CVS commit: src/sys/kern

[Maxime Villard]

Module Name:    src
Committed By:   maxv
Date:           Thu Nov 29 10:27:36 UTC 2018

Modified Files:
        src/sys/kern: kern_sig.c

Log Message:
Fix kernel info leak, 4 bytes of padding at the end of struct sigaction.

        + Possible info leak: [len=32, leaked=4]
        | #0 0xffffffff80baf327 in kleak_copyout
        | #1 0xffffffff80bd9ca8 in sys___sigaction_sigtramp
        | #2 0xffffffff80259c42 in syscall


To generate a diff of this commit:
cvs rdiff -u -r1.349 -r1.350 src/sys/kern/kern_sig.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.


Modified files:

Index: src/sys/kern/kern_sig.c
diff -u src/sys/kern/kern_sig.c:1.349 src/sys/kern/kern_sig.c:1.350
--- src/sys/kern/kern_sig.c:1.349	Mon May 28 14:07:37 2018
+++ src/sys/kern/kern_sig.c	Thu Nov 29 10:27:36 2018
@@ -1,4 +1,4 @@
-/*	$NetBSD: kern_sig.c,v 1.349 2018/05/28 14:07:37 kamil Exp $	*/
+/*	$NetBSD: kern_sig.c,v 1.350 2018/11/29 10:27:36 maxv Exp $	*/
 
 /*-
  * Copyright (c) 2006, 2007, 2008 The NetBSD Foundation, Inc.
@@ -70,7 +70,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: kern_sig.c,v 1.349 2018/05/28 14:07:37 kamil Exp $");
+__KERNEL_RCSID(0, "$NetBSD: kern_sig.c,v 1.350 2018/11/29 10:27:36 maxv Exp $");
 
 #include "opt_ptrace.h"
 #include "opt_dtrace.h"
@@ -190,6 +190,13 @@ signal_listener_cb(kauth_cred_t cred, ka
 	return result;
 }
 
+static int
+sigacts_ctor(void *arg __unused, void *obj, int flags __unused)
+{
+	memset(obj, 0, sizeof(struct sigacts));
+	return 0;
+}
+
 /*
  * signal_init:
  *
@@ -203,7 +210,7 @@ signal_init(void)
 
 	sigacts_cache = pool_cache_init(sizeof(struct sigacts), 0, 0, 0,
 	    "sigacts", sizeof(struct sigacts) > PAGE_SIZE ?
-	    &sigactspool_allocator : NULL, IPL_NONE, NULL, NULL, NULL);
+	    &sigactspool_allocator : NULL, IPL_NONE, sigacts_ctor, NULL, NULL);
 	ksiginfo_cache = pool_cache_init(sizeof(ksiginfo_t), 0, 0, 0,
 	    "ksiginfo", NULL, IPL_VM, NULL, NULL, NULL);