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From: Szabolcs Nagy <>
Subject: [glibc/arm/morello/main] cheri: don't use dl_random for pointer mangling
Date: Thu, 27 Oct 2022 13:54:49 +0000 (GMT)	[thread overview]
Message-ID: <> (raw);h=8fc31e80652b073dfad49a57f925663db8d618eb

commit 8fc31e80652b073dfad49a57f925663db8d618eb
Author: Szabolcs Nagy <>
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.

 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 49d8f973c8..c5d864f5ba 100644
--- a/sysdeps/unix/sysv/linux/dl-osinfo.h
+++ b/sysdeps/unix/sysv/linux/dl-osinfo.h
@@ -52,7 +52,12 @@ _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)
+  /* Pointer mangling is not supported on capability architectures.  */
+  return 0;
   uintptr_t ret;
   memcpy (&ret, (char *) dl_random + sizeof (ret), sizeof (ret));
   return ret;

             reply	other threads:[~2022-10-27 13:54 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-10-27 13:54 Szabolcs Nagy [this message]
  -- strict thread matches above, loose matches on Subject: below --
2022-11-23 14:44 Szabolcs Nagy
2022-10-26 15:16 Szabolcs Nagy
2022-08-05 19:33 Szabolcs Nagy

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