Rework the support for ABIs to override resource limits (used by 32-bit

processes under 64-bit kernels).  Previously, each 32-bit process overwrote
its resource limits at exec() time.  The problem with this approach is that
the new limits affect all child processes of the 32-bit process, including
if the child process forks and execs a 64-bit process.  To fix this, don't
ovewrite the resource limits during exec().  Instead, sv_fixlimits() is
now replaced with a different function sv_fixlimit() which asks the ABI to
sanitize a single resource limit.  We then use this when querying and
setting resource limits.  Thus, if a 32-bit process sets a limit, then
that new limit will be inherited by future children.  However, if the
32-bit process doesn't change a limit, then a future 64-bit child will
see the "full" 64-bit limit rather than the 32-bit limit.

MFC is tentative since it will break the ABI of old linux.ko modules (no
other modules are affected).

MFC after:	1 week

1 files changed, 2 insertions, 2 deletions

diff --git a/sys/sys/sysent.h b/sys/sys/sysent.h
index edf1717..ba8fc4b 100644
--- a/sys/sys/sysent.h
+++ b/sys/sys/sysent.h
@@ -34,7 +34,7 @@
 
 #include <bsm/audit.h>
 
-struct proc;
+struct rlimit;
 struct sysent;
 struct thread;
 struct ksiginfo;
@@ -98,7 +98,7 @@ struct sysentvec {
 	int		sv_stackprot;	/* vm protection for stack */
 	register_t	*(*sv_copyout_strings)(struct image_params *);
 	void		(*sv_setregs)(struct thread *, u_long, u_long, u_long);
-	void		(*sv_fixlimits)(struct proc *);
+	void		(*sv_fixlimit)(struct rlimit *, int);
 };
 
 #ifdef _KERNEL