From patchwork Sun Jul 7 14:37:54 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florian Weimer X-Patchwork-Id: 1957700 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=redhat.com header.i=@redhat.com header.a=rsa-sha256 header.s=mimecast20190719 header.b=grvJAVh4; dkim-atps=neutral Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=sourceware.org (client-ip=8.43.85.97; helo=server2.sourceware.org; envelope-from=libc-alpha-bounces~incoming=patchwork.ozlabs.org@sourceware.org; receiver=patchwork.ozlabs.org) Received: from server2.sourceware.org (server2.sourceware.org [8.43.85.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (secp384r1) server-digest SHA384) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4WH8xt0304z1xr9 for ; Mon, 8 Jul 2024 00:38:25 +1000 (AEST) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id C5D6D385B505 for ; Sun, 7 Jul 2024 14:38:22 +0000 (GMT) X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by sourceware.org (Postfix) with ESMTPS id 2B05D3858CDA for ; Sun, 7 Jul 2024 14:38:04 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 2B05D3858CDA Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=redhat.com ARC-Filter: OpenARC Filter v1.0.0 sourceware.org 2B05D3858CDA Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=170.10.129.124 ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1720363087; cv=none; b=Dx3U/B1C4dGELZCB8lDGcvx3wsA1EYl4hJZj7HeH5jFMKpZyEblM4wyxlk/DMWpDBmRQ2dz1+0mWGewv33/7Msut37DBCIoNOmkqWY4InTD2ez82KhH4w5S/85MVJPLW9Ra1VARM9yjOkB9G5G4rfwUr534s4Z/+5Lil1V39byw= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1720363087; c=relaxed/simple; bh=rs7l8oMHcfmi1WB57pSzTV/4QY7p8MMu1sb+W4VjfGg=; h=DKIM-Signature:From:To:Subject:Date:Message-ID:MIME-Version; b=Mzye9e87GxF/xQrSrip3z4tSWScvspQqHdCHraFimqyyHXCbDN3VXI419dq7zALIC2EEusoe6MqF5mubI23sbZSleYujEcGRY5pbfKq42AHFXWbgYnM+gRgULAckq0NtaJWA6LhB+ryHYVJ2yj9uBnXt/KKLgaBQ5ZiJKF8/YEs= ARC-Authentication-Results: i=1; server2.sourceware.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1720363083; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type; bh=T/wBv1J78twZpAy+6U7/ceuzlMQc8Rp8rj9AnOiEu7A=; b=grvJAVh4WFSQdO7DgIfIyV2WoCxhU5awEK4BffNvrrxKyTtpbu3WduJb/uuKQP1MsVuX1P PAJxYOj79/Gowm2q5t1zmVJo5LRvmOxaBNBqly2vhW3tpJmjpoP2CYF0raNkzxEEdRLF80 tdFSuo3QA8Tex+GHMepxVFwq8CQwxck= Received: from mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-393-l_CgKw-4N4uzWHZvW_qk7A-1; Sun, 07 Jul 2024 10:38:01 -0400 X-MC-Unique: l_CgKw-4N4uzWHZvW_qk7A-1 Received: from mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.4]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-04.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 817F619560AA; Sun, 7 Jul 2024 14:38:00 +0000 (UTC) Received: from oldenburg.str.redhat.com (unknown [10.45.224.6]) by mx-prod-int-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 9794A3000181; Sun, 7 Jul 2024 14:37:57 +0000 (UTC) From: Florian Weimer To: libc-alpha@sourceware.org Cc: Michael Jeanson , Mathieu Desnoyers Subject: [PATCH] Linux: Change meaning of __rseq_size slightly Date: Sun, 07 Jul 2024 16:37:54 +0200 Message-ID: <87wmlx9sjh.fsf@oldenburg.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.4 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-Spam-Status: No, score=-10.9 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, KAM_SHORT, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H4, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.30 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: libc-alpha-bounces~incoming=patchwork.ozlabs.org@sourceware.org It is now the active area of struct rseq (so 20 initially), not the full struct size including padding at the end (32 initially). Introduce a new symbol version for __rseq_area, so that applications can rely on the new semantics. Update misc/tst-rseq to print some additional diagnostics. This replaces Michael's __rseq_feature_size patch. I prefer this approach because it avoids confusion with having three different sizes (__rseq_size, __rseq_feature_size, getauxval (AT_RSEQ_FEATURE_SIZE)). I looked at the __rseq_size usage in CRIU, and it seems to be compatible as long as the system has full ptrace support. I do not think we need a compat symbol that is artificially increased to 32. We can do this retroactively if necessary because there is a new symbol version (so that newly linked applications can depend on the new semantics). I hope we can still put this into 2.40. Tested on aarch64-linux-gnu, i386-linux-gnu, x86_64-linux-gnu. Built with build-many-glibcs.py. Thanks, Florian Reviewed-by: Mathieu Desnoyers --- NEWS | 3 +++ manual/threads.texi | 8 ++++++-- sysdeps/nptl/dl-tls_init_tp.c | 8 +------- sysdeps/unix/sysv/linux/Versions | 3 +++ sysdeps/unix/sysv/linux/aarch64/ld.abilist | 1 + sysdeps/unix/sysv/linux/alpha/ld.abilist | 1 + sysdeps/unix/sysv/linux/arc/ld.abilist | 1 + sysdeps/unix/sysv/linux/arm/be/ld.abilist | 1 + sysdeps/unix/sysv/linux/arm/le/ld.abilist | 1 + sysdeps/unix/sysv/linux/csky/ld.abilist | 1 + sysdeps/unix/sysv/linux/dl-rseq-symbols.S | 23 +++++++++++++++++++--- sysdeps/unix/sysv/linux/hppa/ld.abilist | 1 + sysdeps/unix/sysv/linux/i386/ld.abilist | 1 + sysdeps/unix/sysv/linux/loongarch/lp64/ld.abilist | 1 + sysdeps/unix/sysv/linux/m68k/coldfire/ld.abilist | 1 + sysdeps/unix/sysv/linux/m68k/m680x0/ld.abilist | 1 + sysdeps/unix/sysv/linux/microblaze/ld.abilist | 1 + sysdeps/unix/sysv/linux/mips/mips32/ld.abilist | 1 + sysdeps/unix/sysv/linux/mips/mips64/n32/ld.abilist | 1 + sysdeps/unix/sysv/linux/mips/mips64/n64/ld.abilist | 1 + sysdeps/unix/sysv/linux/nios2/ld.abilist | 1 + sysdeps/unix/sysv/linux/or1k/ld.abilist | 1 + .../unix/sysv/linux/powerpc/powerpc32/ld.abilist | 1 + .../sysv/linux/powerpc/powerpc64/be/ld.abilist | 1 + .../sysv/linux/powerpc/powerpc64/le/ld.abilist | 1 + sysdeps/unix/sysv/linux/riscv/rv32/ld.abilist | 1 + sysdeps/unix/sysv/linux/riscv/rv64/ld.abilist | 1 + sysdeps/unix/sysv/linux/rseq-internal.h | 23 ++++++++++++++++++++-- sysdeps/unix/sysv/linux/s390/s390-32/ld.abilist | 1 + sysdeps/unix/sysv/linux/s390/s390-64/ld.abilist | 1 + sysdeps/unix/sysv/linux/sh/be/ld.abilist | 1 + sysdeps/unix/sysv/linux/sh/le/ld.abilist | 1 + sysdeps/unix/sysv/linux/sparc/sparc32/ld.abilist | 1 + sysdeps/unix/sysv/linux/sparc/sparc64/ld.abilist | 1 + sysdeps/unix/sysv/linux/tst-rseq.c | 10 +++++++++- sysdeps/unix/sysv/linux/x86_64/64/ld.abilist | 1 + sysdeps/unix/sysv/linux/x86_64/x32/ld.abilist | 1 + 37 files changed, 93 insertions(+), 15 deletions(-) base-commit: 9fc639f654dc004736836613be703e6bed0c36a8 diff --git a/NEWS b/NEWS index f626896aa0..3824815917 100644 --- a/NEWS +++ b/NEWS @@ -49,6 +49,9 @@ Deprecated and removed features, and other changes affecting compatibility: (except for login_tty) due to locking and session management problems. +* __rseq_size now denotes the size of the active rseq area (20 bytes + initially), not the size of struct rseq (32 bytes initially). + Changes to build and runtime requirements: [Add changes to build and runtime requirements here] diff --git a/manual/threads.texi b/manual/threads.texi index e5544ff3da..25e99c9606 100644 --- a/manual/threads.texi +++ b/manual/threads.texi @@ -1007,8 +1007,12 @@ This variable is either zero (if restartable sequence registration failed or has been disabled) or the size of the restartable sequence registration. This can be different from the size of @code{struct rseq} if the kernel has extended the size of the registration. If -registration is successful, @code{__rseq_size} is at least 32 (the -initial size of @code{struct rseq}). +registration is successful, @code{__rseq_size} is at least 20 (the +initially active size of @code{struct rseq}). + +Previous versions of @theglibc{} set this to 32 even if the kernel only +supported the initial area of 20 bytes because the value included unused +padding at the end of the restartable sequence area. @end deftypevar @deftypevar {unsigned int} __rseq_flags diff --git a/sysdeps/nptl/dl-tls_init_tp.c b/sysdeps/nptl/dl-tls_init_tp.c index 7eb35fb133..7803e19fd1 100644 --- a/sysdeps/nptl/dl-tls_init_tp.c +++ b/sysdeps/nptl/dl-tls_init_tp.c @@ -46,10 +46,6 @@ rtld_mutex_dummy (pthread_mutex_t *lock) const unsigned int __rseq_flags; -/* The variables are in .data.relro but are not yet write-protected. */ -extern unsigned int _rseq_size attribute_hidden; -extern ptrdiff_t _rseq_offset attribute_hidden; - void __tls_pre_init_tp (void) { @@ -106,9 +102,7 @@ __tls_init_tp (void) bool do_rseq = true; do_rseq = TUNABLE_GET (rseq, int, NULL); if (rseq_register_current_thread (pd, do_rseq)) - { - _rseq_size = sizeof (pd->rseq_area); - } + _rseq_size = RSEQ_AREA_SIZE_INITIAL_USED; #ifdef RSEQ_SIG /* This should be a compile-time constant, but the current diff --git a/sysdeps/unix/sysv/linux/Versions b/sysdeps/unix/sysv/linux/Versions index 268ba1b6ac..e3b232db92 100644 --- a/sysdeps/unix/sysv/linux/Versions +++ b/sysdeps/unix/sysv/linux/Versions @@ -356,6 +356,9 @@ ld { __rseq_offset; __rseq_size; } + GLIBC_2.40 { + __rseq_size; + } GLIBC_PRIVATE { __nptl_change_stack_perm; } diff --git a/sysdeps/unix/sysv/linux/aarch64/ld.abilist b/sysdeps/unix/sysv/linux/aarch64/ld.abilist index 5151c0781d..04efaa1e4f 100644 --- a/sysdeps/unix/sysv/linux/aarch64/ld.abilist +++ b/sysdeps/unix/sysv/linux/aarch64/ld.abilist @@ -7,3 +7,4 @@ GLIBC_2.34 __rtld_version_placeholder F GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x8 GLIBC_2.35 __rseq_size D 0x4 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/alpha/ld.abilist b/sysdeps/unix/sysv/linux/alpha/ld.abilist index 3e296c5473..9103538e04 100644 --- a/sysdeps/unix/sysv/linux/alpha/ld.abilist +++ b/sysdeps/unix/sysv/linux/alpha/ld.abilist @@ -7,3 +7,4 @@ GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x8 GLIBC_2.35 __rseq_size D 0x4 GLIBC_2.4 __stack_chk_guard D 0x8 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/arc/ld.abilist b/sysdeps/unix/sysv/linux/arc/ld.abilist index 55f0c2ab9c..031a0b5e33 100644 --- a/sysdeps/unix/sysv/linux/arc/ld.abilist +++ b/sysdeps/unix/sysv/linux/arc/ld.abilist @@ -7,3 +7,4 @@ GLIBC_2.34 __rtld_version_placeholder F GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x4 GLIBC_2.35 __rseq_size D 0x4 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/arm/be/ld.abilist b/sysdeps/unix/sysv/linux/arm/be/ld.abilist index f1da2c636d..4ee96084c1 100644 --- a/sysdeps/unix/sysv/linux/arm/be/ld.abilist +++ b/sysdeps/unix/sysv/linux/arm/be/ld.abilist @@ -7,3 +7,4 @@ GLIBC_2.4 __stack_chk_guard D 0x4 GLIBC_2.4 __tls_get_addr F GLIBC_2.4 _dl_mcount F GLIBC_2.4 _r_debug D 0x14 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/arm/le/ld.abilist b/sysdeps/unix/sysv/linux/arm/le/ld.abilist index f1da2c636d..4ee96084c1 100644 --- a/sysdeps/unix/sysv/linux/arm/le/ld.abilist +++ b/sysdeps/unix/sysv/linux/arm/le/ld.abilist @@ -7,3 +7,4 @@ GLIBC_2.4 __stack_chk_guard D 0x4 GLIBC_2.4 __tls_get_addr F GLIBC_2.4 _dl_mcount F GLIBC_2.4 _r_debug D 0x14 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/csky/ld.abilist b/sysdeps/unix/sysv/linux/csky/ld.abilist index 7f482276ed..ac51f7ca61 100644 --- a/sysdeps/unix/sysv/linux/csky/ld.abilist +++ b/sysdeps/unix/sysv/linux/csky/ld.abilist @@ -7,3 +7,4 @@ GLIBC_2.34 __rtld_version_placeholder F GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x4 GLIBC_2.35 __rseq_size D 0x4 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/dl-rseq-symbols.S b/sysdeps/unix/sysv/linux/dl-rseq-symbols.S index b4bba06a99..2155a79e02 100644 --- a/sysdeps/unix/sysv/linux/dl-rseq-symbols.S +++ b/sysdeps/unix/sysv/linux/dl-rseq-symbols.S @@ -17,6 +17,7 @@ . */ #include +#include #if __WORDSIZE == 64 #define RSEQ_OFFSET_SIZE 8 @@ -32,18 +33,34 @@ dynamic linker which will initialize the value both symbols point to before copy relocations take place. */ - .globl __rseq_size - .type __rseq_size, %object - .size __rseq_size, 4 .hidden _rseq_size .globl _rseq_size .type _rseq_size, %object .size _rseq_size, 4 +#ifdef SHARED + .globl __rseq_size_original + .type __rseq_size_original, %object + .size __rseq_size_original, 4 + .globl __rseq_size_current + .type __rseq_size_current, %object + .size __rseq_size_current, 4 +#else + .globl __rseq_size + .type __rseq_size, %object + .size __rseq_size, 4 +#endif .section .data.rel.ro .balign 4 __rseq_size: +__rseq_size_original: +__rseq_size_current: _rseq_size: .zero 4 +#ifdef SHARED +/* Ensure that new binaries get the new __rseq_size semantics. */ +compat_symbol (ld, __rseq_size_original, __rseq_size, GLIBC_2_35) +versioned_symbol (ld, __rseq_size_current, __rseq_size, GLIBC_2_40) +#endif /* Define 2 symbols: '__rseq_offset' is public const and '_rseq_offset' (an alias of '__rseq_offset') is hidden and writable for internal use by the diff --git a/sysdeps/unix/sysv/linux/hppa/ld.abilist b/sysdeps/unix/sysv/linux/hppa/ld.abilist index 7f5527fb30..a23ea40dff 100644 --- a/sysdeps/unix/sysv/linux/hppa/ld.abilist +++ b/sysdeps/unix/sysv/linux/hppa/ld.abilist @@ -7,3 +7,4 @@ GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x4 GLIBC_2.35 __rseq_size D 0x4 GLIBC_2.4 __stack_chk_guard D 0x4 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/i386/ld.abilist b/sysdeps/unix/sysv/linux/i386/ld.abilist index 9c4a45d8dc..6041d6473c 100644 --- a/sysdeps/unix/sysv/linux/i386/ld.abilist +++ b/sysdeps/unix/sysv/linux/i386/ld.abilist @@ -7,3 +7,4 @@ GLIBC_2.34 __rtld_version_placeholder F GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x4 GLIBC_2.35 __rseq_size D 0x4 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/loongarch/lp64/ld.abilist b/sysdeps/unix/sysv/linux/loongarch/lp64/ld.abilist index 93fcd64eee..bf7fb6b1fd 100644 --- a/sysdeps/unix/sysv/linux/loongarch/lp64/ld.abilist +++ b/sysdeps/unix/sysv/linux/loongarch/lp64/ld.abilist @@ -6,3 +6,4 @@ GLIBC_2.36 __stack_chk_guard D 0x8 GLIBC_2.36 __tls_get_addr F GLIBC_2.36 _dl_mcount F GLIBC_2.36 _r_debug D 0x28 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/m68k/coldfire/ld.abilist b/sysdeps/unix/sysv/linux/m68k/coldfire/ld.abilist index f1da2c636d..4ee96084c1 100644 --- a/sysdeps/unix/sysv/linux/m68k/coldfire/ld.abilist +++ b/sysdeps/unix/sysv/linux/m68k/coldfire/ld.abilist @@ -7,3 +7,4 @@ GLIBC_2.4 __stack_chk_guard D 0x4 GLIBC_2.4 __tls_get_addr F GLIBC_2.4 _dl_mcount F GLIBC_2.4 _r_debug D 0x14 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/m68k/m680x0/ld.abilist b/sysdeps/unix/sysv/linux/m68k/m680x0/ld.abilist index dadbf852d0..526c0d5fba 100644 --- a/sysdeps/unix/sysv/linux/m68k/m680x0/ld.abilist +++ b/sysdeps/unix/sysv/linux/m68k/m680x0/ld.abilist @@ -7,3 +7,4 @@ GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x4 GLIBC_2.35 __rseq_size D 0x4 GLIBC_2.4 __stack_chk_guard D 0x4 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/microblaze/ld.abilist b/sysdeps/unix/sysv/linux/microblaze/ld.abilist index 89a0b7e4fd..e57cec648d 100644 --- a/sysdeps/unix/sysv/linux/microblaze/ld.abilist +++ b/sysdeps/unix/sysv/linux/microblaze/ld.abilist @@ -7,3 +7,4 @@ GLIBC_2.34 __rtld_version_placeholder F GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x4 GLIBC_2.35 __rseq_size D 0x4 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/mips/mips32/ld.abilist b/sysdeps/unix/sysv/linux/mips/mips32/ld.abilist index e304d1bb46..9033f384d5 100644 --- a/sysdeps/unix/sysv/linux/mips/mips32/ld.abilist +++ b/sysdeps/unix/sysv/linux/mips/mips32/ld.abilist @@ -7,3 +7,4 @@ GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x4 GLIBC_2.35 __rseq_size D 0x4 GLIBC_2.4 __stack_chk_guard D 0x4 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/ld.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n32/ld.abilist index e304d1bb46..9033f384d5 100644 --- a/sysdeps/unix/sysv/linux/mips/mips64/n32/ld.abilist +++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/ld.abilist @@ -7,3 +7,4 @@ GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x4 GLIBC_2.35 __rseq_size D 0x4 GLIBC_2.4 __stack_chk_guard D 0x4 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n64/ld.abilist b/sysdeps/unix/sysv/linux/mips/mips64/n64/ld.abilist index f26e594a13..bf037e137a 100644 --- a/sysdeps/unix/sysv/linux/mips/mips64/n64/ld.abilist +++ b/sysdeps/unix/sysv/linux/mips/mips64/n64/ld.abilist @@ -7,3 +7,4 @@ GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x8 GLIBC_2.35 __rseq_size D 0x4 GLIBC_2.4 __stack_chk_guard D 0x8 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/nios2/ld.abilist b/sysdeps/unix/sysv/linux/nios2/ld.abilist index 811ae9da2f..127829e91c 100644 --- a/sysdeps/unix/sysv/linux/nios2/ld.abilist +++ b/sysdeps/unix/sysv/linux/nios2/ld.abilist @@ -7,3 +7,4 @@ GLIBC_2.34 __rtld_version_placeholder F GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x4 GLIBC_2.35 __rseq_size D 0x4 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/or1k/ld.abilist b/sysdeps/unix/sysv/linux/or1k/ld.abilist index cff2ffd23b..55baff19f3 100644 --- a/sysdeps/unix/sysv/linux/or1k/ld.abilist +++ b/sysdeps/unix/sysv/linux/or1k/ld.abilist @@ -6,3 +6,4 @@ GLIBC_2.35 __stack_chk_guard D 0x4 GLIBC_2.35 __tls_get_addr F GLIBC_2.35 _dl_mcount F GLIBC_2.35 _r_debug D 0x14 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc32/ld.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc32/ld.abilist index b1073f0942..46b193e2ef 100644 --- a/sysdeps/unix/sysv/linux/powerpc/powerpc32/ld.abilist +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc32/ld.abilist @@ -9,3 +9,4 @@ GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x4 GLIBC_2.35 __rseq_size D 0x4 GLIBC_2.39 __parse_hwcap_3_4_and_convert_at_platform F +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/ld.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/ld.abilist index 40942a2cc6..e8a9859d9a 100644 --- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/ld.abilist +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/be/ld.abilist @@ -9,3 +9,4 @@ GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x8 GLIBC_2.35 __rseq_size D 0x4 GLIBC_2.39 __parse_hwcap_3_4_and_convert_at_platform F +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/ld.abilist b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/ld.abilist index 01f2694a4d..e57d8e3331 100644 --- a/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/ld.abilist +++ b/sysdeps/unix/sysv/linux/powerpc/powerpc64/le/ld.abilist @@ -9,3 +9,4 @@ GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x8 GLIBC_2.35 __rseq_size D 0x4 GLIBC_2.39 __parse_hwcap_3_4_and_convert_at_platform F +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/riscv/rv32/ld.abilist b/sysdeps/unix/sysv/linux/riscv/rv32/ld.abilist index 068368878e..d9e51f124c 100644 --- a/sysdeps/unix/sysv/linux/riscv/rv32/ld.abilist +++ b/sysdeps/unix/sysv/linux/riscv/rv32/ld.abilist @@ -7,3 +7,4 @@ GLIBC_2.34 __rtld_version_placeholder F GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x4 GLIBC_2.35 __rseq_size D 0x4 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/riscv/rv64/ld.abilist b/sysdeps/unix/sysv/linux/riscv/rv64/ld.abilist index a7758a0e52..ff2294932c 100644 --- a/sysdeps/unix/sysv/linux/riscv/rv64/ld.abilist +++ b/sysdeps/unix/sysv/linux/riscv/rv64/ld.abilist @@ -7,3 +7,4 @@ GLIBC_2.34 __rtld_version_placeholder F GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x8 GLIBC_2.35 __rseq_size D 0x4 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/rseq-internal.h b/sysdeps/unix/sysv/linux/rseq-internal.h index 48eebc1e16..7ea935b4ad 100644 --- a/sysdeps/unix/sysv/linux/rseq-internal.h +++ b/sysdeps/unix/sysv/linux/rseq-internal.h @@ -25,15 +25,34 @@ #include #include +/* 32 is the initially required value for the area size. The + actually used rseq size may be less (20 bytes initially). */ +#define RSEQ_AREA_SIZE_INITIAL 32 +#define RSEQ_AREA_SIZE_INITIAL_USED 20 + +/* The variables are in .data.relro but are not yet write-protected. */ +extern unsigned int _rseq_size attribute_hidden; +extern ptrdiff_t _rseq_offset attribute_hidden; + #ifdef RSEQ_SIG static inline bool rseq_register_current_thread (struct pthread *self, bool do_rseq) { if (do_rseq) { + unsigned int size; +#if IS_IN (rtld) + /* Use the hidden symbol in ld.so. */ + size = _rseq_size; +#else + size = __rseq_size; +#endif + if (size < RSEQ_AREA_SIZE_INITIAL) + /* The initial implementation used only 20 bytes out of 32, + but still expected size 32. */ + size = RSEQ_AREA_SIZE_INITIAL; int ret = INTERNAL_SYSCALL_CALL (rseq, &self->rseq_area, - sizeof (self->rseq_area), - 0, RSEQ_SIG); + size, 0, RSEQ_SIG); if (!INTERNAL_SYSCALL_ERROR_P (ret)) return true; } diff --git a/sysdeps/unix/sysv/linux/s390/s390-32/ld.abilist b/sysdeps/unix/sysv/linux/s390/s390-32/ld.abilist index c15288394a..b8b8e0dd30 100644 --- a/sysdeps/unix/sysv/linux/s390/s390-32/ld.abilist +++ b/sysdeps/unix/sysv/linux/s390/s390-32/ld.abilist @@ -6,3 +6,4 @@ GLIBC_2.34 __rtld_version_placeholder F GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x4 GLIBC_2.35 __rseq_size D 0x4 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/s390/s390-64/ld.abilist b/sysdeps/unix/sysv/linux/s390/s390-64/ld.abilist index 78d071600b..b436ecbdf5 100644 --- a/sysdeps/unix/sysv/linux/s390/s390-64/ld.abilist +++ b/sysdeps/unix/sysv/linux/s390/s390-64/ld.abilist @@ -6,3 +6,4 @@ GLIBC_2.34 __rtld_version_placeholder F GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x8 GLIBC_2.35 __rseq_size D 0x4 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/sh/be/ld.abilist b/sysdeps/unix/sysv/linux/sh/be/ld.abilist index 7f5527fb30..a23ea40dff 100644 --- a/sysdeps/unix/sysv/linux/sh/be/ld.abilist +++ b/sysdeps/unix/sysv/linux/sh/be/ld.abilist @@ -7,3 +7,4 @@ GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x4 GLIBC_2.35 __rseq_size D 0x4 GLIBC_2.4 __stack_chk_guard D 0x4 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/sh/le/ld.abilist b/sysdeps/unix/sysv/linux/sh/le/ld.abilist index 7f5527fb30..a23ea40dff 100644 --- a/sysdeps/unix/sysv/linux/sh/le/ld.abilist +++ b/sysdeps/unix/sysv/linux/sh/le/ld.abilist @@ -7,3 +7,4 @@ GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x4 GLIBC_2.35 __rseq_size D 0x4 GLIBC_2.4 __stack_chk_guard D 0x4 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/sparc/sparc32/ld.abilist b/sysdeps/unix/sysv/linux/sparc/sparc32/ld.abilist index 3aac73f3df..1ea464b376 100644 --- a/sysdeps/unix/sysv/linux/sparc/sparc32/ld.abilist +++ b/sysdeps/unix/sysv/linux/sparc/sparc32/ld.abilist @@ -6,3 +6,4 @@ GLIBC_2.34 __rtld_version_placeholder F GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x4 GLIBC_2.35 __rseq_size D 0x4 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/sparc/sparc64/ld.abilist b/sysdeps/unix/sysv/linux/sparc/sparc64/ld.abilist index 5471b24d59..94ff921440 100644 --- a/sysdeps/unix/sysv/linux/sparc/sparc64/ld.abilist +++ b/sysdeps/unix/sysv/linux/sparc/sparc64/ld.abilist @@ -6,3 +6,4 @@ GLIBC_2.34 __rtld_version_placeholder F GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x8 GLIBC_2.35 __rseq_size D 0x4 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/tst-rseq.c b/sysdeps/unix/sysv/linux/tst-rseq.c index 2c90409ba0..08a9533130 100644 --- a/sysdeps/unix/sysv/linux/tst-rseq.c +++ b/sysdeps/unix/sysv/linux/tst-rseq.c @@ -29,6 +29,7 @@ # include # include # include +# include # include # include # include "tst-rseq.h" @@ -42,7 +43,8 @@ do_rseq_main_test (void) TEST_COMPARE (__rseq_flags, 0); TEST_VERIFY ((char *) __thread_pointer () + __rseq_offset == (char *) &pd->rseq_area); - TEST_COMPARE (__rseq_size, sizeof (pd->rseq_area)); + /* The current implementation only supports the initial size. */ + TEST_COMPARE (__rseq_size, 20); } static void @@ -52,6 +54,12 @@ do_rseq_test (void) { FAIL_UNSUPPORTED ("kernel does not support rseq, skipping test"); } + printf ("info: __rseq_size: %u\n", __rseq_size); + printf ("info: __rseq_offset: %td\n", __rseq_offset); + printf ("info: __rseq_flags: %u\n", __rseq_flags); + printf ("info: getauxval (AT_RSEQ_FEATURE_SIZE): %ld\n", + getauxval (AT_RSEQ_FEATURE_SIZE)); + printf ("info: getauxval (AT_RSEQ_ALIGN): %ld\n", getauxval (AT_RSEQ_ALIGN)); do_rseq_main_test (); } #else /* RSEQ_SIG */ diff --git a/sysdeps/unix/sysv/linux/x86_64/64/ld.abilist b/sysdeps/unix/sysv/linux/x86_64/64/ld.abilist index 5a8bd322cd..171b38a2b9 100644 --- a/sysdeps/unix/sysv/linux/x86_64/64/ld.abilist +++ b/sysdeps/unix/sysv/linux/x86_64/64/ld.abilist @@ -6,3 +6,4 @@ GLIBC_2.34 __rtld_version_placeholder F GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x8 GLIBC_2.35 __rseq_size D 0x4 +GLIBC_2.40 __rseq_size D 0x4 diff --git a/sysdeps/unix/sysv/linux/x86_64/x32/ld.abilist b/sysdeps/unix/sysv/linux/x86_64/x32/ld.abilist index e17496d124..0a18a6c2d6 100644 --- a/sysdeps/unix/sysv/linux/x86_64/x32/ld.abilist +++ b/sysdeps/unix/sysv/linux/x86_64/x32/ld.abilist @@ -6,3 +6,4 @@ GLIBC_2.34 __rtld_version_placeholder F GLIBC_2.35 __rseq_flags D 0x4 GLIBC_2.35 __rseq_offset D 0x4 GLIBC_2.35 __rseq_size D 0x4 +GLIBC_2.40 __rseq_size D 0x4