[apparmor] [patch] tests: readdir - test both getdents() and getdents64() if available

[Steve Beattie]

Hey Colin,

On Tue, Apr 04, 2017 at 03:16:29PM -0000, Colin Ian King wrote:
> Colin Ian King has proposed merging lp:~colin-king/apparmor/fix-arm64-test-builds into lp:apparmor.
> 
> Requested reviews:
>   AppArmor Developers (apparmor-dev)
> 
> For more details, see:
> https://code.launchpad.net/~colin-king/apparmor/fix-arm64-test-builds/+merge/321876
> 
> This fixes build issues for the readdir test for arm64 where getdents(2)
> is not wired up as a system call but gendents64(2) is available.
> This changes the preference to use the 64 bit system call by default
> if it is available on 64 bit systems.

Thanks for providing this fix.

Realastically, though, where an architecture supports both getdents()
and getdents64(), we ought to be ensuring that apparmor mediation occurs
on both syscall paths. What follows is a patch that attempts to do that.

Subject: tests: readdir - test both getdents() and getdents64() if available

In commit 3649, Colin King fixed the readdir test build issue where aarch64 only
supports getdetns64(), not getdents(). Realistically, however, we want
to ensure mediation occurs on both syscalls where they exist. This patch
changes the test to attempt performing both versions of getdents().

Bug: https://bugs.launchpad.net/bugs/1674245

Signed-off-by: Steve Beattie <steve at nxnw.org>
---
 tests/regression/apparmor/readdir.c |   80 ++++++++++++++++++++++++++----------
 1 file changed, 59 insertions(+), 21 deletions(-)

Index: b/tests/regression/apparmor/readdir.c
===================================================================
--- a/tests/regression/apparmor/readdir.c
+++ b/tests/regression/apparmor/readdir.c
@@ -1,10 +1,14 @@
 /*
  *	Copyright (C) 2002-2006 Novell/SUSE
+ *	Copyright (C) 2017 Canonical, Ltd.
  *
  *	This program is free software; you can redistribute it and/or
  *	modify it under the terms of the GNU General Public License as
  *	published by the Free Software Foundation, version 2 of the
  *	License.
+ *
+ *	We attempt to test both getdents() and getdents64() here, but
+ *	some architectures like aarch64 only support getdents64().
  */
 #define _GNU_SOURCE
 
@@ -18,45 +22,79 @@
 #include <string.h>
 #include <sys/syscall.h>
 
-int main(int argc, char *argv[])
+#ifdef SYS_getdents
+int my_readdir(char *dirname)
 {
 	int fd;
-#if defined(SYS_getdents64)
-	struct dirent64 dir;
-#else
 	struct dirent dir;
-#endif
 
-	if (argc != 2){
-		fprintf(stderr, "usage: %s dir\n",
-			argv[0]);
+	fd = open(dirname, O_RDONLY, 0);
+	if (fd == -1) {
+		printf("FAIL - open  %s\n", strerror(errno));
 		return 1;
 	}
 
-	fd = open(argv[1], O_RDONLY, 0);
-	if (fd == -1){
-		printf("FAIL - open  %s\n", strerror(errno));
+	/* getdents isn't exported by glibc, so must use syscall() */
+	if (syscall(SYS_getdents, fd, &dir, sizeof(dir)) == -1){
+		printf("FAIL - getdents  %s\n", strerror(errno));
+		close(fd);
 		return 1;
 	}
 
-	/*
-	if (fchdir(fd) == -1){
-		printf("FAIL - fchdir  %s\n", strerror(errno));
+	close(fd);
+	return 0;
+}
+#else
+int my_readdir(char *dirname) { return 0; }
+#endif
+
+#ifdef SYS_getdents64
+int my_readdir64(char *dirname)
+{
+	int fd;
+	struct dirent64 dir;
+
+	fd = open(dirname, O_RDONLY, 0);
+	if (fd == -1) {
+		printf("FAIL - open  %s\n", strerror(errno));
 		return 1;
 	}
-	*/
 
 	/* getdents isn't exported by glibc, so must use syscall() */
-#if defined(SYS_getdents64)
-	if (syscall(SYS_getdents64, fd, &dir, sizeof(struct dirent64)) == -1){
+	if (syscall(SYS_getdents64, fd, &dir, sizeof(dir)) == -1){
+		printf("FAIL - getdents64  %s\n", strerror(errno));
+		close(fd);
+		return 1;
+	}
+
+	close(fd);
+	return 0;
+}
 #else
-	if (syscall(SYS_getdents, fd, &dir, sizeof(struct dirent)) == -1){
+int my_readdir64(char *dirname) { return 0; }
 #endif
-		printf("FAIL - getdents  %s\n", strerror(errno));
-		return 1;
+
+int main(int argc, char *argv[])
+{
+	int rc = 0;
+
+	if (argc != 2) {
+		fprintf(stderr, "usage: %s dir\n",
+			argv[0]);
+		rc = 1;
+		goto err;
 	}
 
+	rc = my_readdir(argv[1]);
+	if (rc != 0)
+		goto err;
+
+	rc = my_readdir64(argv[1]);
+	if (rc != 0)
+		goto err;
+
 	printf("PASS\n");
 
-	return 0;
+err:
+	return rc;
 }


-- 
Steve Beattie
<sbeattie at ubuntu.com>
http://NxNW.org/~steve/
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 819 bytes
Desc: not available
URL: <https://lists.ubuntu.com/archives/apparmor/attachments/20170404/d96aa3c4/attachment.pgp>