From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1944) id E068E3857B9A; Fri, 5 Aug 2022 19:35:04 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org E068E3857B9A Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Szabolcs Nagy To: glibc-cvs@sourceware.org Subject: [glibc/arm/morello/main] cheri: rseq: remove const to avoid readonly permission X-Act-Checkin: glibc X-Git-Author: Szabolcs Nagy X-Git-Refname: refs/heads/arm/morello/main X-Git-Oldrev: 01faa1bcd44274b672ab75f13fd7282c9ce9656d X-Git-Newrev: 5778537ccd9a2cf46e3f4c323f84118d5a514739 Message-Id: <20220805193504.E068E3857B9A@sourceware.org> Date: Fri, 5 Aug 2022 19:35:04 +0000 (GMT) X-BeenThere: glibc-cvs@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Glibc-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 05 Aug 2022 19:35:05 -0000 https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=5778537ccd9a2cf46e3f4c323f84118d5a514739 commit 5778537ccd9a2cf46e3f4c323f84118d5a514739 Author: Szabolcs Nagy Date: Tue Mar 1 09:44:14 2022 +0000 cheri: rseq: remove const to avoid readonly permission Using const on the definition does not work for a pure capability ABI: the capability permissions when accessing the object will be read only. Use a hack to hide the public declaration in the TU where the const objects are initialized. (This should work on non-capability targets too, but to err on the safe side only enable the hack on capability targets.) Diff: --- sysdeps/nptl/dl-tls_init_tp.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/sysdeps/nptl/dl-tls_init_tp.c b/sysdeps/nptl/dl-tls_init_tp.c index 53fba774a5..e4d7bb71ad 100644 --- a/sysdeps/nptl/dl-tls_init_tp.c +++ b/sysdeps/nptl/dl-tls_init_tp.c @@ -16,6 +16,15 @@ License along with the GNU C Library; if not, see . */ +#ifdef __CHERI_PURE_CAPABILITY__ +/* This hack ensures that the later indirectly included public const + declaration does not conflict with the non-const definition here. */ +# define __rseq_size __rseq_size_public_const +# define __rseq_offset __rseq_offset_public_const +# include +# undef __rseq_size +# undef __rseq_offset +#endif #include #include #include @@ -45,8 +54,13 @@ rtld_mutex_dummy (pthread_mutex_t *lock) #endif const unsigned int __rseq_flags; +#ifdef __CHERI_PURE_CAPABILITY__ +unsigned int __rseq_size attribute_relro; +ptrdiff_t __rseq_offset attribute_relro; +#else const unsigned int __rseq_size attribute_relro; const ptrdiff_t __rseq_offset attribute_relro; +#endif void __tls_pre_init_tp (void)