Commit a3322868 authored by Alexey Dobriyan's avatar Alexey Dobriyan Committed by Linus Torvalds

tmpfs: test link accounting with O_TMPFILE

Mount tmpfs with "nr_inodes=3" for easy check.

Link: http://lkml.kernel.org/r/20190219215016.GA20084@avx2Signed-off-by: default avatarAlexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Cc: Darrick J. Wong <darrick.wong@oracle.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matej Kupljen <matej.kupljen@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 2367fab5
...@@ -48,6 +48,7 @@ TARGETS += sysctl ...@@ -48,6 +48,7 @@ TARGETS += sysctl
ifneq (1, $(quicktest)) ifneq (1, $(quicktest))
TARGETS += timers TARGETS += timers
endif endif
TARGETS += tmpfs
TARGETS += user TARGETS += user
TARGETS += vm TARGETS += vm
TARGETS += x86 TARGETS += x86
......
CFLAGS += -Wall -O2
CFLAGS += -D_GNU_SOURCE
TEST_GEN_PROGS :=
TEST_GEN_PROGS += bug-link-o-tmpfile
include ../lib.mk
/*
* Copyright (c) 2019 Alexey Dobriyan <adobriyan@gmail.com>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/* Test that open(O_TMPFILE), linkat() doesn't screw accounting. */
#include <errno.h>
#include <sched.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/mount.h>
#include <unistd.h>
int main(void)
{
int fd;
if (unshare(CLONE_NEWNS) == -1) {
if (errno == ENOSYS || errno == EPERM) {
fprintf(stderr, "error: unshare, errno %d\n", errno);
return 4;
}
fprintf(stderr, "error: unshare, errno %d\n", errno);
return 1;
}
if (mount(NULL, "/", NULL, MS_PRIVATE|MS_REC, NULL) == -1) {
fprintf(stderr, "error: mount '/', errno %d\n", errno);
return 1;
}
/* Our heroes: 1 root inode, 1 O_TMPFILE inode, 1 permanent inode. */
if (mount(NULL, "/tmp", "tmpfs", 0, "nr_inodes=3") == -1) {
fprintf(stderr, "error: mount tmpfs, errno %d\n", errno);
return 1;
}
fd = openat(AT_FDCWD, "/tmp", O_WRONLY|O_TMPFILE, 0600);
if (fd == -1) {
fprintf(stderr, "error: open 1, errno %d\n", errno);
return 1;
}
if (linkat(fd, "", AT_FDCWD, "/tmp/1", AT_EMPTY_PATH) == -1) {
fprintf(stderr, "error: linkat, errno %d\n", errno);
return 1;
}
close(fd);
fd = openat(AT_FDCWD, "/tmp", O_WRONLY|O_TMPFILE, 0600);
if (fd == -1) {
fprintf(stderr, "error: open 2, errno %d\n", errno);
return 1;
}
return 0;
}
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