From patchwork Fri Apr 3 20:31:52 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Adhemerval Zanella Netto X-Patchwork-Id: 38737 Return-Path: X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from mail-qk1-x744.google.com (mail-qk1-x744.google.com [IPv6:2607:f8b0:4864:20::744]) by sourceware.org (Postfix) with ESMTPS id 3EA52388A02A for ; Fri, 3 Apr 2020 20:32:27 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 3EA52388A02A Received: by mail-qk1-x744.google.com with SMTP id o18so6697021qko.12 for ; Fri, 03 Apr 2020 13:32:27 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:subject:date:message-id:in-reply-to :references; bh=dKY3ayiiRjY22u/V2yYMSApKmTGrheCqCVARFrzB51o=; b=QDvYksEJ9zCuBHCvNqzBgaNTiFH1Wd4oo0U7/+pBfJxgF8Ux16nPDCcKgbZvhDrMzg 9+Pt1FD7OhXyry9GsRhsLOTCQV4zA6TzbDRQGzZ0hOtz5zGSWAJP7ZNIF3qv6NMV16XN DoLPfPyrjvLjWzr38AiN/Fb4ULMZmiTsegdMnxVrrgNx+1xo39TvXeEBtF1NpcqyQfU+ Q6/DspNmJJxT5QJzGGRyAT+k43C7h/zCb9GnXrsXRS2ist0ZYa4a4JhCoJvWaWjGDfYL FkwuEScFVpp0Vj8rFLrOLkWQxB/f5HSW9wyHtf0+gTuXQB84bjWR3uYIWRsr6068BWP3 hSCg== X-Gm-Message-State: AGi0PuYnZu1TUhtDrX9MaOPWzxKLAQgpyVUuXLBx6ejYhdNE/v20Q0To gXStITpu9kiphtdJP7tYilDte8oJ1jY= X-Google-Smtp-Source: APiQypJSW9KIAsIT+LiiemjWw798+BCR1b935GWS+Cx08EpSLhh5Cihr3wqaR04RU1Jrp5lTIjsKzA== X-Received: by 2002:a37:9cd:: with SMTP id 196mr4415256qkj.44.1585945946280; Fri, 03 Apr 2020 13:32:26 -0700 (PDT) Received: from localhost.localdomain ([177.194.48.209]) by smtp.googlemail.com with ESMTPSA id d141sm7063535qke.68.2020.04.03.13.32.24 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 03 Apr 2020 13:32:25 -0700 (PDT) From: Adhemerval Zanella To: libc-alpha@sourceware.org Subject: [PATCH v4 12/21] nptl: sparc: Fix Race conditions in pthread cancellation [BZ#12683] Date: Fri, 3 Apr 2020 17:31:52 -0300 Message-Id: <20200403203201.7494-13-adhemerval.zanella@linaro.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20200403203201.7494-1-adhemerval.zanella@linaro.org> References: <20200403203201.7494-1-adhemerval.zanella@linaro.org> X-Spam-Status: No, score=-26.6 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_SHORT, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 03 Apr 2020 20:32:29 -0000 This patch adds the sparc modifications required for the BZ#12683 fix. Different than other architectures, SPARC passes the sigcontext_t struct pointer as third argument in the signal handler set with SA_SIGINFO (some info at [1]) for 64 bits and the pt_regs in 32 bits. >From Linux code: * arch/sparc/kernel/signal_64.c 428 /* 3. signal handler back-trampoline and parameters */ 429 regs->u_regs[UREG_FP] = ((unsigned long) sf) - STACK_BIAS; 430 regs->u_regs[UREG_I0] = ksig->sig; 431 regs->u_regs[UREG_I1] = (unsigned long) &sf->info; 432 433 /* The sigcontext is passed in this way because of how it 434 * is defined in GLIBC's /usr/include/bits/sigcontext.h 435 * for sparc64. It includes the 128 bytes of siginfo_t. 436 */ 437 regs->u_regs[UREG_I2] = (unsigned long) &sf->info; * arch/sparc/kernel/signal_32.c: 392 regs->u_regs[UREG_FP] = (unsigned long) sf; 393 regs->u_regs[UREG_I0] = ksig->sig; 394 regs->u_regs[UREG_I1] = (unsigned long) &sf->info; 395 regs->u_regs[UREG_I2] = (unsigned long) &sf->regs; 396 397 regs->pc = (unsigned long) ksig->ka.sa.sa_handler; 398 regs->npc = (regs->pc + 4); So it requires an arch-specific ucontext_add_cancel. Also on sparc interrupted pause syscall returns with a PC indicating a side-effect and this deviates from other architectures. The sparc64 pause fall back to ppool syscall. Checked on sparc64-linux-gnu and sparcv9-linux-gnu. [1] https://www.spinics.net/lists/sparclinux/msg05037.html --- sysdeps/sparc/nptl/tcb-offsets.sym | 3 + .../sysv/linux/sparc/cancellation-sigmask.h | 39 ++++++++++ .../sysv/linux/sparc/sparc32/syscall_cancel.S | 71 ++++++++++++++++++ sysdeps/unix/sysv/linux/sparc/sparc64/pause.c | 25 +++++++ .../sysv/linux/sparc/sparc64/syscall_cancel.S | 74 +++++++++++++++++++ 5 files changed, 212 insertions(+) create mode 100644 sysdeps/unix/sysv/linux/sparc/cancellation-sigmask.h create mode 100644 sysdeps/unix/sysv/linux/sparc/sparc32/syscall_cancel.S create mode 100644 sysdeps/unix/sysv/linux/sparc/sparc64/pause.c create mode 100644 sysdeps/unix/sysv/linux/sparc/sparc64/syscall_cancel.S diff --git a/sysdeps/sparc/nptl/tcb-offsets.sym b/sysdeps/sparc/nptl/tcb-offsets.sym index f75d02065e..8112290d88 100644 --- a/sysdeps/sparc/nptl/tcb-offsets.sym +++ b/sysdeps/sparc/nptl/tcb-offsets.sym @@ -4,3 +4,6 @@ MULTIPLE_THREADS_OFFSET offsetof (tcbhead_t, multiple_threads) POINTER_GUARD offsetof (tcbhead_t, pointer_guard) TID offsetof (struct pthread, tid) + +-- Not strictly offsets, used on syscall_cancel.S +TCB_CANCELED_BITMASK CANCELED_BITMASK diff --git a/sysdeps/unix/sysv/linux/sparc/cancellation-sigmask.h b/sysdeps/unix/sysv/linux/sparc/cancellation-sigmask.h new file mode 100644 index 0000000000..8086228828 --- /dev/null +++ b/sysdeps/unix/sysv/linux/sparc/cancellation-sigmask.h @@ -0,0 +1,39 @@ +/* Architecture specific bits for cancellation handling. + Copyright (C) 2020 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef _NPTL_CANCELLATION_SIGMASK_H +#define _NPTL_CANCELLATION_SIGMASK_H 1 + +/* Add the SIGCANCEL signal on sigmask set at the ucontext CTX obtained from + the sigaction handler. */ +static void +ucontext_block_sigcancel (void *ctx) +{ + sigset_t *set; +#ifdef __arch64__ + struct pt_regs *regs = (struct pt_regs*) ((siginfo_t *)(ctx) + 1); + __siginfo_fpu_t *f = (__siginfo_fpu_t *)(regs + 1); + set = (sigset_t *) ((stack_t *)(f + 1) + 1); +#else + struct pt_regs32 *ptregs = (struct pt_regs32 *) (ctx); + set = (sigset_t *) (ptregs + 1); +#endif + __sigaddset (set, SIGCANCEL); +} + +#endif diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/syscall_cancel.S b/sysdeps/unix/sysv/linux/sparc/sparc32/syscall_cancel.S new file mode 100644 index 0000000000..2393bf9be0 --- /dev/null +++ b/sysdeps/unix/sysv/linux/sparc/sparc32/syscall_cancel.S @@ -0,0 +1,71 @@ +/* Cancellable syscall wrapper. Linux/sparc32 version. + Copyright (C) 2020 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include + +/* long int __syscall_cancel_arch (int *cancelhandling, + long int nr, + long int arg1, + long int arg2, + long int arg3, + long int arg4, + long int arg5, + long int arg6) */ + +ENTRY (__syscall_cancel_arch) + save %sp, -96, %sp + + cfi_window_save + cfi_register (%o7, %i7) + cfi_def_cfa_register (%fp) + + .globl __syscall_cancel_arch_start +__syscall_cancel_arch_start: + + /* if (*cancelhandling & CANCELED_BITMASK) + __syscall_do_cancel() */ + ld [%i0], %g2 + andcc %g2, TCB_CANCELED_BITMASK, %g0 + bne,pn %icc, 2f + /* Issue a 6 argument syscall. */ + mov %i1, %g1 + mov %i2, %o0 + mov %i3, %o1 + mov %i4, %o2 + mov %i5, %o3 + ld [%fp+92], %o4 + ld [%fp+96], %o5 + ta 0x10 + + .globl __syscall_cancel_arch_end +__syscall_cancel_arch_end: + bcc 1f + nop + sub %g0, %o0, %o0 +1: + mov %o0, %i0 + return %i7+8 + nop + +2: + call __syscall_do_cancel, 0 + nop + nop + +END (__syscall_cancel_arch) +libc_hidden_def (__syscall_cancel_arch) diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/pause.c b/sysdeps/unix/sysv/linux/sparc/sparc64/pause.c new file mode 100644 index 0000000000..4fae573091 --- /dev/null +++ b/sysdeps/unix/sysv/linux/sparc/sparc64/pause.c @@ -0,0 +1,25 @@ +/* Linux pause syscall implementation. Linux/sparc64. + Copyright (C) 2020 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include + +/* On sparc interrupted pause syscall returns with a PC indicating a + side-effect and this deviates from other architectures. Fall back to + ppool implementation. */ +#undef __NR_pause +#include diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/syscall_cancel.S b/sysdeps/unix/sysv/linux/sparc/sparc64/syscall_cancel.S new file mode 100644 index 0000000000..f9ecb4a851 --- /dev/null +++ b/sysdeps/unix/sysv/linux/sparc/sparc64/syscall_cancel.S @@ -0,0 +1,74 @@ +/* Cancellable syscall wrapper. Linux/sparc64 version. + Copyright (C) 2020 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include + + .register %g2, #scratch + +/* long int __syscall_cancel_arch (int *cancelhandling, + long int nr, + long int arg1, + long int arg2, + long int arg3, + long int arg4, + long int arg5, + long int arg6) */ + +ENTRY (__syscall_cancel_arch) + save %sp, -176, %sp + + cfi_window_save + cfi_register (%o7, %i7) + cfi_def_cfa_register (%fp) + + .globl __syscall_cancel_arch_start +__syscall_cancel_arch_start: + + /* if (*cancelhandling & CANCELED_BITMASK) + __syscall_do_cancel() */ + lduw [%i0], %g2 + andcc %g2, TCB_CANCELED_BITMASK, %g0 + bne,pn %xcc, 2f + /* Issue a 6 argument syscall. */ + mov %i1, %g1 + mov %i2, %o0 + mov %i3, %o1 + mov %i4, %o2 + mov %i5, %o3 + ldx [%fp + STACK_BIAS + 176], %o4 + ldx [%fp + STACK_BIAS + 184], %o5 + ta 0x6d + + .global __syscall_cancel_arch_end +__syscall_cancel_arch_end: + + bcc,pt %xcc, 1f + nop + sub %g0, %o0, %o0 +1: + mov %o0, %i0 + return %i7+8 + nop + +2: + call __syscall_do_cancel, 0 + nop + nop + +END (__syscall_cancel_arch) +libc_hidden_def (__syscall_cancel_arch)