public inbox for glibc-cvs@sourceware.org help / color / mirror / Atom feed
From: Szabolcs Nagy <nsz@sourceware.org> To: glibc-cvs@sourceware.org Subject: [glibc/arm/morello/main] cheri: don't use dl_random for pointer mangling Date: Fri, 5 Aug 2022 19:33:28 +0000 (GMT) [thread overview] Message-ID: <20220805193328.8E93B3858009@sourceware.org> (raw) https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=ff2cd89ebb434232d96b192d1a383fff543aff01 commit ff2cd89ebb434232d96b192d1a383fff543aff01 Author: Szabolcs Nagy <szabolcs.nagy@arm.com> Date: Tue Mar 1 17:36:12 2022 +0000 cheri: don't use dl_random for pointer mangling Pointer mangling cannot be supported on capability architectures. And there is not enough bytes in dl_random for 128 bit pointers. Stack guard is still loaded from dl_random: stack protection is unlikely to be useful on a capability architecture, but it works. Diff: --- sysdeps/unix/sysv/linux/dl-osinfo.h | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/sysdeps/unix/sysv/linux/dl-osinfo.h b/sysdeps/unix/sysv/linux/dl-osinfo.h index 7888915f12..b4104e0539 100644 --- a/sysdeps/unix/sysv/linux/dl-osinfo.h +++ b/sysdeps/unix/sysv/linux/dl-osinfo.h @@ -48,7 +48,12 @@ _dl_setup_stack_chk_guard (void *dl_random) static inline uintptr_t __attribute__ ((always_inline)) _dl_setup_pointer_guard (void *dl_random, uintptr_t stack_chk_guard) { +#ifdef __CHERI_PURE_CAPABILITY__ + /* Pointer mangling is not supported on capability architectures. */ + return 0; +#else uintptr_t ret; memcpy (&ret, (char *) dl_random + sizeof (ret), sizeof (ret)); return ret; +#endif }
next reply other threads:[~2022-08-05 19:33 UTC|newest] Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top 2022-08-05 19:33 Szabolcs Nagy [this message] 2022-10-26 15:16 Szabolcs Nagy 2022-10-27 13:54 Szabolcs Nagy 2022-11-23 14:44 Szabolcs Nagy
Reply instructions: You may reply publicly to this message via plain-text email using any one of the following methods: * Save the following mbox file, import it into your mail client, and reply-to-all from there: mbox Avoid top-posting and favor interleaved quoting: https://en.wikipedia.org/wiki/Posting_style#Interleaved_style * Reply using the --to, --cc, and --in-reply-to switches of git-send-email(1): git send-email \ --in-reply-to=20220805193328.8E93B3858009@sourceware.org \ --to=nsz@sourceware.org \ --cc=glibc-cvs@sourceware.org \ /path/to/YOUR_REPLY https://kernel.org/pub/software/scm/git/docs/git-send-email.html * If your mail client supports setting the In-Reply-To header via mailto: links, try the mailto: linkBe sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox; as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).