Commit 0adab2b6 authored by Thomas Weißschuh's avatar Thomas Weißschuh
Browse files

tools/nolibc: add support for uname(2) 

All supported kernels are assumed to use struct new_utsname.
This is validated in test_uname().

uname(2) can for example be used in ksft_min_kernel_version() from the
kernels selftest framework.

Link: https://lore.kernel.org/lkml/20240412123536.GA32444@redhat.com/


Signed-off-by: default avatarThomas Weißschuh <linux@weissschuh.net>
Acked-by: default avatarWilly Tarreau <w@1wt.eu>
parent e93b912e

tools/include/nolibc/sys.h

+27 −0
Original line number Diff line number Diff line
@@ -22,6 +22,7 @@ 
#include <linux/stat.h>  /* for statx() */

#include <linux/prctl.h>

#include <linux/resource.h>

#include <linux/utsname.h>



#include "arch.h"

#include "errno.h"
@@ -1139,6 +1140,32 @@ int umount2(const char *path, int flags) 
}





/*

 * int uname(struct utsname *buf);

 */



struct utsname {

	char sysname[65];

	char nodename[65];

	char release[65];

	char version[65];

	char machine[65];

	char domainname[65];

};



static __attribute__((unused))

int sys_uname(struct utsname *buf)

{

	return my_syscall1(__NR_uname, buf);

}



static __attribute__((unused))

int uname(struct utsname *buf)

{

	return __sysret(sys_uname(buf));

}





/*

 * int unlink(const char *path);

 */

tools/testing/selftests/nolibc/nolibc-test.c

+42 −0
Original line number Diff line number Diff line
@@ -27,6 +27,7 @@ 
#include <sys/syscall.h>

#include <sys/sysmacros.h>

#include <sys/time.h>

#include <sys/utsname.h>

#include <sys/wait.h>

#include <dirent.h>

#include <errno.h>
@@ -780,6 +781,45 @@ int test_stat_timestamps(void) 
	return 0;

}



int test_uname(void)

{

	struct utsname buf;

	char osrelease[sizeof(buf.release)];

	ssize_t r;

	int fd;



	memset(&buf.domainname, 'P', sizeof(buf.domainname));



	if (uname(&buf))

		return 1;



	if (strncmp("Linux", buf.sysname, sizeof(buf.sysname)))

		return 1;



	fd = open("/proc/sys/kernel/osrelease", O_RDONLY);

	if (fd == -1)

		return 1;



	r = read(fd, osrelease, sizeof(osrelease));

	if (r == -1)

		return 1;



	close(fd);



	if (osrelease[r - 1] == '\n')

		r--;



	/* Validate one of the later fields to ensure field sizes are correct */

	if (strncmp(osrelease, buf.release, r))

		return 1;



	/* Ensure the field domainname is set, it is missing from struct old_utsname */

	if (strnlen(buf.domainname, sizeof(buf.domainname)) == sizeof(buf.domainname))

		return 1;



	return 0;

}



int test_mmap_munmap(void)

{

	int ret, fd, i, page_size;
@@ -985,6 +1025,8 @@ int run_syscall(int min, int max) 
		CASE_TEST(stat_fault);        EXPECT_SYSER(1, stat(NULL, &stat_buf), -1, EFAULT); break;

		CASE_TEST(stat_timestamps);   EXPECT_SYSZR(1, test_stat_timestamps()); break;

		CASE_TEST(symlink_root);      EXPECT_SYSER(1, symlink("/", "/"), -1, EEXIST); break;

		CASE_TEST(uname);             EXPECT_SYSZR(proc, test_uname()); break;

		CASE_TEST(uname_fault);       EXPECT_SYSER(1, uname(NULL), -1, EFAULT); break;

		CASE_TEST(unlink_root);       EXPECT_SYSER(1, unlink("/"), -1, EISDIR); break;

		CASE_TEST(unlink_blah);       EXPECT_SYSER(1, unlink("/proc/self/blah"), -1, ENOENT); break;

		CASE_TEST(wait_child);        EXPECT_SYSER(1, wait(&tmp), -1, ECHILD); break;