When /etc/mtab is a symlink of /proc/mounts, mke2fs can create a filesystem
on the loop mounted file without -F option. In this case, we should specify
-F option twice.
How to reproduce:
# mke2fs -t ext4 -Fq /mnt/mp1/fs.img
# mount -o loop /mnt/mp1/fs.img /mnt/mp2
# mke2fs -t ext4 -q /mnt/mp1/fs.img
/mnt/mp1/fs.img is not a block special device.
Proceed anyway? (y,n) y
# echo $?
0
Signed-off-by: Kazuya Mio <[email protected]>
---
configure.in | 2 ++
lib/ext2fs/ismounted.c | 38 ++++++++++++++++++++++++++++++++++++++
2 files changed, 40 insertions(+)
diff --git a/configure.in b/configure.in
index 8963d17..fe29aa3 100644
--- a/configure.in
+++ b/configure.in
@@ -912,6 +912,8 @@ AC_CHECK_HEADERS(m4_flatten([
linux/falloc.h
linux/fd.h
linux/major.h
+ linux/version.h
+ linux/loop.h
net/if_dl.h
netinet/in.h
sys/disklabel.h
diff --git a/lib/ext2fs/ismounted.c b/lib/ext2fs/ismounted.c
index 6a223df..499b4c0 100644
--- a/lib/ext2fs/ismounted.c
+++ b/lib/ext2fs/ismounted.c
@@ -21,6 +21,14 @@
#ifdef HAVE_LINUX_FD_H
#include <linux/fd.h>
#endif
+#ifdef HAVE_LINUX_VERSION_H
+#include <linux/version.h>
+#if LINUX_VERSION_CODE >= KERNEL_VERSION(2, 6, 0) /* kernel >= 2.6 */
+#ifdef HAVE_LINUX_LOOP_H
+#include <linux/loop.h>
+#endif /* HAVE_LINUX_LOOP_H */
+#endif /* kernel >= 2.6 */
+#endif /* HAVE_LINUX_VERSION_H */
#ifdef HAVE_MNTENT_H
#include <mntent.h>
#endif
@@ -31,6 +39,7 @@
#endif /* HAVE_GETMNTINFO */
#include <string.h>
#include <sys/stat.h>
+#include <sys/ioctl.h>
#include "ext2_fs.h"
#include "ext2fs.h"
@@ -51,6 +60,11 @@ static errcode_t check_mntent_file(const char *mtab_file, const char *file,
ino_t file_ino=0;
FILE *f;
int fd;
+#if defined(HAVE_LINUX_LOOP_H) && defined(LOOP_GET_STATUS64)
+ int result = 0;
+ struct loop_info64 lo_info;
+ memset(&lo_info, 0, sizeof(struct loop_info64));
+#endif /* defined(HAVE_LINUX_LOOP_H) && defined(LOOP_GET_STATUS64) */
*mount_flags = 0;
if ((f = setmntent (mtab_file, "r")) == NULL)
@@ -70,6 +84,30 @@ static errcode_t check_mntent_file(const char *mtab_file, const char *file,
continue;
if (strcmp(file, mnt->mnt_fsname) == 0)
break;
+#if defined(HAVE_LINUX_LOOP_H) && defined(LOOP_GET_STATUS64)
+ /*
+ * Check to see if a regular file is mounted.
+ * If /etc/mtab/ is a symlink of /proc/mounts, you will need
+ * the following check because the name in /proc/mounts
+ * is a loopback device not a regular file.
+ */
+ if (strncmp(mnt->mnt_fsname, "/dev/loop", 9) == 0) {
+ fd = open(mnt->mnt_fsname, O_RDONLY);
+ if (fd < 0) {
+ retval = errno;
+ goto errout;
+ }
+ result = ioctl(fd, LOOP_GET_STATUS64, &lo_info);
+ close(fd);
+ if (result < 0) {
+ retval = errno;
+ goto errout;
+ }
+ if (file_dev == lo_info.lo_device &&
+ file_ino == lo_info.lo_inode)
+ break;
+ }
+#endif /* defined(HAVE_LINUX_LOOP_H) && defined(LOOP_GET_STATUS64) */
if (stat(mnt->mnt_fsname, &st_buf) == 0) {
if (S_ISBLK(st_buf.st_mode)) {
#ifndef __GNU__