From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1944) id E45E83851536; Thu, 27 Oct 2022 13:56:28 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org E45E83851536 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1666878988; bh=dVUxIys8JlgiyMXE5DwSQcHV1x/WDPRgpORQcgXXrb4=; h=From:To:Subject:Date:From; b=oNeLtqwnjCYP257RtJpbRe8aVZE0nu3hcURD3vFgfiqXUX1OiNpsYygpiTluALxdL E4KI5EeWzu0NGMLUbqnJyBFiWXL3VWAiAFCQNGzETUOGrM1Mh9h/w7As3mbh1H8iA/ BQTCT62vUulC9yUSYmShL/4Hh/mAavKj31oJTmbQ= 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: 29844295c53af4dae2f88a62464a596414b4d269 X-Git-Newrev: 1865211ef5d027f10033397b8c5d46052f069cec Message-Id: <20221027135628.E45E83851536@sourceware.org> Date: Thu, 27 Oct 2022 13:56:28 +0000 (GMT) List-Id: https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=1865211ef5d027f10033397b8c5d46052f069cec commit 1865211ef5d027f10033397b8c5d46052f069cec 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)