Fix corner cases of getgroups and setgroups syscall decoders

* uid.c (print_groups): New function.
(SYS_FUNC(setgroups), SYS_FUNC(getgroups)): Use it.
Print first syscall argument using %u format.
* tests/getgroups.c: New file.
* tests/getgroups.test: New test.
* tests/getgroups32.c: New file.
* tests/getgroups32.test: New test.
* tests/setgroups.c: New file.
* tests/setgroups.test: New test.
* tests/setgroups32.c: New file.
* tests/setgroups32.test: New test.
* tests/.gitignore: Add getgroups, getgroups32, setgroups,
and setgroups32.
* tests/Makefile.am (check_PROGRAMS): Likewise.
(DECODER_TESTS): Add getgroups.test, getgroups32.test,
setgroups.test, and setgroups32.test.

1 files changed, 161 insertions, 0 deletions

diff --git a/tests/getgroups.c b/tests/getgroups.c
new file mode 100644
index 000000000..e853b25c5
--- /dev/null
+++ b/tests/getgroups.c
@@ -0,0 +1,161 @@
+/*
+ * Check decoding of getgroups/getgroups32 syscalls.
+ *
+ * Copyright (c) 2016 Dmitry V. Levin <ldv@altlinux.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifdef __NR_getgroups32
+
+# define SYSCALL_NR	__NR_getgroups32
+# define SYSCALL_NAME	"getgroups32"
+# define GID_TYPE	unsigned int
+
+#else
+
+# include "tests.h"
+# include <sys/syscall.h>
+
+# ifdef __NR_getgroups
+
+#  define SYSCALL_NR	__NR_getgroups
+#  define SYSCALL_NAME	"getgroups"
+#  if defined __NR_getgroups32 && __NR_getgroups != __NR_getgroups32
+#   define GID_TYPE	unsigned short
+#  else
+#   define GID_TYPE	unsigned int
+#  endif
+
+# endif
+
+#endif
+
+#ifdef GID_TYPE
+
+# include <errno.h>
+# include <stdio.h>
+# include <unistd.h>
+
+static const char *
+errno2str(void)
+{
+	switch (errno) {
+#define CASE(x) case x: return #x
+		CASE(EINVAL);
+		CASE(EFAULT);
+		default: perror_msg_and_fail(SYSCALL_NAME);
+	}
+}
+
+#define MAX_STRLEN 32
+static long ngroups;
+
+static void
+get_groups(const long size, GID_TYPE *const g)
+{
+	long i = syscall(SYSCALL_NR, size, g);
+	if (i != ngroups)
+		perror_msg_and_fail("%s(%#lx, %p)", SYSCALL_NAME, size, g);
+
+	printf("%s(%u, [", SYSCALL_NAME, (unsigned) size);
+	for (i = 0; i < ngroups; ++i) {
+		if (i)
+			printf(", ");
+		if (i >= MAX_STRLEN) {
+			printf("...");
+			break;
+		}
+		printf("%u", (unsigned int) g[i]);
+	}
+	printf("]) = %ld\n", ngroups);
+}
+
+int
+main(void)
+{
+	long rc;
+
+	/* check how the first argument is decoded */
+	ngroups = syscall(SYSCALL_NR, 0, 0);
+	printf("%s(0, NULL) = %ld\n", SYSCALL_NAME, ngroups);
+	if (ngroups < 0)
+		perror_msg_and_fail(SYSCALL_NAME);
+
+	rc = syscall(SYSCALL_NR, (long) 0xffffffff00000000ULL, 0);
+	printf("%s(0, NULL) = %ld\n", SYSCALL_NAME, rc);
+
+	rc = syscall(SYSCALL_NR, -1U, 0);
+	printf("%s(%u, NULL) = %ld %s (%m)\n",
+	       SYSCALL_NAME, -1U, rc, errno2str());
+
+	rc = syscall(SYSCALL_NR, -1L, 0);
+	printf("%s(%u, NULL) = %ld %s (%m)\n",
+	       SYSCALL_NAME, -1U, rc, errno2str());
+
+	const unsigned int ngroups_max = sysconf(_SC_NGROUPS_MAX);
+
+	rc = syscall(SYSCALL_NR, ngroups_max, 0);
+	if (rc < 0)
+		printf("%s(%u, NULL) = %ld %s (%m)\n",
+		       SYSCALL_NAME, ngroups_max, rc, errno2str());
+	else
+		printf("%s(%u, NULL) = %ld\n",
+		       SYSCALL_NAME, ngroups_max, rc);
+
+	rc = syscall(SYSCALL_NR, (long) 0xffffffff00000000ULL | ngroups_max, 0);
+	if (rc < 0)
+		printf("%s(%u, NULL) = %ld %s (%m)\n",
+		       SYSCALL_NAME, ngroups_max, rc, errno2str());
+	else
+		printf("%s(%u, NULL) = %ld\n",
+		       SYSCALL_NAME, ngroups_max, rc);
+
+	/* check how the second argument is decoded */
+	GID_TYPE *const g1 =
+		tail_alloc(ngroups ? sizeof(*g1) * ngroups : 1);
+	GID_TYPE *const g2 = tail_alloc(sizeof(*g2) * (ngroups + 1));
+	void *efault = g2 + ngroups + 1;
+	(void) tail_alloc(1);
+
+	get_groups(ngroups, g1);
+	get_groups(ngroups + 1, g1);
+	get_groups(ngroups + 1, g2);
+
+	if (ngroups) {
+		rc = syscall(SYSCALL_NR, ngroups, efault);
+		printf("%s(%u, %p) = %ld %s (%m)\n",
+		       SYSCALL_NAME, (unsigned) ngroups, efault,
+		       rc, errno2str());
+	}
+
+	puts("+++ exited with 0 +++");
+	return 0;
+}
+
+#else
+
+SKIP_MAIN_UNDEFINED("__NR_getgroups")
+
+#endif