From: deraadt <deraadt@openbsd.org>
Date: Mon, 10 Jul 2023 22:54:40 +0000 (+0000)
Subject: Allow unveiled programs to dump core (in the default, classic, into . way)
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=8447828fb0903987bef7a6c07a95b4bcfafa9315;p=openbsd

Allow unveiled programs to dump core (in the default, classic, into . way)
by passing BYPASSUNVEIL just for this vnode.  The coredump() code is quite
careful, so this will be fine.
ok kn kettenis semarie
---

diff --git a/sys/kern/kern_sig.c b/sys/kern/kern_sig.c
index 5304c904dab..98683fe16ff 100644
--- a/sys/kern/kern_sig.c
+++ b/sys/kern/kern_sig.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_sig.c,v 1.307 2023/06/28 08:23:25 claudio Exp $	*/
+/*	$OpenBSD: kern_sig.c,v 1.308 2023/07/10 22:54:40 deraadt Exp $	*/
 /*	$NetBSD: kern_sig.c,v 1.54 1996/04/22 01:38:32 christos Exp $	*/
 
 /*
@@ -1699,7 +1699,7 @@ coredump(struct proc *p)
 	}
 
 	/* incrash should be 0 or KERNELPATH only */
-	NDINIT(&nd, 0, incrash, UIO_SYSSPACE, name, p);
+	NDINIT(&nd, 0, BYPASSUNVEIL | incrash, UIO_SYSSPACE, name, p);
 
 	error = vn_open(&nd, O_CREAT | FWRITE | O_NOFOLLOW | O_NONBLOCK,
 	    S_IRUSR | S_IWUSR);
diff --git a/sys/kern/vfs_vnops.c b/sys/kern/vfs_vnops.c
index e6a175e9f16..765b70a0947 100644
--- a/sys/kern/vfs_vnops.c
+++ b/sys/kern/vfs_vnops.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vfs_vnops.c,v 1.121 2022/08/14 01:58:28 jsg Exp $	*/
+/*	$OpenBSD: vfs_vnops.c,v 1.122 2023/07/10 22:54:40 deraadt Exp $	*/
 /*	$NetBSD: vfs_vnops.c,v 1.20 1996/02/04 02:18:41 christos Exp $	*/
 
 /*
@@ -86,13 +86,13 @@ vn_open(struct nameidata *ndp, int fmode, int cmode)
 	int error;
 
 	/*
-	 * The only valid flag to pass in here from NDINIT is
-	 * KERNELPATH, This function will override the nameiop based
-	 * on the fmode and cmode flags, So validate that our caller
-	 * has not set other flags or operations in the nameidata
+	 * The only valid flags to pass in here from NDINIT are
+	 * KERNELPATH or BYPASSUNVEIL. This function will override the
+	 * nameiop based on the fmode and cmode flags, so validate that
+	 * our caller has not set other flags or operations in the nameidata
 	 * structure.
 	 */
-	KASSERT(ndp->ni_cnd.cn_flags == 0 || ndp->ni_cnd.cn_flags == KERNELPATH);
+	KASSERT((ndp->ni_cnd.cn_flags & ~(KERNELPATH|BYPASSUNVEIL)) == 0);
 	KASSERT(ndp->ni_cnd.cn_nameiop == 0);
 
         if ((fmode & (FREAD|FWRITE)) == 0)