From 6df1b2474adfc23c9cfff5a4496108bea0c37511 Mon Sep 17 00:00:00 2001 From: Roland McGrath Date: Thu, 4 Jan 1996 00:06:01 +0000 Subject: Rewritten. --- sysdeps/mach/hurd/fork.c | 22 ++++++++++++++++++++-- sysdeps/mach/hurd/jmp-unwind.c | 6 +++--- sysdeps/mach/hurd/setgid.c | 27 ++++++++++++--------------- 3 files changed, 35 insertions(+), 20 deletions(-) (limited to 'sysdeps/mach/hurd') diff --git a/sysdeps/mach/hurd/fork.c b/sysdeps/mach/hurd/fork.c index 25279645ee..6fadb3d97d 100644 --- a/sysdeps/mach/hurd/fork.c +++ b/sysdeps/mach/hurd/fork.c @@ -1,4 +1,4 @@ -/* Copyright (C) 1994, 1995 Free Software Foundation, Inc. +/* Copyright (C) 1994, 1995, 1996 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or @@ -121,7 +121,6 @@ __fork (void) __spin_lock (&_hurd_ports[i].lock); ports_locked = 1; - *(volatile task_t *) &__mach_task_self_; /* XXX work around kernel bug */ /* Stop all other threads while copying the address space, so nothing changes. */ @@ -130,6 +129,25 @@ __fork (void) { stopped = 1; +#define XXX_KERNEL_PAGE_FAULT_BUG /* XXX work around page fault bug in mk */ + +#ifdef XXX_KERNEL_PAGE_FAULT_BUG + /* Gag me with a pitchfork. + The bug scenario is this: + + - The page containing __mach_task_self_ is paged out. + - The signal thread was faulting on that page when we + suspended it via proc_dostop. It holds some lock, or set + some busy bit, or somesuch. + - Now this thread faults on that same page. + - GRATUIOUS DEADLOCK + + We can break the deadlock by aborting the thread that faulted + first, which if the bug happened was the signal thread because + it is the only other thread and we just suspended it. + */ + __thread_abort (_hurd_msgport_thread); +#endif /* Create the child task. It will inherit a copy of our memory. */ err = __task_create (__mach_task_self (), 1, &newtask); } diff --git a/sysdeps/mach/hurd/jmp-unwind.c b/sysdeps/mach/hurd/jmp-unwind.c index 822501f8e5..20ca5f8aa6 100644 --- a/sysdeps/mach/hurd/jmp-unwind.c +++ b/sysdeps/mach/hurd/jmp-unwind.c @@ -1,5 +1,5 @@ /* _longjmp_unwind -- Clean up stack frames unwound by longjmp. Hurd version. -Copyright (C) 1995 Free Software Foundation, Inc. +Copyright (C) 1995, 1996 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or @@ -18,8 +18,9 @@ not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ #include -#include #include +#include +#include #include @@ -36,7 +37,6 @@ _longjmp_unwind (jmp_buf env, int val) { struct hurd_sigstate *ss = _hurd_self_sigstate (); struct hurd_userlink *link; - struct hurd_signal_preempter **p; /* All access to SS->active_resources must take place inside a critical section where signal handlers cannot run. */ diff --git a/sysdeps/mach/hurd/setgid.c b/sysdeps/mach/hurd/setgid.c index b2d9313307..ca493a4f7b 100644 --- a/sysdeps/mach/hurd/setgid.c +++ b/sysdeps/mach/hurd/setgid.c @@ -1,4 +1,4 @@ -/* Copyright (C) 1991, 1992, 1993, 1994, 1995 Free Software Foundation, Inc. +/* Copyright (C) 1991, 92, 93, 94, 95, 96 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or @@ -46,21 +46,26 @@ DEFUN(__setgid, (gid), gid_t gid) gid_t *newgen, *newaux, auxbuf[2]; size_t ngen, naux; - newaux = _hurd_id.aux.gids; - naux = _hurd_id.aux.ngids; if (_hurd_id.gen.ngids == 0) { /* No effective gids now. The new set will be just GID. */ newgen = &gid; ngen = 1; } - else if (_hurd_id.gen.gids[0] == 0) + else { - /* We are root; set the effective, real, and saved to GID. */ _hurd_id.gen.gids[0] = gid; _hurd_id.valid = 0; newgen = _hurd_id.gen.gids; ngen = _hurd_id.gen.ngids; + } + + newaux = _hurd_id.aux.gids; + naux = _hurd_id.aux.ngids; + if (_hurd_id.gen.nuids > 0 && _hurd_id.gen.uids[0] == 0) + { + /* We are root; set the real and saved IDs too. */ + _hurd_id.valid = 0; if (_hurd_id.aux.ngids < 2) { newaux = auxbuf; @@ -68,20 +73,12 @@ DEFUN(__setgid, (gid), gid_t gid) } newaux[0] = newaux[1] = gid; } - else - { - /* We are not root; just change the effective GID. */ - _hurd_id.gen.gids[0] = gid; - _hurd_id.valid = 0; - newgen = _hurd_id.gen.gids; - ngen = _hurd_id.gen.ngids; - } err = __USEPORT (AUTH, __auth_makeauth (port, NULL, MACH_MSG_TYPE_COPY_SEND, 0, + _hurd_id.gen.uids, _hurd_id.gen.nuids, + _hurd_id.aux.uids, _hurd_id.aux.nuids, newgen, ngen, newaux, naux, - _hurd_id.gen.gids, _hurd_id.gen.ngids, - _hurd_id.aux.gids, _hurd_id.aux.ngids, &newauth)); } __mutex_unlock (&_hurd_id.lock); -- cgit 1.4.1