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| From | Lawrence D'Oliveiro <ldo@nz.invalid> |
|---|---|
| Newsgroups | comp.os.linux.misc |
| Subject | Re: VMS |
| Date | 2025-08-02 00:01 +0000 |
| Organization | A noiseless patient Spider |
| Message-ID | <106jkgv$nd9d$4@dont-email.me> (permalink) |
| References | (22 earlier) <1064r6l$2s0gs$2@dont-email.me> <10651hc$1qlv3$6@dont-email.me> <10667la$35rkf$3@dont-email.me> <688d11dc$0$10593$426a74cc@news.free.fr> <106j8ke$ipce$1@dont-email.me> |
On Fri, 1 Aug 2025 20:38:38 -0000 (UTC), Lew Pitcher wrote:
> After a while, though, IBM /changed/ IEFBR14. MVS required a
> returncode in register 15. Up until the time of this IEFBR14 change,
> the OS initialized register 15 with 0 prior to invoking the called
> program, and a return value of 0 in register 15 meant "all is well"
> (like the Unix "true" command).
>
> However, an unrelated MVS change had now left register 15 in an
> unknown state before MVS invoked the called program, and (because
> IEFBR14 did not manipulate register 15 in any way), IEFBR14 now died
> ("abended" in IBM-speak) in random ways.
>
> So, the solution was to "fix" IEFBR14 so that it initialized
> register 15 to 0 before returning. This doubled the linecount from
> one instruction to two, and IEFBR14 became XR 15,15 BR 14
>
> So, even a program that "does nothing" can have bugs in it.
A couple of questions occur to me. What was the documented interface to
program startup? Did it specify that registers were in an “undefined”
state? Because otherwise it looks like you have one piece of IBM code
making assumptions about the internals of another piece of IBM code,
bypassing the public interfaces available to ordinary users.
And what does it mean, in a protected OS, to enter user code with
registers in an “undefined” state, anyway? Sounds like there is the
potential to leak confidential data to userland, whether from some
internal part of the OS or even from another user process. It seems
obvious that registers should always be initialized to a known state to
avoid such vulnerabilities.
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Re: VMS Rich <rich@example.invalid> - 2025-07-20 14:37 +0000
Re: VMS Richard Kettlewell <invalid@invalid.invalid> - 2025-07-21 08:42 +0100
Re: VMS John Ames <commodorejohn@gmail.com> - 2025-07-21 09:12 -0700
Re: VMS Pancho <Pancho.Jones@protonmail.com> - 2025-07-21 18:44 +0100
Re: VMS Richard Kettlewell <invalid@invalid.invalid> - 2025-07-21 20:47 +0100
Re: VMS John Ames <commodorejohn@gmail.com> - 2025-07-21 13:31 -0700
Re: VMS Pancho <Pancho.Jones@protonmail.com> - 2025-07-23 07:22 +0100
Re: VMS John Ames <commodorejohn@gmail.com> - 2025-07-23 08:04 -0700
Re: VMS John Ames <commodorejohn@gmail.com> - 2025-07-23 08:44 -0700
Re: VMS The Natural Philosopher <tnp@invalid.invalid> - 2025-07-23 20:04 +0100
Re: VMS rbowman <bowman@montana.com> - 2025-07-23 22:47 +0000
Re: VMS The Natural Philosopher <tnp@invalid.invalid> - 2025-07-24 09:56 +0100
Re: VMS Pancho <Pancho.Jones@protonmail.com> - 2025-07-23 21:53 +0100
Re: VMS John Ames <commodorejohn@gmail.com> - 2025-07-23 14:28 -0700
Re: VMS Pancho <Pancho.Jones@protonmail.com> - 2025-07-24 00:29 +0100
Re: VMS John Ames <commodorejohn@gmail.com> - 2025-07-24 08:05 -0700
Re: VMS Richard Kettlewell <invalid@invalid.invalid> - 2025-07-24 21:51 +0100
Re: VMS John Ames <commodorejohn@gmail.com> - 2025-07-24 15:06 -0700
Re: VMS Pancho <Pancho.Jones@protonmail.com> - 2025-07-25 07:06 +0100
Re: VMS John Ames <commodorejohn@gmail.com> - 2025-07-25 10:39 -0700
Re: VMS Pancho <Pancho.Jones@protonmail.com> - 2025-07-26 17:54 +0100
Re: VMS The Natural Philosopher <tnp@invalid.invalid> - 2025-07-26 18:02 +0100
Re: VMS Robert Riches <spamtrap42@jacob21819.net> - 2025-07-27 04:04 +0000
Re: VMS c186282 <c186282@nnada.net> - 2025-07-27 01:50 -0400
Re: VMS The Natural Philosopher <tnp@invalid.invalid> - 2025-07-27 12:07 +0100
Re: VMS Pancho <Pancho.Jones@protonmail.com> - 2025-07-27 10:23 +0100
Re: VMS Richard Kettlewell <invalid@invalid.invalid> - 2025-07-27 10:55 +0100
Re: VMS c186282 <c186282@nnada.net> - 2025-07-27 21:23 -0400
Re: VMS rbowman <bowman@montana.com> - 2025-07-28 04:45 +0000
Re: VMS c186282 <c186282@nnada.net> - 2025-07-28 02:14 -0400
Re: VMS The Natural Philosopher <tnp@invalid.invalid> - 2025-07-28 13:48 +0100
Re: VMS rbowman <bowman@montana.com> - 2025-07-28 20:38 +0000
Re: VMS rbowman <bowman@montana.com> - 2025-07-28 20:32 +0000
Re: VMS Bobbie Sellers <bliss-sf4ever@dslextreme.com> - 2025-07-28 14:17 -0700
Re: VMS rbowman <bowman@montana.com> - 2025-07-29 05:08 +0000
Re: VMS The Natural Philosopher <tnp@invalid.invalid> - 2025-07-28 13:44 +0100
Re: VMS The Natural Philosopher <tnp@invalid.invalid> - 2025-07-28 13:39 +0100
Re: VMS Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-07-29 01:03 +0000
Re: VMS rbowman <bowman@montana.com> - 2025-07-29 05:29 +0000
Re: VMS The Natural Philosopher <tnp@invalid.invalid> - 2025-07-29 11:42 +0100
Re: VMS rbowman <bowman@montana.com> - 2025-07-29 19:16 +0000
Re: VMS Pancho <Pancho.Jones@protonmail.com> - 2025-07-29 12:10 +0100
Re: VMS The Natural Philosopher <tnp@invalid.invalid> - 2025-07-29 13:08 +0100
Re: VMS Bobbie Sellers <bliss-sf4ever@dslextreme.com> - 2025-07-29 09:51 -0700
Re: VMS rbowman <bowman@montana.com> - 2025-07-29 18:53 +0000
Re: VMS c186282 <c186282@nnada.net> - 2025-07-29 04:51 -0400
Re: VMS Rich <rich@example.invalid> - 2025-07-29 13:32 +0000
Re: VMS John Ames <commodorejohn@gmail.com> - 2025-07-28 09:22 -0700
Re: VMS The Natural Philosopher <tnp@invalid.invalid> - 2025-07-27 12:11 +0100
Re: VMS Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-07-27 22:02 +0000
Re: VMS rbowman <bowman@montana.com> - 2025-07-28 04:58 +0000
Re: VMS Stéphane CARPENTIER <sc@fiat-linux.fr> - 2025-08-01 19:13 +0000
Re: VMS Lew Pitcher <lew.pitcher@digitalfreehold.ca> - 2025-08-01 20:38 +0000
Re: VMS Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-08-02 00:01 +0000
Re: VMS c186282 <c186282@nnada.net> - 2025-08-02 02:24 -0400
Re: VMS Pancho <Pancho.Jones@protonmail.com> - 2025-08-02 11:34 +0100
Re: VMS c186282 <c186282@nnada.net> - 2025-08-02 21:02 -0400
Re: VMS Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-08-03 02:08 +0000
Re: VMS c186282 <c186282@nnada.net> - 2025-08-03 01:00 -0400
Re: VMS Stéphane CARPENTIER <sc@fiat-linux.fr> - 2025-08-09 10:26 +0000
Re: VMS rbowman <bowman@montana.com> - 2025-08-09 20:00 +0000
Re: VMS Stéphane CARPENTIER <sc@fiat-linux.fr> - 2025-08-09 10:19 +0000
Re: VMS c186282 <c186282@nnada.net> - 2025-07-27 21:31 -0400
Re: VMS rbowman <bowman@montana.com> - 2025-07-28 05:03 +0000
Re: VMS c186282 <c186282@nnada.net> - 2025-07-28 02:19 -0400
Re: VMS c186282 <c186282@nnada.net> - 2025-07-27 21:09 -0400
Re: VMS John Ames <commodorejohn@gmail.com> - 2025-07-28 10:17 -0700
Re: VMS rbowman <bowman@montana.com> - 2025-07-28 20:46 +0000
Re: VMS John Ames <commodorejohn@gmail.com> - 2025-07-28 14:34 -0700
Re: VMS Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2025-07-28 16:34 +0000
Re: VMS rbowman <bowman@montana.com> - 2025-07-28 20:48 +0000
Re: VMS Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-07-29 01:00 +0000
Re: VMS Pancho <Pancho.Jones@protonmail.com> - 2025-07-29 10:07 +0100
Re: VMS Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-07-29 23:05 +0000
Re: VMS c186282 <c186282@nnada.net> - 2025-07-30 02:43 -0400
Re: VMS Andreas Eder <a_eder_muc@web.de> - 2025-08-02 18:11 +0200
Re: VMS Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2025-07-24 14:42 +0000
Re: VMS rbowman <bowman@montana.com> - 2025-07-24 18:05 +0000
Re: VMS John Ames <commodorejohn@gmail.com> - 2025-07-24 11:14 -0700
Re: VMS rbowman <bowman@montana.com> - 2025-07-24 23:10 +0000
Re: VMS Lawrence D'Oliveiro <ldo@nz.invalid> - 2025-07-24 21:16 +0000
Re: VMS rbowman <bowman@montana.com> - 2025-07-24 23:21 +0000
Re: VMS John Ames <commodorejohn@gmail.com> - 2025-07-21 14:05 -0700
Re: VMS Charlie Gibbs <cgibbs@kltpzyxm.invalid> - 2025-07-21 21:14 +0000
Re: VMS The Natural Philosopher <tnp@invalid.invalid> - 2025-07-21 22:19 +0100
Re: VMS rbowman <bowman@montana.com> - 2025-07-22 02:10 +0000
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