYS as error on syscall fail Date: Wed, 18 Feb 2015 08:16:51 +0000 Message-ID: <1424247413-20753-2-git-send-email-bogdan.purcareata@freescale.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1424247413-20753-1-git-send-email-bogdan.purcareata@freescale.com> References: <1424247413-20753-1-git-send-email-bogdan.purcareata@freescale.com> X-EOPAttributedMessage: 0 Authentication-Results: spf=fail (sender IP is 192.88.168.50) smtp.mailfrom=bogdan.purcareata@freescale.com; freescale.mail.onmicrosoft.com; dkim=none (message not signed) header.d=none; X-Forefront-Antispam-Report: CIP:192.88.168.50;CTRY:US;IPV:NLI;EFV:NLI;SFV:NSPM;SFS:(10019020)(6009001)(339900001)(50466002)(48376002)(76176999)(229853001)(104016003)(85426001)(92566002)(50986999)(62966003)(77156002)(77096005)(33646002)(50226001)(19580395003)(6806004)(19580405001)(2950100001)(105606002)(46102003)(575784001)(106466001)(49486002)(87936001)(2201001)(36756003)(47776003);DIR:OUT;SFP:1102;SCL:1;SRVR:BN1PR03MB187;H:tx30smr01.am.freescale.net;FPR:;SPF:Fail;MLV:sfv;LANG:en; MIME-Version: 1.0 Content-Type: text/plain X-Microsoft-Antispam: UriScan:; X-Microsoft-Antispam: BCL:0;PCL:0;RULEID:;SRVR:BN1PR03MB187; X-Microsoft-Antispam-PRVS: X-Exchange-Antispam-Report-Test: UriScan:; X-Exchange-Antispam-Report-CFA-Test: BCL:0;PCL:0;RULEID:(601004)(5005003);SRVR:BN1PR03MB187; X-Forefront-PRVS: 04916EA04C X-Exchange-Antispam-Report-CFA-Test: BCL:0;PCL:0;RULEID:;SRVR:BN1PR03MB187; X-OriginatorOrg: freescale.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 18 Feb 2015 08:17:12.2918 (UTC) X-MS-Exchange-CrossTenant-Id: 710a03f5-10f6-4d38-9ff4-a80b81da590d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=710a03f5-10f6-4d38-9ff4-a80b81da590d;Ip=[192.88.168.50] X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: BN1PR03MB187 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3487 Lines: 109 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. Delegate setting ENOSYS in case of failure, where appropriate, to do_syscall_trace_enter. v4: - update syscall_exit to be local label on 64bit, after rebasing on top of 3.19 v3: - keep setting ENOSYS in the syscall entry assembly for scenarios without syscall tracing 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 | 7 ++++++- arch/powerpc/kernel/entry_64.S | 5 +++-- arch/powerpc/kernel/ptrace.c | 4 +++- 3 files changed, 12 insertions(+), 4 deletions(-) diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S index 46fc0f4..b2f88cd 100644 --- a/arch/powerpc/kernel/entry_32.S +++ b/arch/powerpc/kernel/entry_32.S @@ -333,12 +333,12 @@ _GLOBAL(DoSyscall) lwz r11,TI_FLAGS(r10) andi. r11,r11,_TIF_SYSCALL_DOTRACE bne- syscall_dotrace -syscall_dotrace_cont: cmplwi 0,r0,NR_syscalls lis r10,sys_call_table@h ori r10,r10,sys_call_table@l slwi r0,r0,2 bge- 66f +syscall_dotrace_cont: lwzx r10,r10,r0 /* Fetch system call handler [ptr] */ mtlr r10 addi r9,r1,STACK_FRAME_OVERHEAD @@ -457,6 +457,11 @@ syscall_dotrace: lwz r7,GPR7(r1) lwz r8,GPR8(r1) REST_NVGPRS(r1) + cmplwi 0,r0,NR_syscalls + lis r10,sys_call_table@h + ori r10,r10,sys_call_table@l + slwi r0,r0,2 + bge- ret_from_syscall b syscall_dotrace_cont syscall_exit_work: diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index d180caf2..5e7434e 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -144,7 +144,6 @@ END_FW_FTR_SECTION_IFSET(FW_FEATURE_SPLPAR) ld r10,TI_FLAGS(r11) andi. r11,r10,_TIF_SYSCALL_DOTRACE bne syscall_dotrace -.Lsyscall_dotrace_cont: cmpldi 0,r0,NR_syscalls bge- syscall_enosys @@ -253,7 +252,9 @@ syscall_dotrace: addi r9,r1,STACK_FRAME_OVERHEAD CURRENT_THREAD_INFO(r10, r1) ld r10,TI_FLAGS(r10) - b .Lsyscall_dotrace_cont + cmpldi 0,r0,NR_syscalls + bge- .Lsyscall_exit + b system_call syscall_enosys: li r3,-ENOSYS diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c index f21897b..2edae06 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 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/